Abstract Book - International Symposium on Molecular Spectroscopy
Transcription
Abstract Book - International Symposium on Molecular Spectroscopy
Welcome to the 64th OSU International Symposium on Molecular Spectroscopy On behalf of the Executive Committee, Frank DeLucia, Eric Herbst, Anne B. McCoy, and myself, I extend to all our Symposium guests a heartfelt welcome to the 64th Symposium and more broadly to The Ohio State University and Columbus. The Symposium presents recent work in molecular spectroscopy and related fields. The number of talks, their variety, and the fact that many are given by students, all indicate the continued vitality and significance of our field. The presentations, which are documented in this Abstract Book, are the heart of the meeting. However information at the Symposium also flows from informal exchanges and discussions as well as the talks. As organizers, we strive to provide an environment that facilitates both kinds of interactions. The essence of the meeting lies in the scientific discussions and your personal experiences this week, independent of the number of times that you have attended this meeting. It is our sincere hope that you will find this meeting informative and enjoyable both scientifically and personally. If we can help to enhance your experience, please do not hesitate to ask the Symposium staff or the Executive Committee. Terry A. Miller Symposium Chair Contents SCHEDULE OF TALKS ABSTRACTS Monday (M)....................1 Monday (M)...................86 Tuesday (T)...................15 Tuesday (T)..................119 Wednesday (W).............40 Wednesday (W)............180 Thursday (R).................54 Thursday (R)................215 Friday (F).....................78 Friday (F).....................274 AUTHOR INDEX..................293 ACKNOWLEDGMENTS......301 64th OSU INTERNATIONAL SYMPOSIUM ON MOLECULAR SPECTROSCOPY JUNE 22-26, 2009 International Advisory Committee David Anderson, U. Wyoming Alain Barbe, U. Reims Walther Caminati, U. Bologna Fleming Crim*, U. Wisconsin Kentarou Kawaguchi, Okayama U. Zbigniew Kisiel, PAN (Poland) Yuan-Pern Lee, National Chiao Tung U. Carl Lineberger, JILA/U. Colorado *steering committee member e-mail: mss@molspect.chemistry.ohio-state.edu Executive Committee Terry A. Miller, Chair Frank C. DeLucia, Eric Herbst Anne B. McCoy Please send correspondence to: Terry A. Miller International Symposium on Molecular Spectroscopy Department of Chemistry 100 West 18th Avenue Columbus, Ohio 43210 USA International Advisory Committee Mark Marshall*, Amherst College Ben McCall, U. Illinois Frederic Merkt, ETH Zurich Andrew Orr-Ewing, U. Bristol Scott Reid*, Marquette U. David Dale Skatrud, ARO Li-Hong Xu*, U. New Brunswick Lucy Ziurys, U. Arizona, Chair* *steering committee member 614-292-2569 (phone),-1948 (FAX) http://molspect.chemistry.ohio-state.edu/symposium/ Special Sessions For the 64th Symposium, Li-Hong Xu, University of New Brunswick, and John Pearson, JPL/NASA, are organizing a mini-symposium entitled, “FIR/THz Air/Space Missions” covering spectroscopic needs relevant to current and emerging atmospheric and space missions, including Herschel, ALMA, SOFIA, SPIRIT, and JWST. This mini-symposium is designed to bring together researchers working on a host of different systems ranging from techniques to complex molecules. Contributions are encouraged from across the full range of molecular systems and for atmospheric, astronomical, and spectroscopic techniques from the microwave to the far infrared. Invited speakers will include Frank C. De Lucia, The Ohio State University; Robert McKellar, Steacie Institute for Molecular Sciences, National Research Council of Canada; Karl Menten, Max-Planck Institut fur Radioastronomie, Bonn; and Holger S. P. Müller, Universität zü Köln. A second mini-symposium is being organized by Scott Reid, Marquette University, and Spiridoula Matsika, Temple University, on the subject of Conical Intersections. This mini-symposium is designed to bring together theoretical and experimental researchers with common interests in exploring the involvement of conical intersections in the spectroscopy and dynamics of molecular systems. Theoretical and experimental contributions in methodological developments and applications have been encouraged. Invited talks for this mini-symposium will be given by David Jonas, Colorado University, and Todd Martinez, Stanford University. A third mini-symposium is being organized by Andrew Orr-Ewing, University of Bristol, and Kevin Lehmann, University of Virginia, entitled “Developments in Cavity Enhanced Spectroscopy.” This mini-symposium will review advances in cavity enhanced spectroscopic techniques such as CRDS, CEAS and NICEOHMS, and their wide-ranging applications in fields that include fundamental molecular spectroscopy, atmospheric and combustion chemistry. Invited speakers include Andreas Brockhinke, Universität Bielefeld; Steven S. Brown, NOAA Earth System Research Lab; and Jun Ye, NIST/University of Colorado. A session on theory is being organized by Anne McCoy, John Herbert, and Russell Pitzer, Ohio State University, featuring an invited talk by Jon Hougen, NIST. Picnic The Symposium picnic will be held on Wednesday evening, June 24, at the Fawcett Center. The cost of the picnic is included in your registration (at below cost to students), so that all may attend the event. The Coblentz Society is the host for refreshments at 6:30pm before the picnic which is scheduled to commence at 7:30pm at the Fawcett Center. Sponsorship We are pleased to announce our anticipated sponsorship for the 64th Symposium. The principal funding will come from the Army Office of Research (ARO). We are most grateful to ARO for their continued support. Our Corporate sponsors are Elsevier, which supports the Journal of Molecular Spectroscopy Special Lecture, Coherent, which subsidizes the cost of the Picnic for students, Quantel, which supports the Women’s Lunch, and Virginia Diodes which subsidizes the cost of the Coffee. We are pleased to acknowledge Bristol Instruments, Bruker Optics, CyberWit, Lockheed Martin Aculight Corporation, Newport/SpectraPhysics, Princeton Instruments and Qioptiq/LINOS Photonics, as Contributing sponsors. IOS Press has a special insert in all Conferee packets. Our sponsors will have exhibits at the Symposium and we encourage you to visit their displays. Rao Prize The three Rao Prizes for the most outstanding student talks at the 2008 meeting will be presented. The winners are Frank Filsinger, Max-Planck-Gesellschaft; Jen Nicole Landry, University of Alberta; and Fumie Xe Sunahori, University of Kentucky. The Rao Prize was created by a group of spectroscopists who, as graduate students, benefited from the emphasis on graduate student participation, which has been a unique characteristic of the Symposium. This year three more Rao Prizes will be awarded. The award is administered by a Prize Committee chaired by Brenda Winnewisser, Ohio State University and comprised of Kevin Lehmann, University of Virginia; John Muenter, University of Rochester; Brooks Pate, University of Virginia; Douglas Petkie, Wright State University and Tim Zwier, Purdue University. Any questions or suggestions about the Prize should be addressed to the Committee. Anyone (especially post-docs) willing to serve on a panel of judges should contact Brenda Winnewisser (winnewisser.2@osu.edu). Information ACCOMMODATIONS: The check-in for dormitory accommodations is located in Royer Activity Center off of Curl Drive. Royer Activity Center will open at 10:00a.m. Sunday, June 21, and remain open 24 hours a day through the Symposium. The dorm dining room will be open. Meal plans may be purchased upon registration. Inquire upon check-in. Other hotels close to campus include: The Blackwell, corner of Tuttle Park Place and Woodruff Avenue, 866-247-4003; Red Roof Inn, State Route 315 & Ackerman Rd., 614-267-9941; University Plaza Hotel, 3110 Olentangy River Rd., 614267-7461. NOTE: When making reservations with the University Plaza Hotel mention that you are with the Molecular Spectroscopy Symposium and you will be given the OSU discount, if available. MAIL: As in recent years, computer facilities for email will be available. Address your regular mail for delivery during the Symposium to: c/o MOLECULAR SPECTROSCOPY SYMPOSIUM, Department of Chemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio, 43210, U.S.A. FAX number - (614) 292-1948, Telephone number (614) 292-2569. PARKING: Parking permits, for the week, are available only from the check-in desk at Royer Activity Center. These permits allow you to park in any “C” parking space on campus. The permit must be displayed on the front windshield of your car. Please follow all traffic rules to avoid the issuance of tickets. NOTE: The Symposium takes place during the first week of Summer Quarter so parking on campus can be problemmatic. REGISTRATION: The Symposium Registration Desk will be located in Room 2017 McPherson Lab. It will be kept open between 4:00-6:00 p.m. Sunday, and 8:15a.m. - 4:30p.m., Monday through Friday. Those who have prepaid their registration and who are staying in the dorms will receive their registration packet at dormitory check-in. If you have prepaid your registration but are not staying at the dorms, pick up your packet at the Symposium Registration Desk. NOTE: If the dates of your stay change after Friday, June 12, please settle your dorm account with Royer Activity Center directly. LIABILITY: The Symposium fees DO NOT include provisions for the insurance of participants against personal injuries, sickness, theft or property damage. Participants and companions are advised to take whatever insurance they consider necessary. Neither the Symposium organizing committee, its sponsors, nor individual committee members assume any responsibility for loss, injury, sickness, or damages to persons or belongings, however caused. The statements and opinions stated during oral presentations or in written abstracts are solely the author’s responsibilities and do not necessarily reflect the opinions of the organizers. AUDIO/VIDEO INFORMATION: Overhead projectors and equipment for computer presentations, i.e. Powerpoint, will be available for each session. If you wish to do a computer presentation, you must go to the Digital Presentation link on our web site and follow the instructions. Your PowerPoint file and all supporting documents must be uploaded. These files must be submitted to the Symposium by midnight the day BEFORE your presentation session. All submitted files will be loaded on the presentation computer one half-hour prior to the beginning of the session. Please make careful note of the username (p#) and password provided in the email confirming receipt of your abstract - this username/password combination will be required when you submit your digital presentation. If you are submitting multiple presentations you will need to log on separately with the appropriate username and password for each presentation. ACKNOWLEDGEMENTS: The Symposium Chair wishes to acknowledge the hard work of numerous people who make this meeting possible. Key among these people are Becky Gregory, who solves everyone’s problems and keeps the meeting running smoothly; and my student assistants, Gabriel Just and Yvette Zuzeek who ensure the sessions go well. We wish to acknowledge the hospitality of the Chemistry Department in tolerating our invasion. Sergey Panov originally wrote the script for the electronic aspects of the Symposium; Computer Support, particularly Mike Reed, in Chemistry and Physics helps us modernize it as well as keep it and other aspects of our services operational. Finally, all the students in my group play vital roles in helping make sure nothing falls through the cracks. 1 MA. PLENARY SESSION MONDAY, JUNE 22, 2009 – 8:45 AM Room: AUDITORIUM, INDEPENDENCE HALL Chair: JAMES BEATTY, The Ohio State University, Columbus, Ohio Welcome Caroline C. Whitacre, Vice President for Research The Ohio State University 8:45 MA01 40 min 9:00 HELIUM DROPLETS AS NANO-CRYOSTATS FOR MOLECULAR SPECTROSCOPY: AGGREGATION, STATE SELECTION AND ELECTRON SPIN RESONANCE WOLFGANG E. ERNST, Institute of Experimental Physics, Graz University of Technology, Petersgasse 16, A-8010 Graz, Austria. MA02 40 min 9:45 ANION SLOW ELECTRON VELOCITY-MAP IMAGING (SEVI): APPLICATIONS TO SPECTROSCOPY AND DYNAMICS DANIEL M. NEUMARK, Department of Chemistry, University of California, Berkeley, CA 94720. Intermission RAO AWARDS Presentation of Awards by Brenda Winnewisser, Ohio State University 10:50 2008 Rao Award Winners Frank Filsinger, Max-Planck Jen Nicole Landry, University of Alberta Fumie Xe Sunahori, University of Kentucky COBLENTZ AWARD Presentation of Award by Andre Sommer, Miami University MA03 Coblentz Society Award Lecture 11:05 40 min 11:10 MOLECULAR SPECTROSCOPY: THE KEY TO UNDERSTANDING THE INTERSTELLAR MEDIUM BENJAMIN J. McCALL, Departments of Chemistry, Astronomy, and Physics, University of Illinois at Urbana-Champaign, Urbana, IL 61801. 2 MF. DYNAMICS MONDAY, JUNE 22, 2009 – 1:30 PM Room: 160 MATH ANNEX Chair: BERN KOHLER, The Ohio State University, Columbus, Ohio MF01 15 min 1:30 VIBRATIONAL MEDIATION OF PHOTOISOMERIZATION IN THE CONDENSED PHASE: TRANS-STILBENE KRISTIN A. BRINEY, DAVID S. BOUCHER, ADAM D. DUNKELBERGER, LESLIE V. HERMAN, F. FLEMING CRIM, The University of Wisconsin - Madison Department of Chemistry, 1101 University Avenue, Madison, WI 53705. MF02 ULTRAFAST STRUCTURAL DYNAMICS OF TRANS-STILBENE 10 min 1:47 JIE BAO, PETER WEBER, Chemistry Department, Brown University, Providence, RI 02912. MF03 15 min 1:59 EXCITED STATE ISOMERIZATION OF A STILBENE ANALOG: E / Z PHENYLVINYLACETYLENE JOSH J. NEWBY, CHRISTIAN W. MÜLLER, CHING-PING LIU a , HSIUPU D. LEE AND TIMOTHY S. ZWIER, Department of Chemistry, Purdue University, West Lafayette, IN 47907. a Current Address: Institute of Chemistry, Academia Sinica, Taipei, 11529 Taiwan. MF04 ULTRAFAST STUDIES OF PHOTOISOMERIZATION REACTIONS 15 min 2:16 NICOLE M. DICKSON, JESSICA E. DONEHUE, TERRY L. GUSTAFSON, The Ohio State University, Department of Chemistry, 100 W 18th Avenue, Columbus, OH 43210. MF05 15 min 2:33 CONFORMATIONAL ISOMERIZATION OF bis-(4-HYDROXYPHENYL)METHANE IN A SUPERSONIC JET EXPANSION, PART I: LOW BARRIER POTENTIAL ENERGY SURFACE IN THE STATE. CHIRANTHA P. RODRIGO, CHRISTIAN MÜLLER, WILLIAM H. JAMES III, NATHAN R. PILLSBURY, TIMOTHY S. ZWIER, Department of Chemistry, Purdue University, West Lafayette, IN 47907-2084. MF06 15 min 2:50 CONFORMATIONAL ISOMERIZATION OF bis-(4-HYDROXYPHENYL)METHANE IN A SUPERSONIC JET EXPANSION. PART II: INTERNAL MIXING AND LOW BARRIER POTENTIAL ENERGY SURFACE IN THE STATE. CHRISTIAN W. MÜLLER, CHIRANTHA P. RODRIGO, WILLIAM H. JAMES III, NATHAN R. PILLSBURY and TIMOTHY S. ZWIER, Department of Chemistry, Purdue University, West Lafayette, IN 479072084. Intermission 3 MF07 15 min 3:30 DYNAMICS OF DANGLING OD-STRETCH AT THE AIR/WATER INTERFACE BY HETERODYNE-DETECTED SFG SPECTROSCOPY I. V. STIOPKIN, C. WEERAMAN, F. SHALHOUT, A. V. BENDERSKII, Department of Chemistry, Wayne State University, Detroit, MI 48202. MF08 15 min 3:47 PHOTOPHYSICS OF PADDLEWHEEL COMPLEXES INVOLVING MOLYBDENUM OR TUNGSTEN QUADRUPLE BONDS SUPPORTED BY AMIDINATE AND CARBOXYLATE LIGANDS BRIAN G. ALBERDING and MALCOLM H. CHISHOLM, Ohio State University, Department of Chemistry, Columbus, Ohio 43210. MF09 15 min 4:04 THE PHOTOPHYSICAL PROPERTIES OF QUADRUPLY BONDED M ARYLETHYNYLCARBOXYLATE COMPLEXES CARLY R. REED and MALCOLM H. CHISHOLM and CLAUDIA TURRO, Ohio State University, Department of Chemistry, Columbus, Ohio 43210. MF10 15 min 4:21 ULTRAFAST HYDRATION DYNAMICS AND COUPLED WATER-PROTEIN FLUCTUATIONS IN APOMYOGLOBIN YI YANG, LUYUAN ZHANG, LIJUAN WANG, DONGPING ZHONG, Departments of Physics, Chemistry, and Biochemistry, The Ohio State University, Columbus, OH 43210. MF11 15 min 4:38 ULTRAFAST STUDIES OF RESONANCE ENERGY TRANSFER IN MYOGLOBIN: A-HELIX AND LOCAL CONFORMATIONAL FLUCTUATIONS JEFFREY A. STEVENS, JUSTIN J. LINK, YA-TING KAO, CHEN ZANG, LIJUN GUO, and DONGPING ZHONG, Department of Physics, The Ohio State University, Columbus, OH 43210. MF12 15 min 4:55 SUB-PICOSECOND INTERSYSTEM CROSSING AND VIBRATIONAL COOLING IN THE TRIPLET MANIFOLD OF 1-NITRONAPHTHALENE CHRISTIAN REICHARDT, R. AARON VOGT and CARLOS E. CRESPO-HERNÁNDEZ, Center for Chemical Dynamics, Department of Chemistry, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, Ohio 44106. 4 MG. INFRARED/RAMAN MONDAY, JUNE 22, 2009 – 1:30 PM Room: 170 MATH ANNEX Chair: MICHEL HERMAN, Université Libre de Bruxelles, Brussels, Belgium MG01 15 min 1:30 WATER NETWORK-DEPENDENT CHARGE TRANSLOCATION IN THE NO (H O) CLUSTERS: AN OLD RIDDLE OF THE IONOSPHERE BRINGS A MICROSCOPIC GROTTHUSS MECHANISM DOWN TO EARTH RACHAEL RELPH, BEN ELLIOTT, MICHAEL KAMRATH, MARK A. JOHNSON, Yale University, Department of Chemistry, P.O. Box 208107, New Haven, Connecticut 06520; ANNE B. MCCOY, The Ohio State University, Department of Chemistry, 100 West 18th Avenue, Columbus, Ohio 43210; ALBERT A. VIGGIANO, Air Force Research Laboratory, Space Vehicles Directorate, Hanscom Air Force Base, Massachusetts 01731; and ELDON E. FERGUSON, National Ocean & Atmospheric Administration, Climate Monitoring & Diagnostics Laboratory, Boulder, Colorado 80305. MG02 15 min 1:47 SPECTROSCOPIC INTERROGATION OF PHOTOINDUCED, SITE-TO-SITE MIGRATION OF SOLVENT MOLECULES IN WATER CLUSTER ANIONS TIMOTHY L. GUASCO, BEN M. ELLIOTT, MICHAEL Z. KAMRATH, and MARK A. JOHNSON, Sterling Chemistry Laboratory, Yale University, PO Box 208107, New Haven, CT 06520. MG03 15 min 2:04 GENERATING SPECTRA FROM GROUND STATE WAVE FUNCTIONS: UNRAVELING ANHARMONIC EFFECTS IN THE OH H O AND H O VIBRATIONAL PREDISSOCIATION SPECTRA ANNE B. McCOY, Department of Chemistry, The Ohio State University, Columbus, OH 43210. MG04 15 min 2:21 CONFIRMATION OF VIBRATION COUPLING IN THE SYMMETRIC CH STRETCH AS REVEALED BY COHERENCE-DETECTED FTMW-IR SPECTROSCOPY OF CH OD. SYLVESTRE TWAGIRAYEZU, TROCIA N. CLASP, DAVID S. PERRY, Department of Chemistry, The University of Akron, Akron OH 44325; JUSTIN L. NEILL, MATT T. MUCKLE, and BROOKS H. PATE, Department of Chemistry, University of Virginia, McCormick Rd., P.O. Box 400319, Charlottesville, VA 22904. MG05 10 min 2:38 COHERENCE-DETECTED FTMW-IR SPECTROSCOPY OF CH OD IN THE OD STRETCH REGION. SYLVESTRE TWAGIRAYEZU, DAVID S. PERRY, Department of Chemistry, The University of Akron, Akron OH 44325; JUSTIN L. NEILL, MATT T. MUCKLE, and BROOKS H. PATE, Department of Chemistry, University of Virginia, McCormick Rd., P.O. Box 400319, Charlottesville, VA 22904. Intermission 5 MG06 15 min 3:15 INFRARED SPECTROSCOPIC DEMONSTRATION OF COOPERATIVE STRENGTHENING OF AN INTRAMOLECULAR OH–O HYDROGEN BOND BY A WEAK CH–O COUNTERPART AMIT K SAMANTA, PRASENJIT PANDEY, BIMAN BANDYOPADHYAY AND TAPAS CHAKRABORTY , Physical Chemistry Department, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700032. MG07 15 min 3:32 STEPS TOWARD EXPERIMENTAL DETECTION OF MOLECULAR PARITY VIOLATION: ROVIBRATIONAL ANALYSIS OF THE CF-STRETCHING MODE AND FIRST OVERTONE OF CHFBrI S. ALBERT, K.K. ALBERT, M. QUACK, PHYSICAL CHEMISTRY, ETH Z ÜRICH, CH-8093 ZÜRICH, SWITZERLAND; S. BAUERECKER, INSTITUT FÜR TECHNISCHE UND PHYSIKALISCHE CHEMIE, TU BRAUNSCHWEIG, D-38106 BRAUNSCHWEIG, GERMANY. MG08 15 min 3:49 INFRARED SPECTROSCOPIC INVESTIGATION OF MAGIC NUMBER HYDRATED METAL ION CLUSTERS JORDAN P. BECK, JAMES M. LISY, Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, IL 61801. MG09 15 min 4:06 INFRARED SPECTROSCOPY OF SIZE-SELECTED PROTONATED MOLECULAR CLUSTERS: (N ) H , (CO) H , AND (O ) H , ALLEN M. RICKS, GARY E. DOUBERLY, and MICHAEL A. DUNCAN, Department of Chemistry, University of Georgia, Athens, Georgia 30602. MG10 15 min 4:23 INFRARED SPECTROSCOPY AND STRUCTURES OF METAL CARBONYL CATIONS, M(CO) (M= Nb,Ta,Mn), (n=1-11) Z. D. REED, A. M. RICKS, M. A. DUNCAN, Department of Chemistry, University of Georgia, Athens, GA 30602-2556. MG11 10 min 4:40 INFRARED SPECTRA OF ACETYLENE-NITROUS OXIDE TRIMERS: THE (N O) -C H AND (N O) -C D M. DEHGHANY, MAHIN AFSHARI, J. N. OLIAEE, N. MOAZZEN-AHMADI, Department of Physics and Astronomy, University of Calgary, Calgary, AB T2N 1N4, CANADA; A.R.W. MCKELLAR, Steacie Institute for Molecular Sciences, National Research Council of Canada, Ottawa, ON K1A 0R6, CANADA. MG12 NON-PLANAR STRUCTURES OF THE HIGH-ENERGY ROTATIONAL CONFORMERS OF 2-METHYLBUTA-1,3-DIENE (ISOPRENE) AND 2,3-DIMETHYLBUTA-1,3-DIENE 10 min 4:52 Yu. N. PANCHENKO, Dept. of Chemistry, M. V. Lomonosov Moscow State University, Moscow 119992, Russian Federation; Ch. W. BOCK, Dept. of Chemistry and Biochemistry, Philadelphia University, Philadelphia, PA 19144; J. D. LARKIN, Dept. of Chemistry, Bloomsburg University of Pennsylvania, Bloomsburg, PA 17815; A. V. ABRAMENKOV, Dept. of Chemistry, M. V. Lomonosov Moscow State University, Moscow 119992, Russian Federation; and F. K ÜHNEMANN, Institute of Applied Physics, Bonn University, 53115 Bonn, Germany. 6 MH. MICROWAVE MONDAY, JUNE 22, 2009 – 1:30 PM Room: 1000 McPHERSON LAB Chair: SONIA MELANDRI, Universita di Bologna, Bologna, Italy MH01 MICROWAVE SPECTROSCOPY OF SEVEN CONFORMERS OF 1,2-PROPANEDIOL 15 min 1:30 JUSTIN L. NEILL, MATT T. MUCKLE, and BROOKS H. PATE, Department of Chemistry, University of Virginia, McCormick Rd., P.O. Box 400319, Charlottesville, VA 22904-4319; F.J. LOVAS, D.F. PLUSQUELLIC, Optical Technology Division, NIST, Gaithersburg, MD 20899-8441; A.J. REMIJAN, National Radio Astronomy Observatory, 520 Edgemont Rd., Charlottesville, VA 22904-2475. MH02 MOLECULES WITH A SIX-FOLD BARRIER: MICROWAVE SPECTRUM OF TOLUENE 15 min 1:47 VADIM V. ILYUSHIN, Institute of Radio Astronomy of NASU, Chervonopraporna 4, 61002 Kharkov, Ukraine; ZBIGNIEW KISIEL, LECH PSZCZ ÓLKOWSKI, Institute of Physics, Polish Academy of Sciences, Al. Lotników 32/46, 02-668 Warszawa, Poland; HEINRICH M ÄDER, Institut für Physikalische Chemie, Christian-Albrechts Universität zu Kiel, Olshausenstrasse 40, D-24098, Kiel, Germany; JON T. HOUGEN, Optical Technology Division, National Institute of Standards and Technology, Gaithersburg, MD 20899-8441. MH03 15 min 2:04 INTERACTION OF THE HYPERFINE COUPLING AND THE INTERNAL ROTATION IN METHYL FORMATE a M. TUDORIE, D. JEGOUSO, G. SEDES, T. R. HUET, Laboratoire de Physique des Lasers, Atomes et Molécules (PhLAM) UMR 8523 CNRS, B ât. P5, Université des Sciences et Technologies de Lille 1, 59655 Villeneuve d’Ascq Cedex, France; and L. H. COUDERT, LISA, CNRS/Universit és Paris 12 et 7, 61 Avenue du Général de Gaulle, 94010 Créteil, France. a This work is supported by the ANR-08-BLAN-0054 contract MH04 15 min 2:21 ASSIGNMENT OF THE SUB-MILLIMETER WAVE SPECTRUM OF METHYL CARBAMATE, NH COOCH , IN THE FIRST EXCITED STATE OF THE METHYL GROUP INTERNAL ROTATION P. GRONER, Department of Chemistry, University of Missouri-Kansas City, Kansas City, MO 64110-2499. MH05 15 min 2:38 FORBIDDEN TRANSITIONS IN THE VERY RICH PURE ROTATIONAL SPECTRUM OF TRANS-1IODOPERFLUOROPROPANE CHRISTOPHER T. DEWBERRY, GARRY S. GRUBBS II, and STEPHEN A. COOKE, The Department of Chemistry, University of North Texas, P.O. Box 305070, Denton, TX, 76203-5070. MH06 SOME EFFECTS OF SUCCESSIVE FLUORINATION ON 1-IODOPROPANE 15 min 2:55 GARRY S. GRUBBS II, CHRISTOPHER T. DEWBERRY, and STEPHEN A. COOKE, The Department of Chemistry, University of North Texas, P.O. Box 305070, Denton, TX, 76203-5070. 7 MH07 ROTATIONAL SPECTRA OF HALOGENATED ETHERS USED AS VOLATILE ANAESTHETICS 15 min 3:12 ALICIA VEGA-TORIBIO and ALBERTO LESARRI, Departamento de Quı́mica Fı́sica y Quı́mica Inorgánica, Facultad de Ciencias, Universidad de Valladolid, E-47011 Valladolid, Spain; RICHARD D. SUENRAM, Department of Chemistry, University of Virginia, Charlottesville, VA 22904, USA; JENSUWE GRABOW, Institut für Physikalische Chemie und Elektrochemie, Leibniz Universit ät Hannover, Callinstraße 3 - 3A, D-30167 Hannover, Germany. MH08 15 min 3:29 ISOTOPOLOGUE-SENSITIVE DETECTION USING CHIRPED-PULSE FT-MW SPECTROSCOPY: MINOR SPECIES OF PROPOFOL ALBERTO LESARRI, Departamento de Quı́mica Fı́sica y Quı́mica Inorgánica, Facultad de Ciencias, Universidad de Valladolid, E-47011 Valladolid, Spain; JUSTIN NEILL, MATT MUCKLE, STEVEN T. SHIPMAN, BROOKS H. PATE and RICHARD D. SUENRAM, Department of Chemistry, University of Virginia, Charlottesville, VA 22904, USA; WALTHER CAMINATI, Dipartimento di Chimica ”G. Ciamician”, Università di Bologna, I-40126 Bologna, Italy. Intermission MH09 15 min 4:00 HIGH RESOLUTION INVESTIGATION OF SILACYCLOBUTANE USING FTMW AND SYNCHROTRON BASED FTIR SPECTROSCOPY CODY VAN DIJK, SAMANTHA VAN NEST, ZIQIU CHEN and JENNIFER VAN WIJNGAARDEN, Department of Chemistry, University of Manitoba, Winnipeg MB R3T 2N2 Canada. MH10 ROTATIONAL SPECTRA OF THE ANTI-ANTI CONFORMER OF N-BUTYLGERMANE 10 min 4:17 SEAN A. PEEBLES, REBECCA A. PEEBLES, AMANDA L. STEBER, and DANIEL A. OBENCHAIN, Department of Chemistry, Eastern Illinois University, 600 Lincoln Avenue, Charleston, IL 61920; GAMIL A. GUIRGIS, Department of Chemistry and Biochemistry, The College of Charleston, 66 George Street, Charleston, SC 29424; HOWARD D. STIDHAM, Department of Chemistry, University of Massachusetts, 710 North Pleasant Street, Amherst, MA 01003. MH11 15 min 4:29 ROTATIONAL SPECTROSCOPY OF TWO TELLUROL COMPOUNDS : ETHYL AND VINYL-TELLUROL R. MOTIYENKO, L. MARGULÈS, M. GOUBET, Laboratoire PhLAM, CNRS UMR 8523, Universit é de Lille 1, 59655 Villeneuve d’Ascq Cedex, France; H. MØLLENDAL, Centre for Theoretical and Computational Chemistry (CTCC), University of Oslo, P.O. Box 1033, Blindern, NO-0315 Oslo, Norway; and J. C. GUILLEMIN, Sciences Chimiques de Rennes-Ecole Nationale Sup érieure de Chimie de RennesCNRS, 35700 Rennes, France. MH12 ROTATIONAL SPECTRA OF ADRENALINE AND NORADRENALINE 15 min 4:46 V. CORTIJO, J. C. LÓPEZ, and J. L. ALONSO, Grupo de Espectroscopı́a Molecular (GEM), Departamento de Quı́mica Fı́sica y Quı́mica Inorgánica, Facultad de Ciencias, Universidad de Valladolid, E-47005 Valladolid, Spain. 8 MH13 10 min 5:03 MEASUREMENT OF NITROGEN HYPERFINE STRUCTURE ON THE 53 CM (562 MHz) BUTYRONITRILE LINE CHRISTOPHER T. DEWBERRY, GARRY S. GRUBBS II, ANDREW RAPHELTa and STEPHEN A. COOKE, The Department of Chemistry, University of North Texas, P.O. Box 305070, Denton, TX, 762035070. a NSF-REU student from Concordia University, Nebraska MH14 MICROWAVE SPECTROSCOPY OF 2-FURANCARBOXYLIC ACID 15 min 5:15 R. MOTIYENKOa , M. GOUBET, L. MARGULÈS, G. WLODARCZAK, Laboratoire PhLAM, CNRS UMR 8523, Université de Lille 1, 59655 Villeneuve d’Ascq Cedex, France; E. A. ALEKSEEV, S. F. DYUBKO, Institute of Radio Astronomy of NASU, Chervonopraporna 4, 61002 Kharkov, Ukraine. a The support of INTAS YSF (INTAS Ref. Nr 06-1000014-5984) is gratefully acknowledged MH15 15 min 5:32 ROTATIONAL SPECTRA OF -, -, AND -CYANOPHENOL AND INTERNAL ROTATION OF -CYANOPHENOL ANDREW R. CONRAD, NATHAN Z. BAREFOOT, and MICHAEL J. TUBERGEN, Department of Chemistry, Kent State University, Kent, Ohio 44242. 9 MI. ELECTRONIC MONDAY, JUNE 22, 2009 – 1:30 PM Room: 1015 McPHERSON LAB Chair: SANG KUK LEE, Pusan National University, Pusan, Korea MI01 15 min 1:30 APPLICATION OF THE ’MLR’ DIRECT POTENTIAL FITTING (DPF) METHOD FOR THE STATE OF Cs JOHN A. COXON, Department of Chemistry, Dalhousie University, Halifax, Nova Scotia B3H 4J3, Canada; PHOTOS G. HAJIGEORGIOU, Department of Life and Health Sciences, University of Nicosia, 46 Makedonitissas Avenue, P.O Box 24005, 1700 Nicosia, Cyprus. MI02 15 min 1:47 AN EXTENSION OF THE ‘MLR’ POTENTIAL FUNCTION FORM WHICH ALLOWS FOR AN ACCURATE DPF TREATMENT OF Li , WHICH COUPLES TO TWO OTHER STATES NEAR THEIR ASYMPTOTES NIKESH S. DATTANI and ROBERT J. LE ROY, Department of Chemistry, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada; AMANDA J. ROSS, Universit é de Lyon F-69622, Lyon, France; Universit é Lyon 1, Villeurbanne; CNRS, UMR5579, LASIM; COLAN LINTON, Physics Department, University of New Brunswick, Fredericton, New Brunswick E3B 5A3, Canada. MI03 15 min 2:04 THEORETICAL AND SPECTROSCOPIC INVESTIGATIONS OF ALKALI METAL-RARE GAS INTERACTION POTENTIALS JIANDE HAN, JEREMY M. MERRITT and MICHAEL C. HEAVEN, Department of Chemistry, Emory University, Atlanta, GA 30322. MI04 15 min 2:21 ONE- AND TWO-PHOTON SPECTROSCOPY OF ALKALI ATOMS ON HELIUM NANODROPLETS AT 3 eV ENERGY ALEXANDRA PIFRADER, OLIVIER ALLARD, GERALD AUBÖCK, CARLO CALLEGARI, and WOLFGANG E. ERNST, Institute of Experimental Physics, TU Graz, Petersgasse 16, 8010 Graz, Austria/EU; FRANCESCO ANCILOTTO, INFM - Dipartimento di Fisica, Universit à di Padova, Via Marzolo 8, I-35131 Padova Italy. MI05 15 min 2:38 ROTATIONALLY RESOLVED SPECTROSCOPY OF THE ELECTRONICALLY EXCITED C AND D STATES OF XeKr AND XeAr LORENA PITICCO, MARTIN SCHÄFER, and FRÉDÉRIC MERKT, ETH Zürich, Laboratorium f ür Physikalische Chemie, Wolfgang-Pauli-Strasse 10, 8093 Z ürich, Switzerland. MI06 TWO-PHOTON RESEONANT SECOND HARMONIC GENERATION IN ATOMIC XEON 15 min 2:55 Y. J. SHI, W. AL-BASHEER, Department of Chemistry, University of Calgary, Calgary, Alberta, T2N 1N4; R. I. THOMPSON, Department of Physics and Astronomy, University of Calgary, Calgary, Alberta, T2N 1N4. 10 Intermission MI07 15 min 3:30 A NEW ONE-ELECTRON EFFECTIVE POTENTIAL FOR CaF BASED ON AB-INITIO CALCULATIONS STEPHEN L. COY, Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139; BRYAN M. WONG, Sandia National Laboratory, Livermore, CA 94551-0969; and ROBERT W. FIELD, Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139. MI08 15 min 3:47 ADAPTIVE ANALYTIC MAPPING PROCEDURES FOR SIMPLE AND ACCURATE CALCULATION OF SCATTERING LENGTHS AND PHOTOASSOCIATION ABSORPTION INTENSITIES ROBERT J. LE ROY, Guelph-Waterloo Centre for Graduate Work in Chemistry and Biochemistry, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada; VLADIMIR V. MESHKOV and ANDREJ V. STOLYAROV, Department of Chemistry, Moscow State University, GSP-2 Leninskie Gory 1/3, Moscow 119991, Russia. MI09 15 min 4:04 DETERMINATION OF THE Be (X) POTENTIAL ENERGY CURVE USING STIMULATED EMISSION PUMPING SPECTROSCOPY J. M. MERRITT, V. E. BONDYBEY, and M. C. HEAVEN, Department of Chemistry, Emory University, Atlanta, GA 30322. MI10 15 min 4:21 IONIZATION ENERGY MEASUREMENTS AND SPECTROSCOPY OF THE BeOBe MOLECULE J. M. MERRITT, V. E. BONDYBEY, and M. C. HEAVEN, Department of Chemistry, Emory University, Atlanta, GA 30322. MI11 15 min 4:38 DETERMINATION OF THE IONIZATION AND DISSOCIATION ENERGIES OF MOLECULAR HYDROGEN, H JINJUN LIU, URS HOLLENSTEIN, and FR ÉDÉRIC MERKT, Laboratorium f ür Physikalische Chemie, ETH-Zürich, 8093 Z ürich, Switzerland; EDCEL J. SALUMBIDES, JEROEN C. J. KOELEMEIJ, KJELD S. E. EIKEMA, and WIM UBACHS, Laser Centre, Department of Physics and Astronomy, Vrije Universiteit, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands. MI12 PHOTOELECTRON SPECTROSCOPY AND DYNAMICS OF ICN 15 min 4:55 ELISA M. MILLER, LEONID SHEPS, and W. CARL LINEBERGER, JILA, Department of Chemistry and Biochemistry, University of Colorado at Boulder, Boulder, CO 80309. MI13 THEORETICAL STUDIES OF TIME-RESOLVED PHOTOELECTRON SPECTRA OF IBr 15 min 5:12 SAMANTHA HORVATH, ANNE B. McCOY, and RUSSELL M. PITZER, Department of Chemistry, The Ohio State University, Columbus, OH 43210. 11 MI14 15 min 5:29 TWO PHOTON EXCITATION OF MOLECULAR IODINE. AN ADVANCED LASER TECHNIQUE FOR THE UNDERGRADUATE PHYSICAL CHEMISTRY LAB W. BRYAN LYNCH, MEGAN J. GOOTEE, and MARC P. CHAVEZ, Department of Chemistry, University of Evansville, Evansville, IN 47722. MI15 10 min 5:46 FOURIER-TRANSFORM SPECTROSCOPY OF I (- ) EMISSION FOLLOWING OPTICAL-OPTICAL DOUBLE RESONANCE EXCITATION OF THE I ( ) STATE VADIM A. ALEKSEEV, Institute of Physics, St.Petersburg State University, Peterhof, 198504 Russia; AMANDA J. ROSS, Laboratoire de Spectrométrie Ionique et Moléculaire, Université’ de Lyon (Lyon 1), 69622 Villeurbanne, France. 12 MJ. MATRIX/CONDENSED PHASE MONDAY, JUNE 22, 2009 – 1:30 PM Room: 2015 McPHERSON LAB Chair: WOLFGANG ERNST, Technische Universität Graz, Graz, Austria MJ01 15 min 1:30 OPTICALLY-DETECTED MAGNETIC RESONANCE OF ALKALI ATOMS ISOLATED ON HELIUM NANODROPLETS MARKUS KOCH, CARLO CALLEGARI, WOLFGANG E. ERNST, Institute of Experimental Physics, TU Graz, Petersgasse 16, 8010 Graz, Austria. MJ02 15 min 1:47 HELIUM NANODROPLET ISOLATION SPECTROSCOPY USING AN EXTERNAL CAVITY QUANTUM CASCADE LASER ALEX MORRISON and GARY E. DOUBERLY, Department of Chemistry, University of Georgia, Athens, Georgia 30602. MJ03 15 min 2:04 ROTATIONAL SPECTROSCOPY OF CARBON MONOXIDE SOLVATED WITH PARA-HYDROGEN MOLECULES PAUL L. RASTON AND WOLFGANG JÄGER, Department of Chemistry, University of Alberta, Edmonton, Alberta T6G-2G2, Canada. MJ04 15 min 2:21 ROVIBRATIONAL SATELLITE BANDS OF THE Br SPIN-ORBIT TRANSITION IN Br DOPED SOLID PARAHYDROGEN DAVID T. ANDERSON, Department of Chemistry, University of Wyoming, Laramie, WY 82071-3838. MJ05 15 min 2:38 INVESTIGATION OF THE AMIDE I BAND OF N-METHYLACETAMIDE IN SOLID PARAHYDROGEN USING FTIR SPECTROSCOPY LEIF O. PAULSON and DAVID T. ANDERSON, Department of Chemistry, University of Wyoming, Laramie, WY 82071-3838. MJ06 CARS STUDY OF LIQUID PARA-HYDROGEN AT DIFFERENT TEMPERATURES 15 min 2:55 RUSSELL SLITER, MICHAEL MAKRIS and ANDREY F. VILESOV, Department of Chemistry, University of Southern California, Los Angeles, CA 90089. 13 MJ07 10 min 3:12 ROTATION AND MATRIX EFFECTS ON THE EPR SPECTRA OF METHYL RADICALS TRAPPED IN GAS SOLIDS YURIJ A. DMITRIEVa , Ioffe Physical-Technical Institute, 26 Politekhnicheskaya str.,194021 St. Petersburg, Russia; and NIKOLAS-PLOUTARCH BENETIS, Department of Pollution Control, Technological Educational Institution, TEI, West Macedonia, Kozani 501 00, Greece. a Support by Russian Foundation for Basic Research under grant 08-02-90409-Ukr a is gratefully acknowledged Intermission MJ08 10 min 3:40 SPECTROSCOPY OF THE I MOLECULE IN CRYOGENIC MATRICES OF FLUORINE CONTAINING MOLECULES. VADIM A. ALEKSEEV a , Insititute of Physics, St.Petersburg State University, 198504 St.Petersburg, Russia; CHRISTINE PRENDERGAST, JOHN G. McCAFFREY, Department of Chemistry, National University of Ireland, Maynooth, Ireland. a Support by Science Foundation of Ireland via Walton Visitor Award (07/W.1/I1819) is gratefully acknowledged MJ09 15 min 3:52 CHARACTERIZATION OF A WATER-HEXAFLUOROBENZENE COMPLEX USING MATRIX ISOLATION INFRARED SPECTROSCOPY JAY C. AMICANGELO, DANIEL G. IRWIN, CYNTHIA J. LEE, and NATALIE C. ROMANO, NANCY L. SAXTON, School of Science, Penn State Erie, Erie, PA 16563. MJ10 VIBRATIONAL OVERTONE SPECTRA OF AND IN CRYOGENIC LIQUIDS 15 min 4:09 MARIA H. DIEZ-Y-RIEGA and CARLOS E. MANZANARES, Department of Chemistry and Biochemistry, Baylor University, Waco, Texas, 76798. MJ11 PHOTOCHEMISTRY OF MATRIX-ISOLATED VINYL ACETATE 15 min 4:26 KRISTA COHEN and C. A. BAUMANN, Department of Chemistry, The University of Scranton, Scranton, PA 18510-4626. MJ12 MECHANISM OF THE THERMAL DECOMPOSITION OF FURAN 15 min 4:43 ANGAYLE VASILIOU, G. BARNEY ELLISON, University of Colorado, Boulder, CO 80309-0215; MARK R. NIMLOS, Center for Renewable Chemical, Technologies & Materials, NREL, 1617 Cole Blvd., Golden, CO 80401; JOHN W. DAILY, Department of Mechanical Engineering, University of Colorado, Boulder, CO 80309-0427. MJ13 15 min 5:00 MILLIMETER-WAVE SPECTRA OF CARBON MONOXIDE SOLVATED WITH HELIUM ATOMS L. A. SURIN, T. F. GIESEN, S. SCHLEMMER, I. Physikalisches Institut, University of Cologne, 50937 Cologne, Germany; A. V. POTAPOV, B. S. DUMESH, Institute of Spectroscopy of Russian Academy of Sciences, 142190 Troitsk, Moscow region, Russia. 14 MJ14 Post-deadline Abstract – Original Abstract Withdrawn 15 min 5:17 HENDI SPECTROSCOPY OF C-H STRETCHING MODES OF METHANE AND SUBSTITUTED METHANE MOLECULES ROBERT R. FEHNEL and KEVIN K. LEHMANN, Department of Chemistry, University of Virginia, Charlottesville VA, 22904-4319. 15 TA. MICROWAVE TUESDAY, JUNE 23, 2009 – 8:30 AM Room: 160 MATH ANNEX Chair: VADYM ILYUSHYN, Institue of Radio Astronomy, Kharkiv, Ukraine TA01 GAS PHASE STRUCTURE OF AMINO ACIDS: LA-MB-FTMW STUDIES 15 min 8:30 I. PENA S. MATA, M. E. SANZ, V. VAQUERO, C. CABEZAS, C. PEREZ, S. BLANCO, J. C. L ÓPEZ, and J. L. ALONSO, Grupo de Espectroscopı́a Molecular (GEM), Departamento de Quı́mica Fı́sica y Quı́mica Inorgánica, Facultad de Ciencias, Universidad de Valladolid, E-47005 Valladolid, Spain. TA02 PROBING GUANINE AND CYTOSINE TAUTOMERS IN THE GAS PHASE 15 min 8:47 I. PENA, V. VAQUERO, J. C. LÓPEZ, and J. L. ALONSO, Grupo de Espectroscopı́a Molecular (GEM), Departamento de Quı́mica Fı́sica y Quı́mica Inorgánica, Facultad de Ciencias, Universidad de Valladolid, E-47005 Valladolid, Spain. TA03 ROTATIONAL SPECTRA OF PHENYLALANINE, TIROSINE AND TRYPTOPHAN 15 min 9:04 S. MATA, C. PEREZ, M. E. SANZ, S. BLANCO, J. C. L ÓPEZ, and J. L. ALONSO, Grupo de Espectroscopı́a Molecular (GEM), Departamento de Quı́mica Fı́sica y Quı́mica Inorgánica, Facultad de Ciencias, Universidad de Valladolid, E-47005 Valladolid, Spain. TA04 15 min 9:21 THE STUDY OF SMALL BIOMOLECULES USING CHIRPED-PULSE FOURIER TRANSFORM MICROWAVE (CPFTMW) SPECTROMETER IN THE GAS PHASEa RYAN G. BIRD and DAVID W. PRATT, Department of Chemistry, University of Pittsburgh, Pittsburgh, Pa 15213; JUSTIN L. NEILL and BROOKS H. PATE, Department of Chemistry, University of Virginia, Charlottesville, Va 22904. a Work supported by NSF (CHE-0618740). TA05 15 min 9:38 CHIRPED PULSE-FOURIER TRANSFORM MICROWAVE SPECTROSCOPY OF ETHYL 3-METHYL-3PHENYLGLYCIDATE (STRAWBERRY ALDEHYDE) STEVEN T. SHIPMAN, Department of Natural Sciences, New College of Florida, Sarasota, FL; JUSTIN L. NEILL, MATT T. MUCKLE, RICHARD D. SUENRAM, and BROOKS H. PATE, Department of Chemistry, University of Virginia, Charlottesville, VA 22904. 16 TA06 THE ROTATIONAL SPECTRUM OF TERTIARY-BUTYL ALCOHOL 15 min 9:55 E. A. COHEN, B. J. DROUIN, Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109-8099; E. A. VALENZUELA a, R. C. WOODS, Department of Chemistry, University of Wisconsin, Madison WI 53706-1322; W. CAMINATI, A. MARIS, and S. MELANDRI, Dipartimento di Chimica “G. Ciamician” dell’Università, Via Selmi 2, I-40126 Bologna, Italy. a Present address, 4901 Oakridge Dr. Midland, MI 48640-1919 Intermission TA07 15 min MICROWAVE SPECTROSCOPIC MEASUREMENTS OF THE ROTATIONAL SPECTRUM OF METHYL CYCLOPENTADIENYL IRON DICARBONYL 10:30 CHAKREE TANJAROON and STEPHEN G. KUKOLICH a , Department of Chemistry, The University of Arizona, Tucson, Arizona 85721. a Support by NSF research grant is gratefully acknowledged TA08 MICROWAVE STUDIES OF PERFLUOROPENTANE AND ITS HELICITY 15 min 10:47 JOSEPH A. FOURNIER, ROBERT K. BOHN, Dept. of Chemistry, Univ. of Connecticut, Storrs, CT 062693060; JOHN A. MONTGOMERY, JR., Dept. of Physics, Univ. of Connecticut, Storrs, CT 06269-3046. TA09 15 min 11:04 ANALYSIS OF THE ROTATIONAL SPECTRA OF 2,3,4,5,6-PENTAFLUOROTOLUENE AND 1-CHLORO-2,3,4,5,6PENTAFLUOROBENZENE ASHLEY A. OSTHOFF, REBECCA A. PEEBLES, SEAN A. PEEBLES, Department of Chemistry, Eastern Illinois University, 600 Lincoln Ave., Charleston, IL 61920; GARRY S. GRUBBS II, STEPHEN A. COOKE, Department of Chemistry, University of North Texas, PO Box 305070, Denton, TX 76203; BROOKS H. PATE, JUSTIN L. NEILL, MATT T. MUCKLE, Department of Chemistry, University of Virginia, McCormick Rd., PO Box 400319, Charlottesville, VA 22904. TA10 15 min 11:21 THE DIFFERENCES IN THE ROLE OF O AND S ATOMS IN THE MOLECULAR STRUCTURE AND DYNAMICS OF SOME COMPLEXES YOSHIYUKI KAWASHIMA, AKINORI SATO and YOSHIO TATAMINTANI, Department of Applied Chemistry, Faculty of Engineering, Kanagawa Institute of Technology, Atsugi, Kanagawa 243-0292, JAPAN; NOBUKIMI OHASHI, Kanazawa University, 920-1192, JAPAN; JAMES M. LOBUE, Department of Chemistry, Georgia Southern University, Statesboro, GA 30460, USA; EIZI HIROTA, The Graduate University for Advanced Studies, Hayama, Kanagawa 240-0193, JAPAN. TA11 FOURIER TRANSFORM MICROWAVE SPECTRA OF -BUTANOL AND ISOBUTANOL 15 min 11:38 TAIGO UZUYAMA, YUGO TANAKA, and YOSHIYUKI KAWASHIMA, Department of Applied Chemistry, Faculty of Engineering, Kanagawa Institute of Technology, Atsugi, Kanagawa 243-0292, JAPAN; EIZI HIROTA, The Graduate University for Advanced Studies, Hayama, Kanagawa 240-0193, JAPAN. 17 TA12 15 min 11:55 ANALYSIS OF THE ROTATIONAL STRUCTURE IN A C-TYPE BAND IN THE HIGH-RESOLUTION INFRARED SPECTRUM OF -1,4-DIFLUOROBUTADIENE-1- NORMAN C. CRAIG, CHRISTOPHER F. NEESE, and DEACON J. NEMCHICK, Department of Chemistry and Biochemistry, Oberlin College, Oberlin, OH 44074; MICHAEL LOCK, Physikalish-Chemisches Institut der Justus Liebig Universität, Heinrich-Buff Ring 58, D-35392, Giessen, Germany. 18 TB. ELECTRONIC TUESDAY, JUNE 23, 2009 – 8:30 AM Room: 170 MATH ANNEX Chair: MASAAKI BABA, Kyoto University, Kyoto, Japan TB01 15 min 8:30 HIGH RESOLUTION ELECTRONIC SPECTROSCOPY OF 2,6-DIAMINOPYRIDINE IN THE GAS PHASE a CASEY L. CLEMENTS, ADAM J. FLEISHER, JUSTIN W. YOUNG, JESSICA A. THOMAS, AND DAVID W. PRATT, Department of Chemistry, University of Pittsburgh, Pittsburgh, PA 15260. a Work supported by NSF (CHE-0615755). TB02 15 min 8:47 CHARACTERIZATION OF STRUCTURAL ISOMERS OF NAPHTHALENE: ELECTRONIC SPECTROSCOPY OF Z-PHENYLVINYLACETYLENE JOSH J. NEWBY, CHRISTIAN W. MÜLLER, CHING-PING LIUa , WILLIAM H. JAMES III, EVAN G. BUCHANAN, HSIUPU D. LEE, AND TIMOTHY S. ZWIER, Department of Chemistry, Purdue University, West Lafayette, IN 47907. a Current Address: Institute of Chemistry, Academia Sinica, Taipei, 11529 Taiwan. TB03 FLUORESCENCE SPECTROSCOPY OF JET-COOLED 1-PHENYL-1-BUTYN-3-ENE 15 min 9:04 JOSHUA A. SEBREE,TIMOTHY S. ZWIER, Department of Chemistry, Purdue University, West Lafayette, IN 47909-2084. TB04 15 min 9:21 HIGH-RESOLUTION THRESHOLD PHOTOIONIZATION AND PHOTOELECTRON SPECTROSCOPY OF PROPENE AND 2-BUTYNE JULIE M. MICHAUD, KONSTANTINA VASILATOU and FR ÉDÉRIC MERKT, LABORATORIUM FÜR PHYSIKALISCHE CHEMIE, ETH ZÜRICH, 8093 ZÜRICH, SWITZERLAND. Intermission TB05 15 min 10:00 ACID-BASE ELECTRONIC PROPERTIES IN THE GAS PHASE: PERMANENT ELECTRIC DIPOLE MOMENTS OF A PHOTOACIDIC SUBSTRATE.a ADAM J. FLEISHER, PHILIP J. MORGAN and DAVID W. PRATT, Department of Chemistry, University of Pittsburgh, 15260. a Work supported by NSF (CHE-0615755). 19 TB06 1-PHENYLPYRROLE A TICT MOLECULE?. a 15 min 10:17 JESSICA A. THOMAS, JUSTIN W. YOUNG, ADAM J. FLEISHER, CASEY L. CLEMENTS, and DAVID W. PRATT, Department of Chemistry, University of Pittsburgh, Pittsburgh, PA 15260; LEONARDO ALVAREZ-VALTIERRA, Division de Ciencias e Ingenierias, Campus Leon, Universidad de Guanajuato, Leon, Gto. 37150, Mexico. a Work supported by NSF CHE-0615755 TB07 15 min 10:34 EVOLUTION OF THE MLCT BAND FOLLOWING CHANGES IN OXIDATION STATE FOR HIGHLY COUPLED MIXED VALENCE COMPLEXES BENJAMIN J. LEAR and MALCOLM H. CHISHOLM, The Ohio State University, Department of Chemistry, Columbus, Ohio 43210. TB08 15 min EFFECTS OF METHYLATION ON ZEBULARINE STUDIED BY DENSITY FUNCTIONAL THEORY 10:51 LALITHA SELVAM, VLADISLAV VASILYEV and FENG WANG, Centre for Molecular Simulation, Faculty of ICT, Swinburne University of Technology, Hawthorn, Victoria 3122,Australia; VLADISLAV VASILYEV, National Computational Infrastructure, Australian National University, Canberra, ACT 0200,Australia (Corresponding email:lselvam@ict.swin.edu.au). TB09 15 min 11:08 CONFORMATION-SPECIFIC ELECTRONIC AND VIBRATIONAL SPECTROSCOPY OF DIBENZO-15-CROWN-5 ETHER IN A SUPERSONIC JET. EVAN G. BUCHANAN, CHIRANTHA P. RODRIGO, WILLIAM H. JAMES III, JOSH J. NEWBY, and TIMOTHY S. ZWIER, Department of Chemistry, Purdue University, West Lafayette, IN 47907. TB10 15 min 11:25 WATER’S ROLE IN RESHAPING A MACROCYCLE’S BINDING POCKET: CONFORMATION-SPECIFIC INFRARED AND ULTRAVIOLET SPECTROSCOPY OF BENZO-15-CROWN-5- -CLUSTERS V. ALVIN SHUBERT, Argonne National Laboratory, Chemical Sciences and Engineering Division, 9700 South Cass Avenue, Argonne, IL 60439; CHRISTIAN W. M ÜLLER, WILLIAM H. JAMES III and TIMOTHY S. ZWIER, Department of Chemistry, Purdue University, West Lafayette, IN 47907-2084. TB11 10 min EFFECT OF SOLVENT ON PHOTO PHYSICAL CHARACTERISTICS OF SUBSTITUTED COUMARINS 11:42 RAJESH GIRI, DEPARTMENT OF FHYSICS AND ELECTRONICS, RAJDHANI COLLEGE, UNIVERSITY OF DELHI, RAJA GARDEN, NEW DELHI, INDIA; ,. 20 TC. MINI-SYMPOSIUM: FIR/THz AIR/SPACE MISSIONS TUESDAY, JUNE 23, 2009 – 8:30 AM Room: 1000 McPHERSON LAB Chair: LI-HONG XU, University of New Brunswick, Saint John, NB, Canada TC01 Journal of Molecular Spectroscopy Review Lecture 30 min 8:30 HOW CAN SYNCHROTRON-BASED FTIR SPECTROSCOPY CONTRIBUTE TO ASTROPHYSICAL AND ATMOSPHERIC DATA NEEDS? A.R.W. McKELLAR, Steacie Institute for Molecular Sciences, National Research Council of Canada, Ottawa, ON K1A 0R6, Canada. TC02 15 min 9:05 THE HIGH RESOLUTION FAR-INFRARED SPECTRUM OF METHANE AT THE SOLEIL SYNCHROTRON V. BOUDON, Institut Carnot de Bourgogne, UMR 5209 CNRS-Universit é de Bourgogne, 9. Av. A. Savary, BP 47870, F-21078 Dijon Cedex, France; O. PIRALI, P. ROY, Ligne AILES – Synchrotron SOLEIL, L’Orme des Merisiers, F-91192 Gif-sur-Yvette, France; L. MANCERON, Laboratoire de Dynamique, Interactions et Réactivité, UMR 7075 - Universit Pierre et Marie Curie - CNRS, Case 49, 4 Place Jussieu, F-75252, Paris Cedex, France; J. VANDER AUWERA, Service de Chimie Quantique et Photophysique, Universit é Libre de Bruxelles, CP 160/09, 50 avenue F.D. Roosevelt - B-1050 Brussels, Belgium. TC03 15 min 9:22 FOURIER TRANSFORM MICROWAVE AND INFRARED SPECTROSCOPIC INVESTIGATION OF PROPIOLACTONE ZIQIU CHEN and JENNIFER VAN WIJNGAARDEN, Department of Chemistry, University of Manitoba, Winnipeg MB R3T 2N2 Canada. TC04 15 min 9:39 THz SPECTROSCOPY OF H D F. MATSUSHIMA, T. YONEZU, Y. MORIWAKI, and K. TAKAGI, Department of Physics, University of Toyama, Gofuku, Toyama 930-8555, Japan; T. AMANO, Department of Chemistry, University of Waterloo, Waterloo, Canada N2L 3G1. TC05 15 min 9:56 LABORATORY STUDIES OF THE FORMATION OF INTERSTELLAR DUST FROM MOLECULAR PRECURSORS CESAR S. CONTRERAS and FARID SALAMA, Space Science Division, NASA-Ames Research Center, Moffett Field, CA, USA. Intermission 21 TC06 THE SUBMILLIMETER SPECTRUM OF CH CH CN IN ITS GROUND VIBRATIONAL STATEa 15 min 10:30 CAROLYN S. BRAUER, JOHN C. PEARSON, BRIAN J. DROUIN, SHANSHAN YU, JET PROPULSION LABORATORY, CALIFORNIA INSTITUTE OF TECHNOLOGY, 4800 OAK GROVE DR., PASADENA, CA 91109. a Research described in this paper was performed at the Jet Propulsion Laboratory, California Institute of Technology, under contracts and cooperative agreements with the National Aeronautics and Space Administration. TC07 15 min 10:47 ANALYSIS OF THE LOWEST IN-PLANE BEND AND FIRST EXCITED TORSIONAL STATE OF CH CH CNa CAROLYN S. BRAUER, JOHN C. PEARSON, BRIAN J. DROUIN, SHANSHAN YU, JET PROPULSION LABORATORY, CALIFORNIA INSTITUTE OF TECHNOLOGY, 4800 OAK GROVE DR., PASADENA, CA 91109. a Research described in this paper was performed at the Jet Propulsion Laboratory, California Institute of Technology, under contracts and cooperative agreements with the National Aeronautics and Space Administration. TC08 THE LABORATORY ROTATIONAL SPECTRUM OF SEARCH IN SAGITTARIUS B2(N) 15 min 11:04 -PROPYL CYANIDE AND AN ASTRONOMICAL HOLGER S. P. MÜLLER, I. Physikalisches Institut, Universit ät zu Köln, 50937 K öln; and Max-PlanckInstitut für Radioastronomie, 53121 Bonn, Germany; A. COUTENS, A. WALTERS, CESR, Universit é de Toulouse (UPS), and CNRS, 31028 Toulouse, France; J.-U. GRABOW, Institut f ür Physikalische Chemie und Elektrochemie, Lehrgebiet A, Universit ät Hannover, 30167 Hannover, Germany; A. BELLOCHE, K. M. MENTEN, Max-Planck-Institut f ür Radioastronomie, 53121 Bonn, Germany; S. SCHLEMMER, I. Physikalisches Institut, Universit ät zu Köln, 50937 K öln, Germany. TC09 ROTATIONAL SPECTROSCOPY OF ETHYLAMINE INTO THE THz 15 min 11:21 ZBIGNIEW KISIEL, ADAM KRASNICKI, Institute of Physics, Polish Academy of Sciences, Al. Lotnik ów 32/46, 02-668 Warszawa, Poland; IVAN R. MEDVEDEV, CHRISTOPHER NEESE, SARAH FORTMAN, MANFRED WINNEWISSER, FRANK C. DE LUCIA, Department of Physics, The Ohio State University, Columbus, OH 43210; HOLGER S. P. M ÜLLER, I. Physikalisches Institut, Universit ät zu Köln, Zülpicher Str. 77, 50937 K öln, Germany. TC10 THE SPECTRUM OF METHYL FORMATE IN THE THZ REGION 15 min 11:38 M. TUDORIE, T. R. HUETa , L. MARGULES, M. GOUBET, Laboratoire de Physique des Lasers, Atomes et Molécules (PhLAM) UMR 8523 CNRS, B ât. P5, Université des Sciences et Technologies de Lille 1, 59655 Villeneuve d’Ascq Cedex, France; O. PIRALI, P. ROY, Ligne AILES, synchrotron SOLEIL, LOrme des Merisiers, Saint Aubin, BP 48, 91192 Gif-sur-Yvette, France; V. V. ILYUSHIN, Institute of Radio Astronomy of NASU, Chervonopraporna 4, 61002 Kharkov, Ukraine; I. KLEINER, LISA, CNRS/Universit és Paris 12 et 7, 61 Avenue du Général de Gaulle, 94010 Créteil, France. a This work is supported by the ANR-08-BLAN-0054 contract 22 TC11 15 min PRELIMINARY WORK TO ALMA: SUBMILLIMETER WAVE SPECTROSCOPY OF METHYL FORMATEa O 11:55 AND D SPECIES OF L. MARGULÈS, R. MOTIYENKO, T. R. HUET, Laboratoire PhLAM, CNRS UMR 8523, Universit é de Lille 1, 59655 Villeneuve d’Ascq Cedex, France.; H. MØLLENDAL, Centre for Theoretical and Computational Chemistry (CTCC), University of Oslo, P. O. Box 1033, Blindern, NO-0315 Oslo, Norway; J.C. GUILLEMIN, Sciences Chimiques de Rennes-Ecole Nationale Sup érieure de Chimie de Rennes-CNRS, 35700 Rennes, France; K. DEMYK, Centre d’Etude Spatiale des Rayonnements, Universit é de Toulouse 3, 31028 Toulouse cedex 4, France; M. CARVAJAL, Departamento de F ı̀sica Aplicada, Universidad de Huelva, Spain; I. KLEINER, and L. H. COUDERT, LISA, CNRS UMR 7583, Universit é Paris 12, 94010 Créteil Cedex France. a This work is supported by ANR-08-BLAN-0054 and ANR-08-BLAN-0225 23 TD. MINI-SYMPOSIUM: CAVITY ENHANCED SPECTROSCOPY TUESDAY, JUNE 23, 2009 – 8:30 AM Room: 1015 McPHERSON LAB Chair: KEVIN LEHMANN, University of Virginia, Charlottesville, Virginia TD01 INVITED TALK 30 min 8:30 ANALYSIS OF REACTION MECHANISMS IN FLAMES USING COMBINED CRD- AND LIF-SPECTROSCOPY ANDREAS BROCKHINKE, PATRICK NAU, MARKUS KÖHLER and KATHARINA KOHSEHÖINGHAUS, Physikalische Chemie I, Universit ät Bielefeld, Universitätsstraße 25, D-33615 Bielefeld, Germany. TD02 MID-IR ETHENE DETECTION USING A QUASI-PHASE MATCHED LiNbO WAVEGUIDE 15 min 9:05 ROBERTO GRILLI, School of Chemistry, University of Bristol, Bristol BS8 1TS, U.K.; LUCA CIAFFONI, GRANT A. D. RITCHIE, Department of Chemistry, Physical and Theoretical Chemistry Laboratory, University of Oxford, South Parks Road, Oxford OX1 3QZ, U.K.; and ANDREW J. ORR-EWING, School of Chemistry, University of Bristol, Bristol BS8 1TS, U.K.. TD03 15 min 9:22 MEASUREMENTS OF EXTINCTION BY AEROSOL PARTICLES USING CAVITY RING-DOWN SPECTROSCOPY AND OPTICAL FEEDBACK CAVITY RING-DOWN SPECTROSCOPY DANIEL MELLON, JIN KIM and ANDREW J. ORR-EWING, School of Chemistry, University of Bristol, Bristol BS8 1TS, U.K.. TD04 15 min 9:39 TIME-DEPENDENT EMISSION OF MOLECULAR IODINE FROM BROWN SEAWEED: AN APPLICATION OF INCOHERENT BROADBAND CAVITY-ENHANCED ABSORPTION SPECTROSCOPY SOPHIE DIXNEUFa , ANDY A. RUTH, Laser Spectroscopy Group, Physics Department, University College Cork, Ireland; STEWART VAUGHAN, School of Chemistry, University of Leeds, United Kingdom; RAVI M. VARMA, Laser Spectroscopy Group, Physics Department, University College Cork, Cork, Ireland; and JOHANNES ORPHAL, Laboratoire Inter-universitaire des Syst èmes Atmosphériques, Université Paris XII, Créteil, France. a s.dixneuf@ucc.ie TD05 MEDICAL DIAGNOSTIC BREATH ANALYSIS BY CAVITY RING DOWN SPECTROSCOPY 15 min 9:56 JOSEPH S. GUSS, MARKUS METSÄLÄ and LAURI HALONEN, Laboratory of Physical Chemistry, Department of Chemistry, P.O. Box 55, 00014 University of Helsinki, Finland. Intermission 24 TD06 10 min THE FANTASIO SET-UP (I): DESCRIPTION AND EXTENSION TOWARDS FEMTO-FANTASIO 10:30 K. DIDRICHE, C. LAUZIN, X. DE GHELLINCK, P. MACKO, A. RIZOPOULOS, P. VAN POUCKE, M. HERMAN, Service de Chimie quantique et Photophysique CP160/09, Facult é des Sciences, Université Libre de Bruxelles (U.L.B.), Av. Roosevelt, 50, B-1050, Bruxelles, Belgium; S. KASSI, Laboratoire de Spectrométrie Physique, Laboratoire de Spectromtrie Physique, Universit é Joseph Fourier de Grenoble, B.P. 87, 38402 Saint-Martin-d’Heres Cedex, France. TD07 15 min 10:42 THE FANTASIO SET-UP (II): HIGH RESOLUTION OVERTONE SPECTROSCOPY OF ACETYLENE CONTAINING VAN DER WAALS DIMERS C. LAUZIN, J. DEMAISON, K. DIDRICHE, P. MACKO, J. LIEVIN, M. HERMAN, Service de Chimie quantique et Photophysique CP160/09, Facult é des Sciences, Université Libre de Bruxelles (U.L.B.), Av. Roosevelt, 50, B-1050, Bruxelles, Belgium; A. PERRIN, Laboratoire Interuniversitaire des Syst èmes Atmosphériques (LISA) CNRS-UMR 7583 Université Paris Est et Paris 7, Faculté des Sciences et Technologie, 61, avenue du Général de Gaulle 94010 Créteil Cédex, France; W.J. LAFFERTY, Optical Technology Division, National Institute for Standards and Technology, Gaithersburg, MD 20899-8441, USA. TD08 FIBER-LASER-BASED NICE-OHMS FOR TRACE GAS DETECTION 15 min 10:59 A. FOLTYNOWICZ, W. MA, and O. AXNER, Department of Physics, Ume å University, SE-907 87 Ume å, Sweden. TD09 15 min 11:16 DETERMINATION OF ABSORPTION CROSS SECTIONS OF SURFACE-ADSORBED NITRIC ACID IN THE 290330 NM REGION BY BREWSTER ANGLE CAVITY RING-DOWN SPECTROSCOPY C. ZHU, B. XIANG, R. COLE, AND L. ZHU, Wadsworth Center, New York State Department of Health, and Department of Environmental Health Sciences, State University of New York, Albany, NY 12201. TD10 CAVITY RING DOWN ABSORPTION OF HD AT 90K 15 min 11:33 CARLOS E. MANZANARES and YASNAHIR PEREZ-DELGADO, Department of Chemistry and Biochemistry, Baylor University, Waco, Texas, 76798. 25 TE. RADICALS AND IONS TUESDAY, JUNE 23, 2009 – 8:30 AM Room: 2015 McPHERSON LAB Chair: CARL GOTTLIEB, Harvard Smithsonian Center for Astrophyics, Cambridge, MA TE01 15 min 8:30 THE SPECTRA OF SOLID XENON LUMINESCENCE EXCITED BY THE BULK ELECTRIC DISCHARGE. E. B. GORDON, Institute of Problems of Chemical Physics RAS, Chernogolovka, 142432 Russia; V. D. SIZOV AND V. I. MATYUSHENKO, Institute of Energy Problems of Chemical Physics RAS, Chernogolovka, 142432 Russia. TE02 15 min 8:47 HIGH-RESOLUTION NEAR-INFRARED SPECTROSCOPY OF DEUTERATED CH HAIMING WANG, MARIA KLESHCHEVA, CHRISTOPHER P. MORONG, and TAKESHI OKA, Department of Chemistry, Department of Astronomy Astrophysics, and the Enrico Fermi Institute, University of Chicago, Chicago, IL 60637. TE03 15 min 9:04 CHEMICAL PROBING SPECTROSCOPY OF H IN A CRYOGENIC RADIOFREQUENCY TRAP HOLGER KRECKELa , DENNIS BING, SASCHA REINHARDT, ANNEMIEKE PETRIGNANI, MAX BERG, and ANDREAS WOLF, Max-Planck-Institut f ür Kernpysik, Saupfercheckweg 1, 69117 Heidelberg, Germany. a present address: Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA TE04 15 min 9:21 A CONTINUOUS SUPERSONIC EXPANSION DISCHARGE NOZZLE FOR ROTATIONALLY COLD IONS CARRIE A. KAUFFMAN, KYLE N. CRABTREE, Department of Chemistry, University of Illinois, Urbana, Illinois 61801; BENJAMIN J. MCCALL, Departments of Chemistry and Astronomy, University of Illinois, Urbana, Illinois 61801. TE05 15 min 9:38 PERFORMANCE OF A CONTINUOUS SUPERSONIC EXPANSION DISCHARGE NOZZLE EVALUATED BY LASER-INDUCED FLUORESCENCE SPECTROSCOPY KYLE N. CRABTREE, CARRIE A. KAUFFMAN, Department of Chemistry, University of Illinois, Urbana, IL, 61801; BENJAMIN J. MCCALL, Departments of Chemistry and Astronomy, University of Illinois, Urbana, IL, 61801. TE06 PROGRESS IN THE DEVELOPMENT OF AN INFRARED ION BEAM SPECTROMETER 15 min 9:55 KYLE B. FORD, ANDREW A. MILLS, HOLGER KRECKEL, MANORI PERERA and KYLE N. CRABTREE, Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, IL 61801.; BENJAMIN J. McCALL, Departments of Chemistry and Astronomy, University of Illinois at Urbana-Champaign, Urbana, IL 61801.. 26 TE07 ABSORPTIONS BETWEEN 3000 AND 5500 cm 15 min OF NORMAL AND OXYGEN-18 ENRICHED O 10:12 AND O TRAPPED IN SOLID NEON MARILYN E. JACOX and WARREN E. THOMPSON, Optical Technology Division, National Institute of Standards and Technology, Gaithersburg, MD 20899-8441. Intermission TE08 15 min CORRELATED AB INITIO STUDY OF THE GROUND ELECTRONIC STATE OF THE H –O COMPLEX 10:45 WAFAA M. FAWZY, Department of Chemistry, Murray State University, Murray, KY 42071. TE09 15 min 11:02 MASS-ANALYZED THRESHOLD IONIZATION OF LANTHANUM OXIDE CLUSTERS: La O AND La O LU WU, CHANGHUA ZHANG, SERGIY KRASNOKUTSKI, and DONG-SHENG YANG, Department of Chemistry, University of Kentucky, Lexington, KY 40506-0055. TE10 MICROWAVE DETECTION OF PROTONATED SO IN TWO ISOMERIC FORMS 15 min 11:19 V. LATTANZI, M.C. MCCARTHY, and P. THADDEUS, Harvard-Smithsonian Center for Astrophysics, 60 Garden St., Cambridge, MA 02138, and School of Engineering & Applied Sciences, Harvard University, 29 Oxford St., Cambridge, MA 02138; SVEN THORWIRTH, Max-Planck-Institut f ür Radioastronomie, Auf dem Hügel 69, 53121 Bonn, Germany. TE11 10 min A LABORATORY AND THEORETICAL STUDY OF PROTONATED CARBON DISULFIDE, 11:36 HSCS M. C. MCCARTHY, P. THADDEUS, Harvard-Smithsonian Center for Astrophysics, 60 Garden St., Cambridge, MA 02138, and School of Engineering & Applied Sciences, Harvard University, 29 Oxford St., Cambridge, MA 02138; JEREMIAH J. WILKE AND HENRY F. SCHAEFER III, Center for Computational Chemistry, University of Georgia, 1004 Cedar St, Athens, GA 30602. TE12 INFRARED SPECTROSCOPY AND STRUCTURE OF PROTONATED BENZENE CLUSTERS 15 min 11:48 B. BANDYOPADHYAY, T. CHENG, M. A. DUNCAN, Department of Chemistry, University of Georgia, Athens, GA 30602-2556. 27 TF. RADICALS AND IONS TUESDAY, JUNE 23, 2009 – 1:30 PM Room: 160 MATH ANNEX Chair: HANNA REISLER, University of Southern California, Los Angeles, California TF01 LOW-ENERGY PHOTOELECTRON IMAGING SPECTROSCOPY OF ANIONS 15 min 1:30 CHRISTOPHER L. ADAMS, and J. MATHIAS WEBER, JILA, NIST, and Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309, USA; KENT M. ERVIN, Department of Chemistry, University of Nevada, Reno, 1664 N. Virginia St. MS 216, Reno, NV 89557-0216. TF02 INFRARED SPECTROSCOPY OF HYDRATED NITROMETHANE ANIONS 15 min 1:47 JESSE C. MARCUM, J. MATHIAS WEBER, JILA, NIST, and Department of Chemistry and Biochemistry, University of Colorado, Boulder, CO 80309-0440. TF03 NEGATIVE ION PHOTOELECTRON SPECTRA OF HALOMETHYL ANIONS 15 min 2:04 KRISTEN M. VOGELHUBER, SCOTT W. WREN, JILA, University of Colorado and National Institute of Standards and Technology, and Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309; ANNE B. McCOY, Department of Chemistry, The Ohio State University, Columbus, Ohio 43210; KENT M. ERVIN, Department of Chemistry and Chemical Physics Program, University of Nevada, Reno, Nevada 89557; W. CARL LINEBERGER a , JILA, University of Colorado and National Institute of Standards and Technology, and Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309. a Support from NSF and AFOSR is gratefully acknowledged TF04 NEW ABSORPTION SPECTRA OF CH NEAR 780 NM 15 min 2:21 JU XIN, Department of Physics and Engineering Technology, Bloomsburg University, 400 East Second Street, Bloomsburg PA 17815-1301; ZHONG WANG and TREVOR J. SEARS, Department of Chemistry, Brookhaven National Laboratory, Upton, New York 11973 and Department of Chemistry, Stony Brook University, Stony Brook, New York 11794. TF05 15 min 2:38 FINDING THE ELUSIVE IODOCARBENE: FLUORESCENCE EXCITATION AND SINGLE VIBRONIC LEVEL EMISSION SPECTROSCOPY OF CHI C. TAO, C. EBBEN, H. T. KO AND S. A. REID, Department of Chemistry, Marquette University, Milwaukee, WI 53233; Z. WANG AND T. J. SEARS, Department of Chemistry, Brookhaven National Laboratory, Upton, NY 11973. 28 TF06 15 min 2:55 FINE AND HYPERFINE STRUCTURE IN SUB-DOPPLER, INFRARED, CH-STRETCHING SPECTRA OF MONODEUTERATED METHYL RADICAL MELANIE A. ROBERTS, CHANDRA SAVAGE, FENG DONG, DAVID J. NESBITT, JILA, National Institute of Standards and Technology and University of Colorado, and Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309. TF07 15 min 3:12 HIGH RESOLUTION DIRECT ABSORPTION SPECTROSCOPY OF HYDROXYMETHYL RADICAL IN THE MID-INFRARED MELANIE A. ROBERTS, ERIN N. SHARP-WILLIAMS, DAVID J. NESBITT, JILA, National Institute of Standards and Technology and University of Colorado, and Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309. Intermission TF08 15 min 3:45 IMPROVEMENT OF THE ANALYSIS OF THE PEROXY RADICALS USING AN EVOLUTIONARY ALGORITHM GABRIEL M. P. JUST, PATRICK RUPPER AND TERRY A. MILLER, Department of Chemistry, The Ohio State University, 120 W. 18th Ave., Columbus OH, 43210; W. LEO MEERTS, Molecular and Biophysics group, Institute for Molecules and Materials, Radboud University Nijmegen, P.O. Box 9010, NL-6500 GL Nijmegen, The Netherlands. TF09 15 min 4:02 ANALYSIS OF THE CAVITY RINGDOWN SPECTRA OF THE SMALLEST JET-COOLED ALKYL PEROXY RADICALS USING A EVOLUTIONARY ALGORITHM GABRIEL M. P. JUST, PATRICK RUPPER AND TERRY A. MILLER, Department of Chemistry, The Ohio State University, 120 W. 18th Ave., Columbus OH, 43210; W. LEO MEERTS, Molecular and Biophysics group, Institute for Molecules and Materials, Radboud University Nijmegen, P.O. Box 9010, NL-6500 GL Nijmegen, The Netherlands. TF10 15 min 4:19 HIGH RESOLUTION INFRARED SPECTROSCOPY OF JET-COOLED PHENYL RADICAL IN THE GAS PHASE ERIN N. SHARP-WILLIAMS, MELANIE A. ROBERTS, DAVID J. NESBITT, JILA, National Institute of Standards and Technology and University of Colorado, and Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309. TF11 15 min 4:36 SPECTRUM OF ETHYNYL RADICAL: NEW INSIGHTS INTO THE SPECREINVESTIGATING THE TROSCOPY OF VIBRONIC BANDS ERIN N. SHARP-WILLIAMS, MELANIE A. ROBERTS, DAVID J. NESBITT, JILA, National Institute of Standards and Technology and University of Colorado, and Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309; ROBERT F. CURL, Department of Chemistry and Rice Quantum Institute, Rice University, Houston, Texas 77005. 29 TF12 15 min 4:53 AND ABSORPTIONS OF NO TRAPPED IN SOLID NEON THE MARILYN E. JACOX and WARREN E. THOMPSON, Optical Technology Division, National Institute of Standards and Technology, Gaithersburg, MD 20899-8441. TF13 15 min 5:10 JET-COOLED LASER SPECTROSCOPY OF A JAHN-TELLER AND PSEUDO JAHN-TELLER ACTIVE MOLECULE: THE NITRATE RADICAL MING-WEI CHEN, Laser Spectroscopy Facility, Department of Chemistry, The Ohio State University, 120 W. 18th Avenue, Columbus, Ohio 43210; KANA TAKEMATSU, MITCHIO OKUMURA, Arthor Amos Noyes Laboratory of Chemical Physics, California Institute of Technology, Pasadena, California 91125; and TERRY A. MILLER, Laser Spectroscopy Facility, Department of Chemistry, The Ohio State University, 120 W. 18th Avenue, Columbus, Ohio 43210. TF14 INFRARED VACUUM ULTRAVIOLET SPECTROSCOPY OF ALLYL RADICAL 10 min 5:27 B. REED, C. S. LAM, X. XING, K. C. LAU, C. Y. NG, Department of Chemistry, University of California, Davis, CA 95616; X. ZHANG, Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109; A. VASILIOU, G. B. ELLISON, University of Colorado, Boulder, CO 80309. TF15 15 min 5:39 SPECTROSCOPIC IDENTIFICATION OF p-CHLORO--METHYLBENZYL RADICAL IN THE GAS PHASE SEUNG WOON LEE, GI WOO LEE, SANG KUK LEE, Department of Chemistry and the Chemistry Institute of Functional Materials,Pusan National University, Pusan 609-735, Republic of Korea. 30 TG. INFRARED/RAMAN TUESDAY, JUNE 23, 2009 – 1:30 PM Room: 170 MATH ANNEX Chair: CAROLYN BRAUER, Jet Propulsion Laboratory, Pasadena, California TG01 FOURIER TRANSFORM SPECTROSCOPY WITHOUT MICHELSON INTERFEROMETER 15 min 1:30 J. MANDON, P. JACQUET, M. JACQUEY, G. GUELACHVILI, N. PICQU É, Laboratoire de Photophysique Moléculaire, CNRS, Bâtiment 350, Université Paris-Sud, 91405 Orsay cedex, France; B. BERNHARDT, R. HOLZWARTH, T.W. HÄNSCH, Max Planck Institut für Quantenoptik, Hans-Kopfermann-Str. 1, 85748 Garching, Germany. TG02 15 min 1:47 PRECISION FOURIER TRANSFORM SPECTROSCOPY WITH FEMTOSECOND FREQUENCY COMBS P. JACQUET, J. MANDON, G. GUELACHVILI, N. PICQU É, Laboratoire de Photophysique Mol éculaire, CNRS, Bâtiment 350, Université Paris-Sud, 91405 Orsay cedex, France; B. BERNHARDT, R. HOLZWARTH, T.W. HÄNSCH, Max Planck Institut für Quantenoptik, Hans-Kopfermann-Str. 1, 85748 Garching, Germany. TG03 INFRARED SPECTROSCOPY USING QUANTUM CASCADE LASERS 15 min 2:04 PENG WANG, TOM J. TAGUE , Bruker Optics, Billerica, MA 01821; LAURENT DIEHL, CHRISTIAN PFLÜGL, and FEDERICO CAPASSO, School of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138. TG04 10 min 2:21 THE AILES IR AND THZ HIGH RESOLUTION SPECTROSCOPY BEAMLINE AT SOLEIL : CHARACTERISTICS AND PERFORMANCES PASCALE ROY, JEAN-BLAISE BRUBACH, MATHIEU ROUZIÈRES, MICHEL VERVLOET, OLIVIER PIRALIa , DIDIER BALCON , FRIDOLIN KWABIA-TCHANAb , LAURENT MANCERONc , Synchrotron SOLEIL, L’Orme des Merisiers, Saint-Aubin - BP 48, 91192 Gif-sur-Yvette CEDEX, France. a Laboratoire de Photophysique Moléculaire, Université Paris-Sud, 91405 Orsay Cedex, France Interuniversitaire des Systèmes Atmosphériques, CNRS-Paris 7 and 12, UMR 7583, 61 av. du Général de Gaulle, Créteil France c Lab. Dynamique, Interactions et Réactivité, CNRS-UPMC, UMR 7075, case 49, 4 place Jussieu, 75252 Paris Cedex, France b Lab. TG05 15 min 2:33 FIRST HIGH RESOLUTION ABSORPTION SPECTRA USING THE FAR INFRARED SYNCHROTRON CONTINUUM SOURCE EXTRACTED BY THE “AILES” BEAMLINE AT SOLEIL OLIVIER PIRALIa , PASCALE ROY, JEAN-BLAISE BRUBACH, MATHIEU ROUZIÈRES, DIDIER BALCON , LAURENT MANCERONb and MICHEL VERVLOET, Synchrotron SOLEIL, L’Orme des Merisiers Saint-Aubin, 91192 Gif-sur-Yvette, France. a Laboratoire b Laboratoire de Photophysique Moléculaire, Université Paris-Sud, 91405 Orsay Cedex, France de Dynamique, Interactions et Réactivité, Université Pierre et Marie-Curie, France 31 TG06 THE FAR-INFRARED BEAMLINE AT THE CANADIAN LIGHT SOURCE 10 min 2:50 BRANT BILLINGHURST, TIM MAY, Canadian Light Source Inc. 101 Perimeter Road, Saskatoon SK, S7N 0X4, Canada. TG07 15 min 3:02 THE FAR INFRARED SPECTRUM OF THIOPHOSGENE: ANALYSIS OF THE FUNDAMENTAL BAND AT 500 A.R.W. McKELLAR, Steacie Institute for Molecular Sciences, National Research Council of Canada, Ottawa, ON K1A 0R6, Canada; B.E. BILLINGHURST, Canadian Light Source, 101 Perimeter Road, University of Saskatchewan, Saskatoon, SK S7N 0X4, Canada. TG08 15 min 3:19 MOLECULAR ALIGNMENT EFFECTS IN AMMONIA AT 6.14 m, USING A DOWN-CHIRPED QUANTUM CASCADE LASER SPECTROMETER K. G. HAY, G. DUXBURY and N. LANGFORD, Department of Physics, SUPA, John Anderson Building, University of Strathclyde, 107 Rottenrow, Glasgow G4 0NG, Scotland,UK. Intermission TG09 15 min 3:50 WATER SPECTROSCOPY IN THE 1 m REGION – A CASE STUDY FOR COLLISIONAL NARROWING GEORG WAGNER, MANFRED BIRK, DLR, D 82234 Wessling, Germany. TG10 15 min 4:07 TIME DEPENDENT MEASUREMENTS OF DICKE NARROWING OF A WATER LINE AT 7.84 MICRONS USING A FREQUENCY DOWN-CHIRPED QC LASER SPECTROMETER K. G. HAY, G. DUXBURY and N. LANGFORD, Department of Physics, SUPA, John Anderson Building, University of Strathclyde, 107 Rottenrow, Glasgow G4 0NG, Scotland,UK ; N. TASINATO, Dipartimento di Chimica Fisica, Universita Ca Foscari di Venezia, 30123 Venezia, Italy. TG11 15 min 4:24 HIGH PRECISION MID-IR SPECTROSCOPY OF NEAR 4.3 WEI-JO TING, PEI-LING LUO,CHIEH-HSING CHUNG, Dept. of Physics, National Tsing Hua University, Hsinchu, Taiwan 30013, R.O.C; HSHAN-CHEN CHEN, Inst. of Photonics Technologies, National Tsing Hua University, Hsinchu, Taiwan 30013, R.O.C; YU-HUNG LIEN, and JOW-TSONG SHY, Dept. of Physics, National Tsing Hua University, Hsinchu, Taiwan 30013, R.O.C. 32 TG12 15 min 4:41 OZONE : CRITICAL EVALUATION OF THE STATISTICS OF THE DARK STATE ANALYSES VIA NEW OBSERVATIONS A. BARBE, Groupe de Spectrométrie Moléculaire et Atmosphérique, U.M.R. CNRS 6089, Université de REIMS, Moulin de la Housse, B.P. 1039, 51687 REIMS cedex 2, FRANCE; E. STARIKOVA, LTS, Institute of Atmospheric Optics, 634055 TOMSK, RUSSIA; M.-R. DE BACKER-BARILLY, VL.G. TUYTEREV, ; and Groupe de Spectrométrie Moléculaire et Atmosphérique, U.M.R. CNRS 6089, Université de REIMS, Moulin de la Housse, B.P. 1039, 51687 REIMS cedex 2, FRANCE; A. CAMPARGUE, Groupe de Spectrom étrie Moléculaire et Atmosphérique, U.M.R. CNRS 6089, Université de REIMS, Moulin de la Housse, B.P. 1039, 51687 REIMS cedex 2, FRANCE. TG13 15 min 4:58 REAL TIME IN FLIGHT DETECTION OF METHANE, NITROUS OXIDE, CARBON DIOXIDE AND NITRIC OXIDE USING A CHIRPED QC LASER SPECTROMETER K. G. HAY, G. DUXBURY and N. LANGFORD, Department of Physics, SUPA, John Anderson Building, University of Strathclyde, 107 Rottenrow, Glasgow G4 0NG, Scotland,UK. TG14 10 min 5:15 REAL-TIME ANALYSIS OF RAMAN SPECTRA FOR TEMPERATURE FIELD CHARACTERIZATION IN AIRCRAFT EXHAUST NOISE STUDIES J. WORMHOUDT, D. D. NELSON, K. ANNEN, Aerodyne Research, Inc., Billerica, MA 01821; R. J. LOCKE, ASRC Aerospace Corporation, Cleveland, OH 44135; and M. WERNET, NASA Glenn Research Center, Cleveland, OH 44135. TG15 10 min 5:27 COLLISIONAL EXCITATION OF AUTOMOTIVE FUEL COMPONENTS (ETHANOL AND ISOOCTANE) RACHELLE H. COBB, ALLEN R. WHITE,, Department of Mechanical Engineering, Rose-Hulman Institute of Technology, 5500 Wabash Ave., Terre Haute, IN 47803; REBECCA B. DEVASHER, Department of Chemistry, Rose-Hulman Institute of Technology, 5500 Wabash Ave., Terre Haute, IN 47803. TG16 ANALYSIS OF URINARY CALCULI USING INFRARED SPECTROSCOPIC IMAGING 15 min 5:39 VALDAS SABLINSKAS, DAIVA LESCIUTE, Dept. of General Physics and Spectroscopy, Faculty of Physics, Vilnius University, Sauletekio av. 9 bl. 3, LT-01222, Vilnius, Lithuania. ; VAIVA HENDRIXSON, Dept. of Physiology, Biochemistry and Laboratory Medicine, Faculty of Medicine, Vilnius University, M. K. Ciurlionio str. 21, LT-03101, Vilnius, Lithuania. 33 TH. MINI-SYMPOSIUM: FIR/THz AIR/SPACE MISSIONS TUESDAY, JUNE 23, 2009 – 1:30 PM Room: 1000 McPHERSON LAB Chair: HOLGER MÜLLER, Universität zu Köln, Köln, Germany TH01 INVITED TALK 30 min 1:30 TERAHERTZ SPECTROSCOPY OF MOLECULES IN THE INTERSTELLAR MEDIUM AND AROUND STARS – SURE BETS AND CHALLENGES KARL M. MENTEN, Max-Planck-Institut f ür Radioastronomie, Auf dem H ügel 69, D-53121 Bonn. TH02 15 min 2:05 MOLECULAR SPECTROSCOPY AND THE ATACAMA LARGE MILLIMETER/SUBMILLIMETER ARRAY (ALMA) ANTHONY J. REMIJAN, NORTH AMERICAN ALMA SCIENCE CENTER (NAASC), National Radio Astronomy Observatory, 520 Edgemont Road, Charlottesville, VA 22903. TH03 THE HERSCHEL SPACE OBSERVATORY, OPENING THE FAR INFRARED 15 min 2:22 JOHN C. PEARSON, JET PROPULSION LABORATORY, CALIFORNIA INSTITUTE OF TECHNOLOGY, 4800 OAK GROVE DR., PASADENA, CA 91109. TH04 THE STRATOSPHERIC OBSERVATORY FOR INFRARED ASTRONOMY (SOFIA) 15 min 2:39 R. D. GEHRZ, Department of Astronomy, University of Minnesota, 116 Church Street, S. E., Minneapolis, MN 55455; E. E. BECKLIN, Universities Space Research Association, NASA Ames Research Center, MS 211-3, Moffett Field, CA 94035. TH05 15 min 2:56 INFRARED SPECTROSCOPY OF ASTROPHYSICAL GAS, GRAINS, AND ICES WITH THE STRATOSPHERIC OBSERVATORY FOR INFRARED ASTRONOMY (SOFIA) R. D. GEHRZ, Department of Astronomy, University of Minnesota, 116 Church Street, S. E., Minneapolis, MN 55455; E. E. BECKLIN, Universities Space Research Association, NASA Ames Research Center, MS 211-3, Moffett Field, CA 94035. TH06 15 min 3:13 TERAHERTZ SPECTROSCOPY AND GLOBAL ANALYSIS OF H O SHANSHAN YU, BRIAN J. DROUIN, JOHN C. PEARSON AND HERBERT M. PICKETT, Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109. 34 TH07 15 min 3:30 ACCURATE POTENTIAL ENERGY SURFACE, ROVIBRATIONAL ENERGY LEVELS, AND TRANSITIONS OF AMMONIA ISOTOPOLOGUES: NH , NH , ND and NT XINCHUAN HUANG, MS 245-6, NASA Ames Research Center, Moffett Field, CA, 94035; DAVID W. SCHWENKE, MS T27B-1, NASA Ames Research Center, Moffett Field, CA, 94035; TIMOTHY J. LEE, MS 245-1, NASA Ames Research Center, Moffett Field, CA, 94035. Intermission TH08 15 min 4:00 MEASUREMENT AND ANALYSIS OF ATMOSPHERICALLY BROADENED LINEWIDTHS AND LINESHAPES IN THE MILLIMETER SPECTRAL REGION COREY CASTO and FRANK C. DE LUCIA, Department of Physics, The Ohio State University, Columbus, OH 43210-1106. TH09 15 min 4:17 PRESSURE BROADENING OF SEVERAL TERAHERTZ TRANSITIONS OF WATER FROM 20K TO 200K MICHAEL J. DICK, BRIAN J. DROUIN and JOHN C. PEARSON, Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California 91109. TH10 ASSIGNMENT AND ANALYSIS OF LOW-BARRIER ASYMMETRIC TOPS WITH SPFIT/SPCAT 15 min 4:34 BRIAN J. DROUIN, JOHN C. PEARSON, Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109-8099. TH11 MILLIMETER WAVE AND TERAHERTZ SPECTRA OF C-13 METHANOL 15 min 4:51 LI-HONG XU, RONALD M. LEES, Department of Physics and Centre for Laser, Atomic, and Molecular Sciences, University of New Brunswick, Saint John, NB E2L 4L5, Canada; HOLGER S. P. M ÜLLER, CHRISTIAN P. ENDRES, FRANK LEWEN, STEPHAN SCHLEMMER, I. Physikalisches Institut, Universitt zu Köln, 50937 K öln, Germany; KARL M. MENTEN, Max-Planck-Institut f ür Radioastronomie, 53121 Bonn, Germany. TH12 15 min 5:08 GAS CELL OBSERVATIONS OF METHANOL FROM 0.6 TO 1.9 THZ USING THE HERSCHEL SPACE OBSERVATORY HIFI INSTRUMENT RONAN D. HIGGINS, Department of Experimental Physics, National University of Ireland, Maynooth, Co. Kildare, Ireland; JOHN C. PEARSON, Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA; STEVE D. LORD, NHSC, California Institute of Technology, Pasadena, CA 91125, USA; DAVID TEYSSIER, Herschel Science Centre, European Space Astronomy Centre (ESAC), 28691 Villanueva de la Ca ñada, Madrid, Spain. TH13 THE SUBMILLIMETER SPECTRUM OF THE GROUND TORSIONAL STATE OF CH DOH 15 min 5:25 JOHN C. PEARSON, CAROLYN S. BRAUER, SHANSHAN YU, and BRIAN J. DROUIN, JET PROPULSION LABORATORY, CALIFORNIA INSTITUTE OF TECHNOLOGY, 4800 OAK GROVE DR., PASADENA, CA 91109. 35 TI. ATMOSPHERIC SPECIES TUESDAY, JUNE 23, 2009 – 1:30 PM Room: 1015 McPHERSON LAB Chair: MARK MARSHALL, Amherst College, Amherst, Massachusetts TI01 15 min 1:30 ABSORPTION SPECTRUM OF 2-NITROOXYBUTYL PEROXY RADICAL The NATHAN EDDINGSAAS, KANA TAKEMATSU, and MITCHIO OKUMURA, Arthur Amos Noyes Laboratory of Chemical Physics, California Institute of Technology, Pasadena, California 91125. TI02 THE DISSOCIATION ENERGY OF THE HOOO RADICAL 15 min 1:47 M.E. VARNER, J. VÁZQUEZ, M.E. HARDING, J.F. STANTON, Department of Chemistry, The University of Texas at Austin, TX; J. GAUSS, Institut f ür Physikalische Chemie, Universität Mainz, Germany. TI03 15 min 2:04 INFRARED ABSORPTION OF GASEOUS -CLCOOH AND -CLCOOH RECORDED WITH A STEP-SCAN FOURIER-TRANSFORM SPECTROMETER YUAN-PERN LEE AND LI-KANG CHU, Department of Applied Chemistry and Institute of Molecular Science, National Chiao Tung University, Hsinchu 30010, Taiwan and Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 10617, Taiwan. TI04 ANALYSIS OF THE BAND OF THE FCO RADICAL: PRELIMINARY RESULTS 15 min 2:21 A. PERRIN, Laboratoire Inter Universitaire des Systemes Atmosph ériques, CNRS, Universités Paris 12 et 7, 61 Av du Général de Gaulle, 94010 Créteil Cedex France; M. STŘIŽÍK, VŠB-Technical University of Ostrava, Faculty of Safety Engineering, Lumı́rova 13, CZ-70030, Ostrava 3 - V ýškovice, Czech Republic, Institute of Thermomechanics, v.v.i., Academy of Sciences of the Czech Republic, Dolejškova 5, CZ-18200 Prague 8, Czech Republic; H. BECKERS, H. WILLNER, Inorg. Chemistry, University of Wuppertal, D-42119 Wuppertal, GERMANY; Z.ZELINGER, P.PRACNA, J. Heyrovský Institute of Physical Chemistry, Academy of Sciences of the Czech Republic, Dolejškova 3, CZ-18223 Prague 8, Czech Republic; V. NEVRL Ý, E. GRIGOROVÁ, VŠB-Technical University of Ostrava, Faculty of Safety Engineering, Lumı́rova 13, CZ-70030, Ostrava 3 - Výškovice, Czech Republic, Institute of Thermomechanics, v.v.i, Academy of Sciences of the Czech Republic, Dolejškova 5, CZ-18200 Prague 8, Czech Republic.. TI05 15 min 2:38 CONFORMATIONAL ANALYSIS OF 1-ALKENE SECONDARY OZONIDES BY MEANS OF MATRIX ISOLATION FTIR SPECTROSCOPY VALDAS SABLINSKAS, SIMONA STRAZDAITE, JUSTINAS CEPONKUS, Dept. of General Physics and Spectroscopy, Faculty of Physics, Vilnius University, Sauletekio av. 9 bl. 3, LT-01222, Vilnius, Lithuania. Intermission 36 TI06 15 min 3:15 TEMPERATURE DEPENDENCE OF THE VIBRATIONAL RELAXATION OF OH( = 1, 2) BY O, O , AND CO C. ROMANESCU, H. TIMMERS, K. S. KALOGERAKIS, G. P. SMITH, and R. A. COPELAND, SRI International, Molecular Physics Laboratory, 333 Ravenswood Ave., Menlo Park, CA 94025. TI07 15 min 3:32 EXPERIMENTAL AND THEORETICAL INVESTIGATIONS OF HBr+He ROTATIONAL ENERGY TRANSFER M. H. KABIR, I. O. ANTONOV, J. M. MERRITT, and M. C. HEAVEN, Department of Chemistry, Emory University, Atlanta, GA 30322. TI08 15 min 3:49 THE ATMOSPHERIC CHEMISTRY EXPERIMENT, ACE: ORGANIC MOLECULES FROM ORBIT J. J. HARRISON, G. GONZALEZ ABAD, N. ALLEN, P. F. BERNATH, Department of Chemistry, University of York, Heslington, York, YO10 5DD, UK; and C. BOONE, Department of Chemistry, University of Waterloo, Waterloo, ON, N2L 3G1, Canada. TI09 GLOBAL METHYL CHLORIDE MEASUREMENTS FROM THE ACE-FTS INSTRUMENT 15 min 4:06 NATALIE WEIGUM, CLARE McELCHERAN, KALEY A. WALKER, JEFFREY R. TAYLOR, Department of Physics, University of Toronto, Toronto, Ontario, Canada M5S 1A7; CHRIS BOONE, PETER F. BERNATH, Department of Chemistry, University of Waterloo, Waterloo, Ontario, Canada N2L 3G1; GEOFFREY C. TOON, GLORIA MANNEY, Jet Propulsion Laboratory, Pasadena, CA 91109, USA; SUSAN STRAHAN, BRYAN DUNCAN, YASUKO YOSHIDA, Goddard Earth Science and Technology Center, University of Maryland, Baltimore County, Baltimore, MD 21250, USA; and YUAHNG WANG, School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, GA USA. TI10 15 min 4:23 ABSOLUTE CHEMICAL ANALYSIS OF COMPLEX MIXTURES IN THE SUBMILLIMETER/TERAHERTZ. CHRISTOPHER F. NEESE, IVAN R. MEDVEDEV AND FRANK C. DE LUCIA, Department of Physics, 191 W. Woodruff Ave., Ohio State University, Columbus, OH 43210 USA; GRANT M. PLUMMER, Enthalpy Analytical, Inc., 2202 Ellis Rd., Durham, NC 27703 USA. TI11 SUB-MILLIMETER/THZ SPECTROSCOPY AT THE CONGESTION LIMIT 15 min 4:40 DAVID L. GRAFF, CHRISTOPHER F. NEESE, IVAN R. MEDVEDEV AND FRANK C. DE LUCIA, The Ohio State University, Department of Physics, Columbus, Ohio 43210. TI12 15 min 4:57 THE WATER-VAPOR CONTINUUM ABSORPTION IN THE MID-INFRARED WINDOWS AT TEMPERATURES FROM 311 K TO 363 K Yu. I. BARANOV, AND W. J. LAFFERTY, Optical Technology Division, NIST, Gaithersburg, MD 208998441, USA. 37 TJ. ELECTRONIC TUESDAY, JUNE 23, 2009 – 1:30 PM Room: 2015 McPHERSON LAB Chair: DENNIS CLOUTHIER, University of Kentucky, Lexington, Kentucky TJ01 15 min 1:30 HIGH-RESOLUTION SPECTROSCOPY OF p RYDBERG STATES OF He : 1. RYDBERG-STATE-RESOLVED THRESHOLD IONIZATION SPECTRA OF METASTABLE He JINJUN LIU, DANIEL SPRECHER, MATTHIAS RAUNHARDT, MARTIN SCH ÄFER, and FRÉDÉRIC MERKT, ETH Zürich, Laboratorium f ür Physikalische Chemie, Wolfgang-Pauli-Strasse 10, 8093 Z ürich, Switzerland. TJ02 15 min 1:47 HIGH-RESOLUTION SPECTROSCOPY OF p RYDBERG STATES OF He : 2. AUTOIONIZATION DYNAMICS AND MQDT CALCULATIONS MARTIN SCHÄFER, MATTHIAS RAUNHARDT, DANIEL SPRECHER, JINJUN LIU, and FR ÉDÉRIC MERKT, ETH Zürich, Laboratorium f ür Physikalische Chemie, Wolfgang-Pauli-Strasse 10, 8093 Z ürich, Switzerland. TJ03 OBSERVATION OF A LINEAR ISOMER OF THE C -Xe VAN DER WAALS COMPLEX 15 min 2:04 KENG SENG THAM, JUN-MEI CHAO, GUIQIU ZHANG, ANTHONY J. MERER, YEN-CHU HSU, Institute of Atomic and Molecular Sciences, Academia Sinica, P. O. Box 23-166, Taipei 10617, R. O. C.; WEI-PING HU, Department of Chemistry, National Chung-Cheng University, Taiwan, R. O. C. TJ04 15 min 2:21 THE ELECTRONIC SPECTRUM AND MOLECULAR STRUCTURE OF THE ARSENYL (H As=O) FREE RADICAL SHENG-GUI HE, Institute of Chemistry, Chinese Academy of Sciences, Zhongguancun, Beijing 100080, P.R.C.; FUMIE X. SUNAHORI, JIE YANG, AND DENNIS J. CLOUTHIER, Department of Chemistry, University of Kentucky, Lexington, KY 40506-0055. TJ05 DISCOVERY OF THE ELECTRONIC SPECTRA OF HPS AND DPS 10 min 2:38 ROBERT A. GRIMMINGER, JIE WEI, BLAINE ELLIS and DENNIS J. CLOUTHIER, Department of Chemistry, University of Kentucky, Lexington, KY, 40506; ZHONG WANG and TREVOR SEARS, Department of Chemistry, Brookhaven National Lab, Upton, NY 11973. TJ06 15 min 2:50 THE ELECTRONIC SPECTRA OF THE JET-COOLED BORON DIFLUORIDE (BF ) AND BORON DICHLORIDE (BCl ) FREE RADICALS JIE YANG, JIE WEI, FUMIE SUNAHORI, MOHAMMED GHARAIBEH, BLAINE ELLIS, ALFRED CHEN, and DENNIS J. CLOUTHIER, Department of Chemistry, University of Kentucky, Lexington, KY 40506-0055, USA; SHENG-GUI HE, Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, The Chinese Academy of Sciences, Zhongguancun, Beijing 100080, PRC. 38 TJ07 ULTRAHIGH-RESOLUTION SPECTROSCOPY OF THE 15 min 3:07 TRANSITION OF NO RADICAL SHUNJI KASAHARA, KENICHIROU KANZAWA, YOSUKE SEMBA, KAZUTO YOSHIDA, Molecular Photoscience Research Center, Kobe University, Kobe 657-8501, Japan; MASAAKI BABA, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan; TAKASHI ISHIWATA, Faculty of Information Sciences, Hiroshima City University, Hiroshima 731-3194, Japan; EIZI HIROTA, The Graduate University for Advanced Studies, Kanagawa 240-0193, Japan. TJ08 15 min 3:24 - ABSORPTION SPECTRA OF CYCLOPENTYL AND CYCLOHEXYL PEROXY OBSERVATION OF THE RADICALS BY CAVITY RINGDOWN SPECTROSCOPY PHILLIP S. THOMAS, RABI CHHANTYAL-PUN, AND TERRY A. MILLER, Laser Spectroscopy Facility, Department of Chemistry, The Ohio State University, 120 W. 18th Avenue, Columbus OH 43210. Intermission TJ09 THE GAS-PHASE SPECTRA OF THE 1-INDANYL RADICAL 15 min 4:00 TYLER P. TROY, MASAKAZU NAKAJIMA, NAHID CHALYAVI, RAPHA ËL G. C. R. CLADY, KLAAS NAUTA, SCOTT H. KABLE, and TIMOTHY W. SCHMIDT, School of Chemistry, The University of Sydney, NSW 2006, AUSTRALIA. TJ10 SPATIALLY SEPARATING STRUCTURAL ISOMERS OF NEUTRAL MOLECULES 15 min 4:17 FRANK FILSINGER, JOCHEN KÜPPER, GERARD MEIJER, Fritz-Haber-Institut der Max-PlanckGesellschaft, Faradayweg 4-6, 14195 Berlin, Germany; JONAS L. HANSEN, LOTTE HOLMEGAARD, JENS H. NIELSEN, IFTACH NEVO, JOCHEN MAURER, and HENRIK STAPELFELDT, Department of Chemistry, University of Aarhus, DK-8000 Aarhus C, Denmark. TJ11 15 min 4:34 SLOW ELECTRON VELOCITY MAPPING FOR THE STUDY OF CATIONIC STATES OF AROMATIC MOLECULES CHIH-HSUAN CHANG, Department of Chemistry, Brookhaven National Laboratory, Upton, New York 11973; GARY V. LOPEZ and PHILIP M. JOHNSON, Department of Chemistry, Stony Brook University, Stony Brook, New York 11794; TREVOR J. SEARS, Department of Chemistry, Brookhaven National Laboratory, Upton, New York 11973 and Department of Chemistry, Stony Brook University, Stony Brook, New York 11794. TJ12 15 min 4:51 IONIZATION ENERGY MEASUREMENTS AND SPECTROSCOPY OF HfO AND HfO J. M. MERRITT, V. E. BONDYBEY, and M. C. HEAVEN, Department of Chemistry, Emory University, Atlanta, GA 30322. 39 TJ13 15 min 5:08 HIGH RESOLUTION ELECTRONIC SPECTROSCOPY OF THE ARGON VAN DER WAALS COMPLEXES OF 1, 2, 3, 6, 7, 8-HEXAHYDROPYRENE IN THE GAS PHASE. a PHILIP J. MORGAN, ADAM J. FLEISHER, JOSEPH R. ROSCIOLI b and DAVID W. PRATT, Department of Chemistry, University of Pittsburgh, PA 15260. a Work supported by NSF (CHE-0615755) address: JILA, National Institute of Standards and Technology and University of Colorado, and Department of Chemistry and Biochemistry, University of Colorado, Boulder, CO 80309. b Present TJ14 15 min 5:25 NONRADIATIVE DECAY PATHWAYS OF THE FIRST EXCITED ELECTRONIC STATES OF 1:1 HYDROGEN BONDED COMPLEXES OF 7-AZAINDOLE WITH PHENOL AND FORMAMIDE MOITRAYEE MUKHERJEE, ANAMIKA MUKHOPADHYAY AND TAPAS CHAKRABORTY, Physical Chemistry Department, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700032. TJ15 15 min 5:42 HYDROGEN BONDING EFFECTS ON NONRADIATIVE CHANNELS OF INDOLE BY APROTIC POLAR SOLVENTS MOITRAYEE MUKHERJEE, TAPAS CHAKRABORTY, Physical Chemistry Department, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700032. 40 WA. PLENARY SESSION WEDNESDAY, JUNE 24, 2009 – 8:30 AM Room: AUDITORIUM, INDEPENDENCE HALL Chair: MALCOLM CHISHOLM, The Ohio State University, Columbus, Ohio WA01 POTENTIOLOGYa IN SPECTROSCOPY: IT MATTERS 40 min 8:30 ROBERT J. LE ROY, Guelph-Waterloo Centre for Graduate Work in Chemistry and Biochemistry, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada. a potentiology (noun): study focusing on the development of new interatomic pair potential forms; sometimes pursued in an obsessive compulsive manner [The New Yorel Dictionary (2002, unpublished)]. WA02 40 min 9:15 STRUCTURE AND RADIATIONLESS TRANSITION OF PAHS : ULTRAHIGH-RESOLUTION SPECTROSCOPY AND AB INITIO CALCULATION MASAAKI BABA, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan. Intermission WA03 40 min 10:20 HALOGEN BONDS AND HYDROGEN BONDS IN THE GAS PHASE: SIMILARITY REVEALED THROUGH ROTATIONAL SPECTROSCOPY. A. C. LEGON, School of Chemistry, University of Bristol, Bristol, BS8 1TS, U.K.. WA04 IMAGING PAIR-CORRELATED PREDISSOCIATION OF HYDROGEN-BONDED DIMERS 40 min 11:05 HANNA REISLER, Department of Chemistry, University of Southern California, Los Angeles, CA 900890482. 41 WF. DYNAMICS WEDNESDAY, JUNE 24, 2009 – 1:30 PM Room: 160 MATH ANNEX Chair: FLEMING CRIM, University of Wisconsin, Madison, Wisconsin WF01 STUDIES OF THE PREDISSOCIATED, QUASILINEAR OPTICAL DOUBLE RESONANCE SPECTROSCOPY B 15 min 1:30 STATE OF CH Cl AND CD Cl BY OPTICAL- C. TAO, C. MUKARAKATE AND S. A. REID, Department of Chemistry, Marquette University, Milwaukee, WI 53233. WF02 PHOTOFRAGMENTATION DYNAMICS OF 15 min 1:47 JOSHUA P. MARTIN, JOSHUA P. DARR, W. CARL LINEBERGER, JILA and Department of Chemistry and Biochemistry, University of Colorado, Boulder, CO 80309; ANNE B. MCCOY, Department of Chemistry, The Ohio State University, Columbus, OH 43210. WF03 15 min 2:04 DISSOCIATION DYNAMICS OF THE IBr (CO ) VAN DER WAALS CLUSTER: A DIRECT VIEW OF SOLVENTDRIVEN NON-ADIABATIC TRANSITIONS LEONID SHEPS, ELISA M. MILLER, ROBERT PARSON, and W. CARL LINEBERGER a , JILA, Department of Chemistry and Biochemistry, University of Colorado at Boulder, Boulder, CO 80309; MATTHEW A. THOMPSON, US Naval Research Lab, Washington, DC 20375; SAMANTHA HORVATH and ANNE B. McCOY, Department of Chemistry, The Ohio State University, Columbus, OH 43210. a We gratefully acknowledge the funding from NSF and AFOSR WF04 15 min 2:21 ULTRAFAST STUDY OF BROMINE RADICAL IN SOLUTION: THE ROLE OF COMPLEXES AND VIBRATIONAL EXCITATION STACEY L. CARRIER, THOMAS J. PRESTON, ANDREW C. CROWTHER, F. FLEMING CRIM, The University of Wisconsin - Madison Department of Chemistry, 1101 University Avenue, Madison, WI 53705. WF05 15 min 2:38 LASER-INDUCED ALIGNMENT AND ORIENTATION OF QUANTUM-STATE-SELECTED LARGE MOLECULES FRANK FILSINGER, JOCHEN KÜPPER, GERARD MEIJER, Fritz-Haber-Institut der Max-PlanckGesellschaft, Faradayweg 4-6, 14195 Berlin, Germany; LOTTE HOLMEGAARD, JENS H. NIELSEN, IFTACH NEVO, JONAS L. HANSEN, and HENRIK STAPELFELDT, Department of Chemistry, University of Aarhus, DK-8000 Aarhus C, Denmark. Intermission 42 WF06 THE QUANTITATIVE ANALYSIS OF THE ROTATIONAL SPECTRUM OF NCNCS 15 min 3:15 MANFRED WINNEWISSER, BRENDA P. WINNEWISSER, IVAN R. MEDVEDEV, and FRANK C. DE LUCIA, Department of Physics, The Ohio State University, Columbus Ohio, 432101106; STEPHEN C. ROSS, Department of Physics and Centre for Laser, Atomic, and Molecular Sciences, University of New Brunswick, P.O. Box 4400, Fredericton NB E3B 5A3, Canada; and JACEK KOPUT, Department of Chemistry, Adam Mickiewicz University, 60-780 Poznan, Poland. WF07 15 min 3:32 ANOMALOUS CENTRIFUGAL DISTORTION AND A GENERALIZED DEFINITION OF A QUASILINEAR MOLECULE MANFRED WINNEWISSER, IVAN R. MEDVEDEV, and BRENDA P. WINNEWISSER, FRANK C. DE LUCIA, Department of Physics, The Ohio State University, Columbus Ohio, 432101106; JACEK KOPUT, Department of Chemistry, Adam Mickiewicz University, 60-780 Poznan, Poland; and STEPHEN C. ROSS, Department of Physics and Centre for Laser, Atomic, and Molecular Sciences, University of New Brunswick, P.O. Box 4400, Fredericton NB E3B 5A3, Canada. WF08 15 min 3:49 REACTION DYNAMICS OF VIBRATIONALLY EXCITED CH D MOLECULES WITH CHLORINE CHRISTOPHER J. ANNESLEY, ANDREW E. BERKE, F. FLEMING CRIM, The University of Wisconsin Madison Department of Chemistry, 1101 University Avenue, Madison, WI 53705. WF09 15 min 4:06 THE Cl+H HCl+H REACTION INDUCED BY IRRADIATION OF Cl IN SOLID PARAHYDROGEN SHARON C. KETTWICH and DAVID T. ANDERSON, Department of Chemistry, University of Wyoming, Laramie, WY 82071-3838, USA; PAUL L. RASTON, Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada. WF10 15 min 4:23 THEORETICAL STUDIES OF THE ROLE OF VIBRATIONAL EXCITATION ON THE DYNAMICS OF THE HYDROGEN-TRANSFER REACTION OF F( P) + HCl FH + Cl( P) SARA E. RAY, GÉ W. M. VISSERS and ANNE B. McCOY, Department of Chemistry, The Ohio State University, Columbus, OH 43210. WF11 PROBING THE REACTION PATH OF 15 min 4:40 CH + H CH CH + H AND ISOTOPOLOGUES CHARLOTTE E. HINKLE, ANNE B. McCOY, Department of Chemistry, The Ohio State University, Columbus, OH 43210. WF12 INTRAMOLECULAR VIBRATIONAL ENERGY REDISTRIBUTION IN THE REACTION H + CO H + HCO /HOC 15 min 4:57 TSUNEO HIRANO, Department of Chemistry, Faculty of Science, Ochanomizu University, Tokyo 112-8610, Japan; HUI LI, ROBERT J. LE ROY, and TAKAYOSHI AMANO, Department of Chemistry, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada. 43 WF13 15 min 5:14 MEASUREMENT OF THE VIBRATIONAL POPULATION DISTRIBUTION OF BARIUM SULFIDE SEEDED IN AN ARGON SUPERSONIC EXPANSION FOLLOWING PRODUCTION THROUGH THE REACTION OF LASER ABLATED BARIUM WITH CARBONYL SULFIDE CHRIS T. DEWBERRY, GARRY S. GRUBBS II, KERRY C. ETCHISON, and STEPHEN A. COOKE, The Department of Chemistry, University of North Texas, P.O. Box 305070, Denton, TX, 76203-5070. WF14 DC SLICED PHOTODISSOCIATION STUDY OF OZONE AT 226NM 10 min 5:31 PRASHANT. CHANDRA. SINGH, L. SHEN, A. G. SUITS, Department of Chemistry, Wayne State University, Detroit, MI 48201; G. C. MCBANE, Grand Valley State University, Allendale, MI 49401; R. SCHINKE, Max Planck Institute for Dynamics and Self-organization, D-37073 Gottingen, Germany. 44 WG. INFRARED/RAMAN WEDNESDAY, JUNE 24, 2009 – 1:30 PM Room: 170 MATH ANNEX Chair: ROBERT McKELLAR, National Research Council of Canada, Ottawa, ON, Canada WG01 STATUS ON THE GLOBAL VIBRATION-ROTATION MODEL IN ACETYLENE 15 min 1:30 B. AMYAY, M. HERMAN, Service de Chimie quantique et Photophysique CP160/09, Facult é des Sciences, Université Libre de Bruxelles (U.L.B.), Av. Roosevelt, 50, B-1050, Bruxelles, Belgium; A. FAYT, Laboratoire de Spectroscopie Moléculaire, Université Catholique de Louvain, Chemin du Cyclotron, 2, B-1348 LouvainLa-Neuve, Belgium. WG02 15 min 1:47 EXPLORING THE VIBRATIONAL STRUCTURE OF THE VINYLIDENE ANION USING ARGON PREDISSOCIATION SPECTROSCOPY KRISTIN J. BREEN, HELEN K. GERARDI, GEORGE H. GARDENIER, TIMOTHY L. GUASCO, JENNIFER E. LAASER, ERIC G. DIKEN, GARY H. WEDDLE and MARK A. JOHNSON, Sterling Chemistry Laboratory, Yale Universtiy, PO Box 208107, New Haven, CT 06520. WG03 15 min 2:04 UNRAVELLING THE MECHANISM OF RESONANT TWO-PHOTON PHOTODETACHMENT OF THE VINYLIDENE ANION, H C=C , USING VELOCITY-MAP PHOTOELECTRON IMAGING H. K. GERARDI, K. J. BREEN, G. H. GARDENIER, T. L. GUASCO, J. E. LAASER, G. H. WEDDLE, and M. A. JOHNSON, Sterling Chemistry Laboratory, Yale University, PO Box 208107, New Haven, CT 06520. WG04 15 min 2:21 DETECTION AND ANALYSIS OF ROTATIONALLY RESOLVED TORSIONAL SPLITTINGS IN PHENOL (C H OH): THE HIGH RESOLUTION FTIR SPECTRUM OF PHENOL BETWEEN 600 AND 1300 CM SIEGHARD ALBERT, MARTIN QUACK, PHYSICAL CHEMISTRY, ETH Z ÜRICH, CH-8093 ZÜRICH, SWITZERLAND. WG05 15 min 2:38 SH-STRETCHING INTENSITIES AND INTRAMOLECULAR HYDROGEN BONDING IN ALKANETHIOLS B. J. MILLER, J. R. LANE, A. H. SODERGREN, H. G. KJAERGAARD, Department of Chemistry, University of Otago, P.O. Box 56, Dunedin, New Zealand; M. E. DUNN, AND V. VAIDA, Department of Chemistry and Biochemistry and CIRES, University of Colorado, Campus Box 215, Boulder, CO 80309. WG06 10 min 2:55 INVESTIGATION OF MEMBRANE PEPTIDES BY TWO-DIMENSIONAL INFRARED SPECTROSCOPY EMILY ANN BLANCO, MARTIN T. ZANNI, Department of Chemistry, University of Wisconsin Madison, 1101 University Ave, Madison, WI 53706. 45 WG07 15 min 3:07 GAS PHASE RAMAN SPECTRA OF BUTADIENE AND BUTADIENE-d AND THE INTERNAL ROTATION POTENTIAL ENERGY FUNCTION PRAVEENKUMAR BOOPALACHANDRAN, JAAN LAANE, Dept. of Chemistry, Texas A&M University, College Station, TX 77843-3255; and NORMAN C. CRAIG, Dept. of Chemistry & Biochemistry, Oberlin College, Oberlin, OH 44074. WG08 10 min 3:24 SECONDARY PERIODICITY IN THE STRUCTURAL AND VIBRATIONAL CHARACTERISTICS OF 3,3DIMETHYLCYCLOPROPENES DI- AND MONOSUBSTITUTED BY –X (X = C, Si, Ge, Sn, Pb) Yu. N. PANCHENKO, A. V. ABRAMENKOV, Div. of Phys. Chem., Dept. of Chem., M. V. Lomonosov Moscow State University, Moscow 119992, Russian Federation; and G. R. DE MAR É, Université Libre de Bruxelles, Faculté des Sciences, Service de Chimie Quantique et de Photophysique, CP160/09, 50 av. F. D. Roosevelt, B1050 Brussels, Belgium. Intermission WG09 15 min 3:50 DENSITY FUNCTIONAL THEORY STUDY ON MOLECULAR STRUCTURE AND VIBRATIONAL SPECTRA OF 4-AMINO-1-METHYLBENZENE M. KUMRU, T. BARDAKCI, L. SARI, Fatih University, Faculty of Arts and Sciences, Department of Physics, 34500 Bykekmece, Istanbul, TURKEY. WG10 15 min 4:07 THE r STRUCTURAL PARAMETERS OF EQUATORIAL BROMOCYCLOBUTANE, CONFORMATIONAL STABILITY FROM TEMPERATURE DEPENDENT INFRARED SPECTRA OF XENON SOLUTIONS, AND VIBRATIONAL ASSIGNMENTS ARINDAM GANGULY, JOSHUA J. KLAASSEN, TODOR K. GOUNEV, JAMES R. DURIG, DEPARTMENT OF CHEMISTRY, UNIVERSITY OF MISSOURI-KANSAS CITY, KANSAS CITY, MO 64110,USA; GAMIL A. GUIRGIS, DEPARTMENT OF CHEMISTRY AND BIOCHEMISTRY, COLLEGE OF CHARLESTON, CHARLESTON, SC 29424, USA. WG11 15 min 4:24 MEASUREMENT OF ROTATIONAL STATE-TO-STATE RELAXATION COEFFICIENTS BY RAMAN-RAMAN DOUBLE RESONANCE. APPLICATION TO SELF-COLLISIONS IN ACETYLENE. J. L. DOMENECH, R. Z. MARTINEZ, and D. BERMEJO, Instituto de Estructura de la Materia (CSIC), Serrano 123, E-28006 Madrid, SPAIN. WG12 RAMAN SPECTRAL SIGNATURES AS CONFORMATIONAL PROBES OF BIOMOLECULES 10 min 4:41 AMIR GOLAN, NITZAN MAYORKAS, SALMAN ROSENWAKS, ILANA BAR, Department of Physics, Ben-Gurion University, Beer Sheva 84105, Israel. 46 WG13 15 min 4:53 CONFORMATION-SPECIFIC AND MASS-RESOLVED, INFRARED-POPULATION TRANSFER SPECTROSCOPY OF THE MODEL -PEPTIDE Ac- -hPhe-NHMe: EVIDENCE FOR THE PRESENCE OF INTRAMOLECULAR AMIDE-AMIDE STACKING INTERACTIONS. WILLIAM H. JAMES III, EVAN G. BUCHANAN, CHRISTIAN W. M ÜLLER , and TIMOTHY S. ZWIER, Department of Chemistry, Purdue University, West Lafayette, IN 47907; MICHAEL G. D. NIX, School of Chemistry, University of Bristol, Bristol BS8 1TS, UK; LI GUO, and SAMUEL H. GELLMAN, Department of Chemistry, University of Wisconsin-Madison, Madison, WI 53706. WG14 15 min 5:10 CALCULATION OF THE MOLAR VOLUME AS A FUNCTION OF PRESSURE FROM THE RAMAN FREQUENCIES IN NH Br H. YURTSEVEN, Department of Physics, Middle East Technical University, 06531 Ankara, TURKEY. 47 WH. MINI-SYMPOSIUM: FIR/THz AIR/SPACE MISSIONS WEDNESDAY, JUNE 24, 2009 – 1:30 PM Room: 1000 McPHERSON LAB Chair: JOHN C. PEARSON, Jet Propulsion Laboratory, Pasadena, California WH01 INVITED TALK 30 min 1:30 ASTRONOMICAL AND ATMOSPHERIC SPECTROSCOPY IN THE SMM/THz: EXPERIMENTS, ANALYSIS, AND CATALOGS. FRANK C. DE LUCIA, Department of Physics, 191 W. Woodruff Ave., Ohio State University, Columbus, OH 43210 USA. WH02 15 min 2:05 INDIRECT TERAHERTZ SPECTROSCOPY OF MOLECULAR IONS USING HIGHLY ACCURATE AND PRECISE MID-IR SPECTROSCOPYa ANDREW A. MILLS, KYLE B. FORD, HOLGER KRECKEL, MANORI PERERA, KYLE N. CRABTREE, Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, IL 61801; BENJAMIN J. McCALL, Departments of Chemistry and Astronomy, University of Illinois at Urbana-Champaign, Urbana, IL 61801. a This work is supported by the NASA APRA Laboratory Astrophysics program. WH03 15 min 2:22 CATION FAR INFRARED VIBRATIONAL SPECTROSCOPY OF POLYCYCLIC AROMATIC HYDROCARBONS W. KONG, J. ZHANG, and F. HAN, Department of Chemistry, Oregon State University, Corvallis, OR 97331. WH04 15 min 2:39 NUMERICAL AND EXPERIMENTAL ASPECTS OF DATA ACQUISITION AND PROCESSING IN APPLICATION TO TEMPERATURE RESOLVED 3-D SUB-MILLIMETER SPECTROSCOPY FOR ASTROPHYSICS AND SPECTRAL ASSIGNMENT. IVAN R. MEDVEDEV, SARAH M. FORTMAN, CHRISTOPHER F. NEESE, and FRANK C. DE LUCIA, Department of Physics, 191 W. Woodruff Ave., Ohio State University, Columbus, OH 43210 USA. WH05 15 min 2:56 TEMPERATURE RESOLVED 3-D SUBMILLIMETER SPECTROSCOPY OF ASTRONOMICAL ‘WEEDs’. SARAH M. FORTMAN, IVAN R. MEDVEDEV, CHRISTOPHER F. NEESE, and FRANK C. DE LUCIA, Department of Physics, 191 W. Woodruff Ave., Ohio State University, Columbus, OH 43210 USA. WH06 15 min 3:13 GENERATION OF WIDELY TUNABLE FOURIER-TRANSFORM-LIMITED PULSED TERAHERTZ RADIATION USING NARROWBAND NEAR-INFRARED LASER RADIATION JINJUN LIU, CHRISTA HAASE, and FRÉDÉRIC MERKT, Laboratorium f ür Physikalische Chemie, ETHZürich, 8093 Z ürich, Switzerland. 48 Intermission WH07 INVITED TALK 30 min 3:45 THE COLOGNE DATABASE FOR MOLECULAR SPECTROSCOPY, CDMS, IN TIMES OF HERSCHEL, SOFIA, AND ALMA HOLGER S. P. MÜLLER, JÜRGEN STUTZKI, STEPHAN SCHLEMMER, I. Physikalisches Institut, Universität zu Köln, Zülpicher Str. 77, 50937 K öln, Germany. WH08 15 min 4:20 UPDATE FOR USERS OF THE METHANOL DATABASE: RECENT IMPROVEMENTS, REMAINING PROBLEMS, AND MORE COMPLICATED REGIONS LI-HONG XU, Department of Physics and Centre for Laser, Atomic, and Molecular Sciences, University of New Brunswick, Saint John, NB E2L 4L5, Canada; J.C. PEARSON, B.J. DROUIN, Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA USA 91109; J.T. HOUGEN, Optical Technology Division, National Institute of Standards and Technology, Gaitherburg, MD 20899-8441. WH09 THE JPL MILLIMETER AND SUBMILLIMETER SPECTRAL LINE CATALOG 15 min 4:37 BRIAN J. DROUIN, JOHN C. PEARSON, Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109-8099. WH10 THE ROTATIONAL SPECTRUM OF ACRYLONITRILE TO 1.67 THz 15 min 4:54 ZBIGNIEW KISIEL, LECH PSZCZÓŁKOWSKI, Institute of Physics, Polish Academy of Sciences, Al. Lotników 32/46, 02-668 Warszawa, Poland; BRIAN J. DROUIN, CAROLYN S. BRAUER, SHANSHAN YU, JOHN C. PEARSON, Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109-8099, USA. WH11 TERAHERTZ SPECTROSCOPY OF THE GROUND STATE OF METHYLAMINE (CH NH ) 15 min 5:11 SHANSHAN YU and BRIAN J. DROUIN, Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109. WH12 15 min 5:28 TERAHERTZ SPECTROSCOPY AND GLOBAL ANALYSIS OF THE BENDING VIBRATIONS OF C D C H and SHANSHAN YU, BRIAN J. DROUIN, JOHN C. PEARSON AND HERBERT M. PICKETT, Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109; VALERIO LATTANZI AND ADAM WALTERS, Centre d’Etude Spatiale des Rayonnements, Universit de Toulouse [UPS], CNRS [UMR 5187], 9 avenue du Colonel Roche, BP 44346, F-31028 Toulouse Cedex 4, France. WH13 15 min 5:45 SUBMILLIMETER SPECTROSCOPY OF THE OUT-OF-PLANE BENDING STATE OF C H CN JOHN C. PEARSON, CAROLYN S. BRAUER, SHANSHAN YU, and BRIAN J. DROUIN, JET PROPULSION LABORATORY, CALIFORNIA INSTITUTE OF TECHNOLOGY, 4800 OAK GROVE DR., PASADENA, CA 91109. 49 WI. ASTRONOMICAL SPECIES AND PROCESSES WEDNESDAY, JUNE 24, 2009 – 1:30 PM Room: 1015 MCPHERSON LAB Chair: SUSANNA WIDICUS WEAVER, Emory University, Atlanta, Georgia WI01 COSMOLOGICAL NUCLEOSYNTHESIS: THE LITHIUM PROBLEM 10 min 1:30 DOUGLAS N. FRIEDEL, ATHOL KEMBALL, and BRIAN FIELDS, Department of Astronomy, University of Illinois, 1002 W. Green St., Urbana, IL 61801. WI02 15 min 1:42 DISCOVERY OF MASSIVE YOUNG STELLAR OBJECTS IN THE GALACTIC CENTER WITH WARM CO GAS ABSORPTION DEOKKEUN AN, SOLANGE RAMIREZ, IPAC/CALTECH; KRIS SELLGREN, OHIO STATE U.; ADWIN BOOGERT, CALTECH; RICHARD ARENDT, NASA/GODDARD SPACE FLIGHT CENTER; ANGELA COTERA, SETI INSTITUTE; THOMAS ROBITAILLE, ST. ANDREWS U., UK; MATHIAS SCHULTHEIS, OBS. BESANCON, FRANCE; HOWARD A. SMITH, HARVARD-SMITHSONIAN CENTER FOR ASTROPHYSICS; SUSAN STOLOVY, SPITZER SCIENCE CENTER, CALTECH. WI03 15 min 1:59 MILLIMETER DETECTION OF AlO MAJORIS (X ): METAL OXIDE CHEMISTRY IN THE ENVELOPE OF VY CANIS E. D. TENENBAUM, L. M. ZIURYS, University of Arizona, Steward Observatory, Department of Chemistry, Arizona Radio Observatory Tucson, AZ 85721. WI04 15 min 2:16 GROUND-BASED OBSERVATIONS OF INTERSTELLAR CN AND THE C/ C RATIO AND THE EXCITATION OF CN CH IN DIFFUSE MOLECULAR CLOUDS: ADAM M. RITCHEY, STEVEN R. FEDERMAN, YARON SHEFFER, Department of Physics and Astronomy, University of Toledo, Toledo, OH 43606; and DAVID L. LAMBERT, W. J. McDonald Observatory, University of Texas, Austin, TX 78712. WI05 A SEARCH FOR INTERSTELLAR UREA WITH CARMA 15 min 2:33 H.-L. KUO, L. E. SNYDER, D. N. FRIEDEL, L. W. LOONEY, Department of Astronomy, University of Illinois at Urbana-Champaign; B. J. McCALL, Departments of Chemistry and Astronomy, University of Illinois at Urbana-Champaign, Urbana IL 61801; A. J. REMIJAN, NRAO, Charlottesville VA 22903; F.J. LOVAS, Optical Technology Division, NIST, Gaithersburg MD 20899-8441; J. M. HOLLIS, NASA/GSFC, Code 606, Greenbelt MD 20771. 50 WI06 15 min 2:50 BROADBAND AND CAVITY SPECTROSCOPY OF THIOFULMINIC ACID HCNS AND THIOISOFULMINIC ACID HSNC, AND A SYSTEMATIC ASTRONOMICAL SEARCH FOR THE FOUR [H,C,N,S] ISOMERS IN SGR B2 WITH THE GREEN BANK TELESCOPE M. C. MCCARTHY, C. A. GOTTLIEB, P. THADDEUS, Harvard-Smithsonian Center for Astrophysics, 60 Garden St., Cambridge, MA 02138, and School of Engineering & Applied Sciences, Harvard University, 29 Oxford St., Cambridge, MA 02138; M.T. MUCKLE, J.L. NEILL, B. H. PATE, Department of Chemistry, University of Virginia, McCormick Rd., Charlottesville, VA 22904-4319; SVEN THORWIRTH, MaxPlanck-Institut für Radioastronomie, Auf dem H ügel 69, 53121 Bonn, Germany; S. BR ÜNKEN, Laboratoire de Chimie Physique Moléculaire, École Polytechnique Fédérale de Lausanne, Station 6, CH-1015 Lausanne, Switzerland; ARNAUD BELLOCHE, LIES VERHEYEN, KARL M. MENTEN, Max-Planck-Institut f ür Radioastronomie, Auf dem H ügel 69, 53121 Bonn, Germany; and ANTHONY J. REMIJAN, National Radio Astronomy Observatory, 520 Edgemont Road, Charlottesville, VA 22903. WI07 GAS-GRAIN MODELING OF HNCO, HOCN, HCNO, AND HONC 15 min 3:07 DONGHUI QUAN, Chemical Physics Program, The Ohio State University, Columbus, OH 43210; ERIC HERBST, Departments of Physics, Astronomy, & Chemistry, The Ohio State University, Columbus, OH 43210. Intermission WI08 THERMALIZATION OF INTERSTELLAR CO 10 min 3:40 TAKESHI OKA, Department of Astronomy and Astrophysics and Department of Chemistry, The Enrico Fermi Institute, University of Chicago, Chicago, IL 60637; HAN XIAO, and PHILLIP LYNCH, Department of Statistics, University of Chicago, Chicago, IL 60637. WI09 15 min 3:52 VARIABILITY OF THE COSMIC-RAY IONIZATION RATE IN DIFFUSE MOLECULAR CLOUDS NICK INDRIOLO, Department of Astronomy, University of Illinois at Urbana-Champaign, Urbana, IL 61801; THOMAS R. GEBALLE, Gemini Observatory, Hilo, HI 96720; TAKESHI OKA, Department of Astronomy & Astrophysics and Department of Chemistry, University of Chicago, Chicago, IL 60637; BENJAMIN J. McCALL, Departments of Astronomy and Chemistry, University of Illinois at Urbana-Champaign, Urbana, IL 61801. WI10 CAN WE USE METASTABLE HELIUM TO TRACE THE COSMIC-RAY IONIZATION RATE? 15 min 4:09 NICK INDRIOLOa , Department of Astronomy, University of Illinois at Urbana-Champaign, Urbana, IL 61801; LEWIS M. HOBBS, University of Chicago, Yerkes Observatory, Williams Bay, WI 53191; KENNETH H. HINKLE, National Optical Astronomy Observatories, Tucson, AZ 85726; BENJAMIN J. McCALL, Departments of Astronomy and Chemistry, University of Illinois at Urbana-Champaign, Urbana, IL 61801. a nindrio2@illinois.edu 51 WI11 15 min 4:26 SPECTROSCOPIC STUDIES OF THE TURES H + H REACTION AT ASTROPHYSICALLY RELEVANT TEMPERA- BRIAN A. TOM, BRETT A. McGUIRE, LAUREN E. MOORE, THOMAS J. WOOD, Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, IL 61801; BENJAMIN J. McCALL, Departments of Chemistry and Astronomy, University of Illinois at Urbana-Champaign, Urbana, IL 61801. WI12 15 min 4:43 PRODUCT BRANCHING RATIOS OF THE REACTION OF CO WITH H AND ITS ISOTOPOMERS HUA-GEN YU, Department of Chemistry, Brookhaven National Laboratory, Upton, NY 11973. WI13 A NEW INTERSTELLAR MODEL FOR HIGH-TEMPERATURE TIME-DEPENDENT KINETICS 15 min 5:00 NANASE HARADA, Department of Physics, The Ohio State University, Columbus OH 43210; ERIC HERBST, Departments of Physics, Astronomy, and Chemistry, The Ohio State University, Columbus, OH 43210. WI14 THE OPTICAL SPECTRUM OF THIOZONE S AND OTHER SULFUR RICH SYSTEMS 15 min 5:17 DAMIAN L. KOKKIN, MICHAEL C. McCARTHY, and PATRICK THADDEUS, Harvard-Smithsonian Center for Astrophysics, 60 Garden St., Cambridge, MA 02138, and School of Engineering & Applied Sciences, Harvard University, 29 Oxford St., Cambridge, MA 02138. WI15 10 min 5:34 LABORATORY MEASUREMENT OF THE CO CAMERON BANDS AND VISIBLE EMISSIONS FOLLOWING VUV PHOTODISSOCIATION OF CO K. S. KALOGERAKIS, C. ROMANESCU, T. G. SLANGER, SRI International, Mol. Phys. Lab., Menlo Park, CA 94025; L. C. LEE, San Diego State Univ., Dept. Elect. & Comp. Eng., San Diego, CA 92182; M. AHMED and K. R. WILSON , Univ. Calif. Berkeley, Lawrence Berkeley Lab., Div. Chem. Sci., Berkeley, CA 94720. WI16 Post-deadline Abstract – Original Abstract Withdrawn 15 min 5:46 AN EXHAUSTIVE ISOTOPIC STUDY OF THE ABUNDANT ASTRONOMICAL MOLECULE CYCLOPROPENYLIDENE, c-C H SILVIA SPEZZANO, C. A. GOTTLIEB, M. C. McCARTHY AND P. THADDEUS, Harvard-Smithsonian Center for Astrophysics, 60 Garden St., Cambridge, MA 02138, and School of Engineering & Applied Sciences, Harvard University, 29 Oxford St., Cambridge, MA 02138. 52 WJ. MINI-SYMPOSIUM: CONICAL INTERSECTIONS WEDNESDAY, JUNE 24, 2009 – 1:30 PM Room: 2015 McPHERSON LAB Chair: SPIRIDOULA MATSIKA, Temple University, Philadelphia, Pennsylvania WJ01 INVITED TALK WATCHING ELECTRONS AT CONICAL INTERSECTIONS AND FUNNELS 30 min 1:30 DAVID M. JONAS, ERIC R. SMITH, WILLIAM K. PETERS, KATHERINE A. KITNEY, Department of Chemistry and Biochemistry, University of Colorado, Boulder, CO 80309-0215. WJ02 15 min 2:05 THE CONICAL INTERSECTIONS BETWEEN L and L STATES IN TRYPTAMINE AND INDOLE Ch. BRAND, Institut für Physikalische Chemie I, Heinrich-Heine-Universit ät, Universitätsstraße 26.43.02.43 D-40225 D üsseldorf, Germany; J. KÜPPER, Fritz-Haber-Institut der Max-Planck-Gesellschaft, 14195 Berlin, Germany; W. LEO MEERTS, Molecular and Biophysics Group, Institute for Molecules and Materials,Radboud University, 6500 GL Nijmegen, The Netherlands; D. W. PRATT, University of Pittsburgh, Department of Chemistry, Pittsburgh, PA 15260, USA; J ÖRG TATCHEN, Chemical Physics Department, Weizmann Institute of Science, 76100 Rehovot, Israel; and M. SCHMITT, Institut f ür Physikalische Chemie I, HeinrichHeine-Universität, Universitätsstraße 26.43.02.43 D-40225 D üsseldorf, Germany. WJ03 15 min 2:22 HIGH RESOLUTION SPECTROSCOPY OF INDOLE DERIVATIVES NEAR CONICAL INTERSECTIONS: TRYPTAMINE AND INDOLE Ch. BRAND, Institut für Physikalische Chemie I, Heinrich-Heine-Universit ät, Universitätsstraße 26.43.02.43 D-40225 D üsseldorf, Germany; J. KÜPPER, Fritz-Haber-Institut der Max-Planck-Gesellschaft, 14195 Berlin, Germany; I. KALKMAN, W. LEO MEERTS, Molecular and Biophysics Group, Institute for Molecules and Materials,Radboud University, 6500 GL Nijmegen, The Netherlands; D. W. PRATT, University of Pittsburgh, Department of Chemistry, Pittsburgh, PA 15260, USA; and M. SCHMITT, Institut f ür Physikalische Chemie I, Heinrich-Heine-Universit ät, Universitätsstraße 26.43.02.43 D-40225 D üsseldorf, Germany. WJ04 15 min 2:39 MULTI-STATE VIBRONIC INTERACTIONS IN FLUORINATED BENZENE RADICAL CATIONS. S. FARAJI, H. KÖPPEL, Theoretische Chemie, Physikalisch-Chemisches Institut, Universit ät Heidelberg, Im Neuenheimer Feld 229, D-69120 Heidelberg, Germany. WJ05 MULTIPHOTON IONIZATION AND DISSOCIATION OF DIAZIRINE 15 min 2:56 ANDREW K. MOLLNER, I. FEDOROV, L. KOZIOL, A. I. KRYLOV, H. REISLER, Department of Chemistry, University of Southern California, Los Angeles, CA 90089. 53 WJ06 15 min 3:13 STRUCTURE OF THE PHOTOCHEMICAL REACTION PATHWAYS POPULATED VIA THE PROMOTION of CF I and CH I INTO THEIR FIRST ELECTRONICALLY EXCITED STATES P. Z. EL-KHOURY, A. N TARNOVSKY, and M. OLIVUCCI, Department of Chemistry and Center for Photochemical Sciences, Bowling Green State University, Bowling Green, OH 43403. Intermission WJ07 10 min 3:45 THE FLUORESCENCE OF THE WURSTER’S BLUE RADICAL CATION IS CONTROLLED BY A CONICAL INTERSECTION ELENA N. LARICHEVA and MASSIMO OLIVUCCI, Department of Chemistry and Center for Photochemical Sciences, Bowling Green State University, Bowling Green, OH 43403, USA; JAKOB GRILJ and ERIC VAUTHEY, Physical Chemistry Department, University of Geneva, 1211 Geneva, Switzerland. WJ08 15 min 3:57 RELATIVISTIC JAHN-TELLER EFFECTS IN THE QUARTET STATES OF K AND RB : A VIBRATIONAL ANALYSIS OF THE 2 E 1 A ELECTRONIC TRANSITIONS BASED ON AB INITIO CALCULATIONS A. W. HAUSER, G. AUBÖCK, C. CALLEGARI and W. E. ERNST, Institute of Experimental Physics, Graz University of Technology, Petersgasse 16, A-8010 Graz, Austria. WJ09 15 min 4:14 COLLISIONAL QUENCHING OF OH A BY H AND N : DYNAMICAL OUTCOMES LOGAN P. DEMPSEY, TIMOTHY D. SECHLER, CRAIG MURRAY, MARSHA I. LESTER, Department of Chemistry, University of Pennsylvania, Philadelphia, PA 19104-6323; SPIRIDOULA MATSIKA, Department of Chemistry, Temple University, Philadelphia, Pennsylvania 19122-6014. WJ10 15 min 4:31 EFFECTS OF ASYMMETRIC DEUTERATION ON THE ROTATIONAL LEVEL STRUCTURE OF JAHN-TELLER ACTIVE METHOXY RADICALS DMITRY G. MELNIK, MING-WEI CHEN, JINJUN LIU, a and TERRY A. MILLER, Laser Spectroscopy Facility, Department of Chemistry, The Ohio State University, 120 W. 18th Avenue, Columbus, Ohio 43210; ROBERT F. CURL, Department of Chemistry and Rice Quantum Institute, Rice University, Houston TX, 77005; C. BRADLEY MOORE, Department of Chemistry, University of California, Berkeley CA, 94720. a present address: Laboratory of Physical Chemistry, ETH Zurich, Wolfgang-Pauli-Str. 10, 8093 Zurich, Switzerland WJ11 15 min 4:48 STATE OF THE NITRATE RADICAL NO THE JAHN-TELLER (JT) EFFECT IN THE KANA TAKEMATSU, NATHAN EDDINGSAAS, and MITCHIO OKUMURA, Arthur Amos Noyes Laboratory of Chemical Physics, California Institute of Technology, Pasadena, California 91125; JOHN STANTON, Department of Chemistry, University of Texas at Austin, Austin, TX 78712. 54 RA. INFRARED/RAMAN THURSDAY, JUNE 25, 2009 – 8:30 AM Room: 160 MATH ANNEX Chair: NATHALIE PICQUE, CNRS Université de Paris-Sud, Orsay, France RA01 INFRARED SPECTRA OF TWO ISOMERS OF THE OCS-C H AND OCS-C D 15 min 8:30 MAHIN AFSHARI, M. DEHGHANY, J. N. OLIAEE, N. MOAZZEN-AHMADI, Department of Physics and Astronomy, University of Calgary, Calgary, AB T2N 1N4, Canada; A.R.W. MCKELLAR, Steacie Institute for Molecular Sciences, National Research Council of Canada, Ottawa, ON K1A 0R6, Canada. RA02 15 min 8:47 INFRARED SPECTRA OF CARBONYL SULFIDE-ACETYLENE TRIMERS: OCS-(C H ) AND TWO ISOMERS OF (OCS) -C H MAHIN AFSHARI, M. DEHGHANY, J. N. OLIAEE, N. MOAZZEN-AHMADI, Department of Physics and Astronomy, University of Calgary, Calgary, AB T2N 1N4, Canada; A.R.W. MCKELLAR, Steacie Institute for Molecular Sciences, National Research Council of Canada, Ottawa, ON K1A 0R6, Canada. RA03 15 min 9:04 FUNDAMENTAL AND TORSIONAL COMBINATION BANDS OF N O-C H AND N O-C D IN THE N O REGION M. DEHGHANY, MAHIN AFSHARI, J. N. OLIAEE, N. MOAZZEN-AHMADI, Department of Physics and Astronomy, University of Calgary, Calgary, AB T2N 1N4, CANADA; A.R.W. MCKELLAR, Steacie Institute for Molecular Sciences, National Research Council of Canada, Ottawa, ON K1A 0R6, CANADA. RA04 INFRARED SPECTROSCOPY OF TWO ISOMERS OF THE OCS-CS COMPLEX 15 min 9:21 J. N. OLIAEE, M. DEHGHANY, MAHIN AFSHARI, N. MOAZZEN-AHMADI, Department of Physics and Astronomy, University of Calgary, 2500 University Dr., N.W., Calgary, Alberta T2N 1N4, Canada; A.R.W. McKELLAR, Steacie Institute for Molecular Sciences, National Research Council of Canada, Ottawa, Ontario, K1A 0R6, Canada. RA05 NEW INFRARED SPECTRA OF THE NITROUS OXIDE TRIMER 15 min 9:38 M. DEHGHANY, MAHIN AFSHARI, J. N. OLIAEE, N. MOAZZEN-AHMADI, Department of Physics and Astronomy, University of Calgary, Calgary, AB T2N 1N4, CANADA; A.R.W. MCKELLAR, Steacie Institute for Molecular Sciences, National Research Council of Canada, Ottawa, ON K1A 0R6, CANADA. Intermission 55 RA06 15 min INFRARED SPECTROSCOPY OF 7-AZAINDOLE TAUTOMERIC DIMER AND ITS ISOTOPOMERS 10:20 HARUKI ISHIKAWA, HIROKI YABUGUCHI, YUJI YAMADA, AKIMASA FUJIHARA, KIYOKAZU FUKE, Department of Chemistry, Graduate School of Science, Kobe University, Nada-ku, Kobe 657-8501, Japan. RA07 15 min INFRARED SPECTRA OF M (2-AMINO-1-PHENYL ETHANOL)(H O) Ar 10:37 (M=Na, K) AMY L. NICELY and JAMES M. LISY, Department of Chemistry, University of Illinois at UrbanaChampaign, Urbana, IL 61801. RA08 15 min 10:54 SPECTROCSOPY AND STRUCTURE OF CATIONIC METAL CARBONYL SYSTEMS M(CO) M=V, CO N=1-10 ALLEN M. RICKS, and MICHAEL A. DUNCAN, University of Georgia, Athens Ga.. RA09 POLAR (ACYCLIC) ISOMER OF FORMIC ACID DIMER: RAMAN SPECTROSCOPY STUDY 10 min 11:11 ROMAN M. BALABIN, Department of Chemistry and Applied Biosciences, ETH Zurich, 8093 Zurich, Switzerland. RA10 AR-PREDISSOCIATION SPECTROSCOPY OF PROTONATED IMIDAZOLE CLUSTERS 15 min 11:23 GEORGE H. GARDENIER, MARK A. JOHNSON, Sterling Chemistry Laboratory, Yale University, P.O Box 208107, New Haven, CT, 06520. RA11 15 min 11:40 INFRARED SPECTROSCOPY OF HYDRATED DOUBLY-CHARGED METAL IONS PRODUCED BY ELECTROSPRAY IONIZATION HARUKI ISHIKAWA, TORU EGUCHI, AKIMASA FUJIHARA, YUJI YAMADA, KIYOKAZU FUKE, Department of Chemistry, Graduate School of Science, Kobe University, Nada-ku, Kobe 657-8501, Japan. 56 RB. RADICALS AND IONS THURSDAY, JUNE 25, 2009 – 8:30 AM Room: 170 MATH ANNEX Chair: JINJUN LIU, ETH Zurich, Zurich, Switzerland RB01 15 min 8:30 STUDY OF TWO-PHOTON RESEONANT FOUR WAVE SUM MIXING IN XEON AND ITS COMPETITION WITH THE FOUR WAVE DIFFERENCE MIXING W. AL-BASHEER, Y. J. SHI, Department of Chemistry, University of Calgary, Calgary, Alberta, T2N 1N4. RB02 15 min 8:47 INFRARED SPECTROSCOPY OF H O N ) (n=1,2,3) COMPLEXES T. CHENG, B. BANDYOPADHYAY, M. A. DUNCAN, Department of Chemistry, University of Georgia, Athens, GA 30602-2556. RB03 INFRARED SPECTROSCOPY OF PROTONATED WATER-BENZENE CLUSTERS 15 min 9:04 T. CHENG, B. BANDYOPADHYAY, M.A. DUNCAN, Department of Chemistry, University of Georgia Athens, GA 30602. RB04 15 min 9:21 HALF-SANDWICH COMPLEXES OF GROUP III (Sc, Y, and La) METALS WITH CYCLOOCTATERAENE SUDESH KUMARI, JUNG SUP LEE, and DONG-SHENG YANG, Department of Chemistry, University of Kentucky, Lexington, KY 40506-0055. RB05 ROTATIONAL CONFORMERS OF GROUP VI (Cr, Mo, and W) METAL BIS(TOLUENE) PLEXES 15 min 9:38 COM- JUNG SUP LEE, SUDESH KUMARI, and DONG-SHENG YANG, Department of Chemistry, University of Kentucky, Lexington, KY 40506-0055. Intermission RB06 15 min 10:10 KINETIC AND THERMODYNAMIC STUDIES OF GASEOUS METALLO-ORGANIC CATIONIC COMPLEXES S. JASON DEE, VANESSA A. CASTLEBERRY, OTSMAR J. VILLARROEL, IVANNA E. LABOREN, SARAH E. FREY and DARRIN J. BELLERT, Department of Chemistry and Biochemistry, Baylor University, Waco, Texas, 76798. 57 RB07 15 min 10:27 A STUDY OF THE HYDROXYCYCLOHEXADIENYL RADICAL ABSORPTION USING TIME-RESOLVED RESONANCE RAMAN SPECTROSCOPY DEANNA M. O’DONNELL, G.N.R. TRIPATHI, NICOLE R. BRINKMANN, Department of Chemistry and Radiation Laboratory, University of Notre Dame, Notre Dame, IN 46545. RB08 PHOTOELECTRON SPECTROSCOPY OF SUBSTITUTED PHENYLNITRENES 15 min 10:44 NELONI R. WIJERATNE, MARIA DA FONTE and PAUL G. WENTHOLD, Department of Chemistry, Purdue University, West Lafayette, IN 47907-2084. RB09 Post-deadline Abstract – Original Abstract Withdrawn 15 min 11:01 ON THE MAGNITUDE OF THE NONADIABATIC ERROR FOR HIGHLY COUPLED RADICALS JF STANTON, Department of Chemistry and Biochemistry, University of Texas at Austin, Austin, TX 78712. RB10 15 min 11:18 CONFORMATIONS OF CATIONIZED PEPTIDES. DETERMINATION OF LIGAND BINDING GEOMETRIES BY IRMPD SPECTROSCOPY ROBERT C. DUNBAR, Chemistry Department, Case Western Reserve Univ., Cleveland, OH 44106; JEFFREY STEILL, JOS OOMENS, FOM Institute for Plasma Physics, Nieuwegein, Netherlands; NICK C. POLFER, Chemistry Department, University of Florida, Gainesville, FL 32611. RB11 15 min 11:35 PHOTODAMAGE TO ISOLATED MONONUCLEOTIDES: PHOTODISSOCIATION SPECTRA AND FRAGMENT CHANNELS JESSE C. MARCUM, AMIT HALEVI, J. MATHIAS WEBER, JILA, NIST, and Department of Chemistry and Biochemistry, University of Colorado, Boulder, Co 80309. 58 RC. MICROWAVE THURSDAY, JUNE 25, 2009 – 8:30 AM Room: 1000 McPHERSON Lab Chair: LUCY ZIURYS, University of Arizona, Tucson, Arizona RC01 THE DISCOVERY OF BRIDGED HPSI BY ROTATIONAL SPECTROSCOPY 15 min 8:30 M. C. MCCARTHY, V. LATTANZI, P. THADDEUS, Harvard-Smithsonian Center for Astrophysics, 60 Garden St., Cambridge, MA 02138, and School of Engineering & Applied Sciences, Harvard University, 29 Oxford St., Cambridge, MA 02138; D. T. HALFEN, L. M. ZIURYS, Department of Chemistry, Department of Astronomy, and Steward Observatory, University of Arizona, Tucson, AZ, 85721; SVEN THORWIRTH, MaxPlanck-Institut für Radioastronomie, Auf dem H ügel 69, 53121 Bonn, Germany; AND J. GAUSS, Institut für Physikalische Chemie, Johannes Gutenberg-Universit ät Mainz, Jakob-Welder-Weg 11, 55128 Mainz, Germany. RC02 15 min 8:47 FOURIER TRANSFORM MICROWAVE SPECTROSCOPY AND MOLECULAR STRUCTURE OF THE 1,1DIFLUOROETHYLENE–HF COMPLEX MARK D. MARSHALL, HELEN O. LEUNG, TASHA L. DRAKE, TADEUSZ PUDLIK, NAZIR SAVJI, and DANIEL W. McCUNE, Department of Chemistry, Amherst College, P.O. Box 5000, Amherst, MA 010025000. RC03 THE STRUCTURE OF THE TRANS-1,2-DIFLUOROETHYLENE–HF COMPLEX 15 min 9:04 HELEN O. LEUNG, MARK D. MARSHALL, and BRENT K. AMBERGER, Department of Chemistry, Amherst College, P.O. Box 5000, Amherst, MA 01002-5000. RC04 15 min 9:21 THE IMPACT OF LONG RANGE INTERACTIONS ON LOW TEMPERATURE PRESSURE BROADENING: THE CASE OF HE–OCS K. N. SALB, D. R. WILLEY, Department of Physics, Allegheny College, Meadville, PA 16335. RC05 A MICROWAVE INVESTIGATION OF THE CO -PYRIDINE VAN DER WAALS COMPLEX 15 min 9:38 J. L. DORAN, B. J. HON, and K. R. LEOPOLD, Department of Chemistry, University of Minnesota, Minneapolis, MN 55455.. RC06 ROTATIONAL SPECTRA AND STRUCTURE OF PHENYLACETYLENE- COMPLEX 15 min 9:55 MAUSUMI GOSWAMI and E. ARUNAN, Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore 560012, India. 59 RC07 10 min 10:12 ROTATIONAL SPECTROSCOPIC AND THEORETICAL INVESTIGATIONS ON BENZENE-ETHYLENE COMPLEX AISWARYA LAKSHMI P. and E. ARUNAN, Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore 560012, India. Intermission RC08 MICROSOLVATION OF BUILDING BLOCKS 15 min 10:40 V. VAQUERO, I. PENA, S. MATA, J. C. L ÓPEZ, and J. L. ALONSO, Grupo de Espectroscopı́a Molecular (GEM), Departamento de Quı́mica Fı́sica y Quı́mica Inorgánica, Facultad de Ciencias, Universidad de Valladolid, E-47005 Valladolid, Spain. RC09 10 min 10:57 SIZING THE UBBELHODE EFFECT: THE ROTATIONAL SPECTRUM OF TERT-BUTYLALCOHOL DIMER SHOUYUAN TANG, College of Bioengineering, ChongQing University, ChongQing, 400044, P. R. China; IRENA MAJERZ, Faculty of Chemistry, University of Wroclaw, Joliot-Curie 14, 50-383 Wroclaw, Poland; WALTHER CAMINATI, Dipartimento di Chimica ”G. Ciamician” dell’Universit à, Via Selmi 2, I40126 Bologna, Italy. RC10 15 min 11:09 CALCULATIONS AND GAS PHASE MEASUREMENTS OF THE COMPLEX FORMED WITH FERROCENE AND HCL ADAM M. DALY, STEPHEN G. KUKOLICH, DEPARTMENT OF CHEMISTRY, UNIVERISTY OF ARIZONA, TUCSON, AZ. RC11 15 min 11:26 PURE ROTATIONAL AND ULTRAVIOLET-MICROWAVE DOUBLE RESONANCE SPECTROSCOPY OF TWO WATER COMPLEXES OF PARA-METHOXYPHENYLETHYLAMINE JUSTIN L. NEILL, MATT T. MUCKLE, and BROOKS H. PATE, Department of Chemistry, University of Virginia, Charlottesville, VA 22904; RYAN G. BIRD and DAVID W. PRATT, Department of Chemistry, University of Pittsburgh, Pittsburgh, PA 15260. RC12 15 min A MICROWAVE AND AB INITIO STUDY OF THE NITRIC ACID - TRIMETHYLAMINE COMPLEX 11:43 GALEN SEDO, Department of Chemistry, The University of Manitoba, Winnipeg, MB Canada R3T 2N2; KENNETH R. LEOPOLD, Department of Chemistry, The University of Minnesota, Minneapolis, MN 55455. RC13 THE FREE JET MICROWAVE SPECTRUM OF 2-PHENYLETHYLAMINE-WATER 10 min 12:00 SONIA MELANDRI, B. MICHELA GIULIANO, ASSIMO MARIS and WALTHER CAMINATI, Dipartimento di Chimica Ciamician, Universit à di Bologna, via Selmi 2,40126 Bologna, Italy. 60 RD. MINI-SYMPOSIUM: CAVITY ENHANCED SPECTROSCOPY THURSDAY, JUNE 25, 2009 – 8:30 AM Room: 1015 McPHERSON LAB Chair: YUNJIE XU, University of Alberta, Edmonton, AB, Canada RD01 INVITED TALK 30 min 8:30 NITROGEN OXIDES, AEROSOLS AND OXYGENATED VOC: APPLICATIONS OF VISIBLE CAVITY ENHANCED OPTICAL EXTINCTION SPECTROSCOPY TO ATMOSPHERIC MEASUREMENTS STEVEN S. BROWN, NOAA Earth System Research Laboratory, Boulder, CO 80305. RD02 15 min 9:05 TRANSITION OF THE DETECTION OF THE MAGNETIC DIPOLE-ALLOWED ORIGIN BAND OF THE NITRATE RADICAL NO KANA TAKEMATSU, NATHAN EDDINGSAAS, and MITCHIO OKUMURA, Arthur Amos Noyes Laboratory of Chemical Physics, California Institute of Technology, Pasadena, California 91125; JOHN STANTON, Department of Chemistry, University of Texas at Austin, Austin, TX 78712. RD03 15 min 9:22 NO TRACE MEASUREMENTS BY OPTICAL-FEEDBACK CAVITY-ENHANCED ABSORPTION SPECTROSCOPY I. VENTRILLARD-COURTILLOT, Th. DESBOIS, T. FOLDES and D. ROMANINI, Laboratoire de Spectrométrie Physique, CNRS UMR5588, Univ. J. Fourier de Grenoble, St Martin d’H ères, France. RD04 15 min 9:39 MEASUREMENTS OF PEROXY RADICALS USING CHEMICAL AMPLIFICATION/CAVITY RING-DOWN SPECTROSCOPY YINGDI LIU, Department of Chemistry, University of California, Riverside, CA 92521; RODRIGO MORALES-CUETO, Instituto de Quimica, Universidad Nacional Autonoma de Mexico, Ciudad Universitaria, 04510, Mexico, D.F., Mexico; JAMES HARGROVE, DAVID MEDINA, Department of Chemistry, University of California, Riverside, CA 92521; and JINGSONG ZHANG, Department of Chemistry and Air Pollution Research Center, University of California, Riverside, CA 92521. RD05 15 min 9:56 QUANTITATIVE MEASUREMENTS OF ABSORPTION CROSS-SECTIONS BY DUAL WAVELENGTH CAVITY RING-DOWN SPECTROSCOPY RABI CHHANTYAL PUN, PHILLIP THOMAS, DMITRY G. MELNIK, and TERRY A. MILLER, Laser Spectroscopy Facility, Department of Chemistry, The Ohio State University, 120 W. 18th Avenue, Columbus, Ohio 43210. Intermission 61 RD06 CAVITY ATTENUATED PHASE SHIFT-BASED MONITORING OF ATMOSPHERIC SPECIES 10 min 10:30 P. L. KEBABIAN, T. B. ONASCH, S. C. HERNDON, E. C. WOOD, J. WORMHOUDT, and A. FREEDMAN, Aerodyne Research, Inc., Billerica, MA 01821. RD07 15 min 10:42 DETECTION OF IODINE MONOXIDE RADICALS IN THE MARINE BOUNDARY LAYER USING AN OPEN-PATH CAVITY RING-DOWN SPECTROMETER RYUICHI WADA, Solar-Terrestrial Environment Laboratory, Nagoya University, Nagoya, 464-8601, Japan; JOSEPH M. BEAMES, School of Chemistry, University of Bristol, Bristol, BS8 1TS, United Kingdom; and ANDREW J. ORR-EWING, School of Chemistry, University of Bristol, Bristol, BS8 1TS, United Kingdom. RD08 ROTATIONALLY RESOLVED ABSORPTION OF IN THE VISIBLE AT 90K 15 min 10:59 YASNAHIR PEREZ-DELGADO and CARLOS E. MANZANARES, Department of Chemistry and Biochemistry, Baylor University, Waco, Texas, 76798. RD09 CALCULATIONS AND FIRST QUANTITATIVE LABORATORY MEASUREMENTS OF O QUADRUPOLE LINE INTENSITIES AND POSITIONS 15 min 11:16 -BAND ELECTRIC DAVID A. LONG, MITCHIO OKUMURA, Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125, USA; CHARLES E. MILLER, HERBERT M. PICKETT, Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109, USA; DANIEL K. HAVEY, JOSEPH T. HODGES, Process Measurements Division, National Institute of Standards and Technology, 100 Bureau Drive, Gaithersburg, MD 20899, USA. RD10 15 min 11:33 EXPERIMENTAL LINE PARAMETERS OF HIGH-J TRANSITIONS IN THE O A-BAND USING FREQUENCYSTABILIZED CAVITY RING-DOWN SPECTROSCOPY DANIEL K. HAVEY, JOSEPH T. HODGES, Process Measurements Division, National Institute of Standards and Technology, 100 Bureau Drive, Gaithersburg, MD 20899, USA; DAVID A. LONG, MITCHIO OKUMURA, Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125, USA; CHARLES E. MILLER, Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109, USA. 62 RE. MINI-SYMPOSIUM: CONICAL INTERSECTIONS THURSDAY, JUNE 25, 2009 – 8:30 AM Room: 2015 McPHERSON LAB Chair: SCOTT REID, Marquette University, Milwaukee, Wisconsin RE01 INVITED TALK 30 min 8:30 FIRST PRINCIPLES DYNAMICS AROUND CONICAL INTERSECTIONS: THE ROLE OF THE ENVIRONMENT AND INTERSECTION TOPOGRAPHY TODD J. MARTINEZ, Department of Chemistry, Stanford University, Stanford, CA. RE02 THREE-STATE CONICAL INTERSECTIONS IN BIOLOGICALLY RELEVANT MOLECULES 15 min 9:05 S. MATSIKA and K. A. KISTLER , Department of Chemistry, Temple University, Philadelphia, PA 19122. RE03 15 min 9:22 PHOTO-REACTIVITY OF A PUSH-PULL MEROCYANINE IN A STATIC ELECTRIC FIELDS: A THREE STATE MODEL OF ISOMERIZATION REACTIONS INVOLVING CONICAL INTERSECTIONS S. ZILBERG, X. F. XU, A. KAHAN and Y. HAAS, Institute of Chemistry and the Farkas Center for Light Induced Processes The Hebrew University of Jerusalem, Jerusalem, Israel; ,. RE04 15 min 9:39 SUBPICOSECOND EXCITED STATE LIFETIMES IN DNA POLYMERS REQUIRE UNSTACKED BASES KIMBERLY DE LA HARPE, CHARLENE SU, and BERN KOHLER, Department of Chemistry, The Ohio State University, Columbus, OH 43210. RE05 DARK STATES IN SINGLE DNA BASES AND DNA BASE POLYMERS 15 min 9:56 BERN KOHLER, PATRICK M. HAREa , and CHRIS T. MIDDLETON b, Department of Chemistry, The Ohio State University, Columbus, OH 43210. a Current b Current address: Department of Chemistry, Northern Kentucky University, Highland Heights, KY 41099 address: Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706 Intermission RE06 15 min 10:30 NON-RADIATIVE RELAXATION OF ELECTRONICALLY EXCITED DNA OLIGOMERS: PROTON COUPLED CHARGE TRANSFER ADRIAN W. LANGE and JOHN M. HERBERT, Ohio State University Department of Chemistry, Columbus, OH. 63 RE07 EXCITED STATES OF NON-ISOLATED CHROMOPHORES 15 min 10:47 S. MATSIKA and C. KOZAK and K. KISTLER, Department of Chemistry, Temple University, Philadelphia, PA 19122. RE08 HOONO ISOMERIZATION TO HONO INVOLVING CONICAL INTERSECTIONS 10 min 11:04 T. J. DHILIP KUMAR, Department of Atmospheric, Oceanic and Space Sciences, University of Michigan, Ann Arbor, MI 48105; JOHN F. STANTON, Institute for Theoretical Chemistry, Department of Chemistry and Biochemistry, University of Texas at Austin, Austin, TX 78712; and JOHN R. BARKER, Department of Atmospheric, Oceanic and Space Sciences, University of Michigan, Ann Arbor, MI 48105. RE09 15 min 11:16 H-ATOM ELIMINATION CHANNEL IN UV PHOTODISSOCIATION OF N-PROPYL AND ISO-PROPYL RADICALS: THE ROLE OF CONICAL INTERSECTIONS XIANFENG ZHENG, WEIDONG ZHOU, YU SONG, Department of Chemistry, University of California, Riverside, CA 92521; and JINGSONG ZHANG, Department of Chemistry and Air Pollution Research Center, University of California, Riverside, CA 92521. RE10 10 min 11:33 CONFORMER SELECTIVE AND VIBRATIONALLY MEDIATED PHOTODISSOCIATION STUDY OF PROPANAL CATION LEI SHEN, MYUNG HWA KIM, BAILIN ZHANG, ARTHUR G. SUITS, Department of Chemistry, Wayne State University, Detroit, MI, 48202. 64 RF. ELECTRONIC THURSDAY, JUNE 25, 2009 – 1:30 PM Room: 160 MATH ANNEX Chair: ANTHONY MERER, Academia Sinica, Taipei, Taiwan RF01 10 min 1:30 INTRACAVITY LASER ABSORPTION SPECTROSCOPY OF PLATINUM FLUORIDE IN THE NEAR INFRARED LEAH C. O’BRIEN, RACHEL A. HARRIS, Department of Chemistry, Southern Illinois University, Edwardsville, IL 62026-1652; JAMES J. O’BRIEN, Department of Chemistry, University of Missouri, St Louis, MO 63121-4499. RF02 10 min 1:42 INTRACAVITY LASER ABSORPTION SPECTROSCOPY OF NICKEL FLUORIDE IN THE NEAR INFRARED JAMES J. O’BRIEN, Department of Chemistry, University of Missouri, St Louis, MO 63121-4499; LEAH C. O’BRIEN, RACHEL A. HARRIS, Department of Chemistry, Southern Illinois University, Edwardsville, IL 62026-1652. RF03 15 min 1:54 HIGH RESOLUTION LASER SPECTROSCOPY OF IRIDIUM MONOFLUORIDE AND IRIDIUM MONOCHLORIDE A. G. ADAM, L. E. DOWNIE, S. J. FORAN, and A. D. GRANGER, Chemistry Department, and Centre for Lasers, and Atomic, and Molecular Sciences, University of New Brunswick, Fredericton, NB, E3B 5A3; and D. FORTHOMME, C. LINTON, and D. W. TOKARYK, Physics Department, and Centre for Lasers, and Atomic, and Molecular Sciences, University of New Brunswick, Fredericton, NB, E3B 5A3. RF04 15 min 2:11 ANALYSIS OF THE MAGNETIC HYPERFINE STRUCTURE IN THE MONOFLUORIDE, IrF BAND SYSTEM OF IRIDIUM HAILING WANG, XIUJUAN ZHUANG AND TIMOTHY C. STEIMLE , Department of Chemistry and Biochemistry, Arizona State University, Tempe,AZ 85287; COLAN LINTON, Center for Lasers, Atomic and Molecular Sciences and Physics Department, University of New Brunswick, Fredericton, NB Canada E3B 5A3. RF05 LASER INDUCED FLUORESCENCE SPECTRUM OF IRIDIUM MONOPHOSPHIDE 10 min 2:28 H.F. PANG, ANWEN LIU AND A. S-C. CHEUNG, Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong.. RF06 15 min 2:40 LASER SPECTROSCOPY OF NiI: NEW ELECTRONIC STATES AND HYPERFINE STRUCTURE A. S-C. CHEUNG, H.F. PANG, W.S. TAM, J. YE, AND J. W-H. LEUNG, Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong.. 65 Intermission RF07 X-RAY SPECTROSCOPY OF GOLD NANOPARTICLES 15 min 3:15 SULTANA N. NAHAR, M. MONTENEGRO, A.K. PRADHAN, Department of Astronomy, The Ohio State University, Columbus, OH 43210; R. PITZER, Department of Chemistry, The Ohio State University, Columbus, OH 43210. RF08 10 min 3:32 INTRACAVITY LASER ABSORPTION SPECTROSCOPY OF PLATINUM NITRIDE IN THE NEAR INFRARED LEAH C. O’BRIEN, RACHEL A. HARRIS, Department of Chemistry, Southern Illinois University, Edwardsville, IL 62026-1652; SEAN WHITTEMORE, JAMES J. O’BRIEN, Department of Chemistry, University of Missouri, St Louis, MO 63121-4499. RF09 15 min 3:44 MAGNETIC g -FACTORS AND ELECTRIC DIPOLE MOMENTS OF LANTHANIDE MONOXIDES: PrO HAILING WANG,TIMOTHY C. STEIMLE, Department of Chemistry and Biochemistry, Arizona State University, Tempe,AZ 85287; COLAN LINTON, Physics Department, University of New Brunswick, Fredericton, NB Canada E3B 5A3. RF10 THE 10 min 4:01 - BAND SYSTEM OF SrF REVISITED TIMOTHY C. STEIMLE , ANH LE, Department of Chemistry and Biochemistry, Arizona State University, Tempe,AZ 85287. RF11 POPULATION DEPLETION SPECTROSCOPY OF STRONTIUM MONOMETHOXIDE 15 min 4:13 D. FORTHOMME , L. E. DOWNIE, A. D. GRANGER, A. G. ADAM, C. LINTON, D. TOKARYK, Centre for Laser, Atomic and Molecular Sciences, Physics and Chemistry Departments, University of New Brunswick, Fredericton, NB, Canada, E3B 5A3; W. S. HOPKINS , Physical and Theoretical Chemistry Laboratory, Department of Chemistry, University of Oxford, Oxford, U.K. OX1 3QZ. RF12 15 min 4:30 LASER SPECTROSCOPY OF BaOH AND BaOD: ANOMALOUS SPIN-ORBIT COUPLING IN THE STATE J. D. TANDY, J.-G. WANG, and P. F. BERNATH, Department of Chemistry, University of York, Heslington, York, YO10 5DD, UK. RF13 THE OPTICAL STARK SPECTRA OF CoF AND CoH 15 min 4:47 HAILING WANG, XIUJUAN ZHUANG, AND TIMOTHY C. STEIMLE , Department of Chemistry and Biochemistry, Arizona State University, Tempe,AZ 85287. 66 RF14 15 min 5:04 A NEGATIVE ION PHOTOELECTRON SPECTROSCOPIC AND COMPUTATIONAL STUDY OF Mo AND Mo BEAU J. BARKER, SUNIL BAIDAR, SEAN M. CASEY and DOREEN G. LEOPOLD, Department of Chemistry, University of Minnesota, Minneapolis, MN 55455. RF15 15 min 5:21 PHOTODISSOCIATION SPECTROSCOPY AND DISSOCIATION DYNAMICS OF TiO (CO ) MANORI PERERA RICARDO B. METZ , Department of Chemistry, University of Massachusetts Amherst , Amherst, MA. 67 RG. ASTRONOMICAL SPECIES AND PROCESSES THURSDAY, JUNE 25, 2009 – 1:30 PM Room: 170 MATH ANNEX Chair: DeWAYNE HALFEN, University of Arizona, Tucson, Arizona RG01 15 min 1:30 HIGH-SENSITIVITY, BROADBAND SPECTRAL LINE SURVEYS OF STAR FORMING REGIONS WITH THE CSO SUSANNA L. WIDICUS WEAVER, Department of Chemistry, Emory University, Atlanta, GA 30322; MATTHEW C. SUMNER, FRANK RICE, JONAS ZMUIDZINAS, Division of Physics, Mathematics, and Astronomy, California Institute of Technology, Pasadena, CA 91125; GEOFFREY A. BLAKE, Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125. RG02 CURRENT RESULTS FROM A SPECTRAL-LINE SURVEY OF SGR B2(N) 15 min 1:47 D. T. HALFEN and L. M. ZIURYS, Department of Chemistry, Department of Astronomy, and Steward Observatory, University of Arizona, Tucson, AZ 85721. RG03 15 min 2:04 HCO IN THE HELIX NEBULA L. N. ZACK and L. M. ZIURYS, Department of Chemistry, Department of Astronomy, and Steward Observatory, University of Arizona, Tucson, AZ, 85721. RG04 THE GBT PRIMOS PROJECT - SCIENCE, STATUS, AND SUSPICIONS 15 min 2:21 ANTHONY J. REMIJAN, National Radio Astronomy Observatory, 520 Edgemont Road, Charlottesville, VA 22903; J. M. HOLLIS, NASA’s Goddard Space Flight Center, Computational and Information Sciences and Technology Office, Greenbelt, MD, 20771; P. R. JEWELL, National Radio Astronomy Observatory, 520 Edgemont Road, Charlottesville, VA 22903; F. J. LOVAS, NIST, Optical Technology Division, 100 Bureau Drive, Gaithersburg, MD 20899. RG05 15 min 2:38 SEARCH FOR HOT AND BRIGHT STARS FOR H SPECTROSCOPY NEAR THE GALACTIC CENTER TAKESHI OKA, Department of Astronomy and Astrophysics and Department of Chemistry, University of Chicago, Chicago, IL 60637; T. R. GEBALLE, Gemini Observatory, Hilo, HI 96720. RG06 10 min 2:55 THE ORIGINS OF ETHYL CYANIDE AND DIMETHYL ETHER IN THE INTERSTELLAR MEDIUM DOUGLAS N. FRIEDEL, Department of Astronomy, University of Illinois, 1002 W. Green St., Urbana, IL 61801; SUSANNA L. WIDICUS WEAVER, Department of Chemistry, Emory University, 1515 Dickey Drive, Atlanta, GA 30322. 68 Intermission RG07 NEW LABORATORY MEASUREMENTS OF RHOMBOIDAL SiC 15 min 3:20 CARL A. GOTTLIEB and PATRICK THADDEUS, Harvard-Smithsonian Center for Astrophysics, 60 Garden St., Cambridge, MA 02138, and School of Engineering & Applied Sciences, Harvard University, 29 Oxford St., Cambridge, MA 02138. RG08 THE ROTATIONAL SPECTRA OF THE SILICON ISOTOPIC SPECIES OF SiCC 10 min 3:37 DAMIAN L. KOKKIN, CARL A. GOTTLIEB, MICHAEL. C. McCARTHY, and PATRICK THADDEUS, Harvard-Smithsonian Center for Astrophysics, 60 Garden St., Cambridge, MA 02138, and School of Engineering & Applied Sciences, Harvard University, 29 Oxford St., Cambridge, MA 02138; and SANDRA BRÜNKEN, Laboratoire de Chimie Physique Mol éculaire, École Polytechnique Fédérale de Lausanne, Station 6, CH-1015 Lausanne, Switzerland. RG09 15 min 3:49 ELECTRONIC SPECTROSCOPY OF COMBUSTION GENERATED SMALL PAH’s BY R2PI FROM 207 to 320 nm Y. CARPENTIER, T. PINO and PH. BRÉCHIGNAC, Laboratoire de Photophysique Mol éculairea , CNRS, Bât 210, Université Paris-Sud, F91405 Orsay Cedex, France. a Member of the Fédération de Recherche Lumière Matière RG10 15 min 4:06 ELECTRONIC SPECTROSCOPY OF VUV IRRADIATED PAH CONTAINING INTERSTELLAR WATER ICE J. BOUWMAN and H. LINNARTZ, Raymond and Beverly Sackler Laboratory for Astrophysics, Leiden Observatory, Leiden University, N. Bohrweg 2, 2333CA Leiden; L. J. ALLAMANDOLA, NASA-Ames Research Center, Space Science Division, Moffet Field, CA 94035. RG11 15 min 4:23 RESULTS FROM VUV SPECTROSCOPY OF NEUTRAL DIAMONDOID MOLECULES AND IR SPECTROSCOPY OF THE CATIONIC SPECIES OLIVIER PIRALI, SÉVERINE BOYÉ-PERONNE and STÉPHANE DOUIN, Laboratoire de Photophysique Moléculaire, Université Paris-Sud, 91405 Orsay Cedex, France; HECTOR ALVARO GALUE and JOS OOMENS, FOM-Institute for Plasma Physics Rijnhuizen, NL 3430 BE Nieuwegein, The Netherlands; GUSTAVO GARCIA, LAURENT NAHON and MICHEL VERVLOET, Synchrotron SOLEIL, L’Orme des Merisiers Saint-Aubin, 91192 Gif-sur-Yvette, France. RG12 15 min 4:40 SUBMILLIMETER-WAVE OBSERVATIONS OF C N IN AN EXTENDED NEGATIVE GLOW DISCHARGE T. AMANO, Department of Chemistry, University of Waterloo, Waterloo, ON, Canada N2L 3G1. 69 RG13 SHOCK FORMATION OF INITIAL MOLECULAR ICE MANTLES 15 min 4:57 GEORGE E. HASSEL, Department of Physics, The Ohio State University, Columbus, OH 43210; ERIC HERBST, Departments of Physics, Astronomy, & Chemistry, The Ohio State University, Columbus, OH 43210; EDWIN A. BERGIN, Department of Astronomy, University of Michigan, 825 Dennison Building, Ann Arbor, MI 48109. RG14 15 min 5:14 AB INITIO QUANTUM CALCULATIONS OF REACTIONS IN ASTROPHYSICAL ICES: ACETALDEHYDE AND ACETONE WITH AMMONIA L. CHEN and D. E. WOON, Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana IL 61801. RG15 15 min 5:31 MICROWAVE SPECTRA OF METHYL FORMATE ISOTOPOMER (HCOO CH ) HARUKA TACHI, KAORI KOBAYASHI, SHOZO TSUNEKAWA, , Department of Physics, University of Toyama, 3190 Gofuku, Toyama, 930-8555 Japan; MEGUMI KUWANO, MASAHARU FUJITAKE, NOBUKIMI OHASHI, Kanazawa University, Japan; NAOTO HAYASHI, and HIROYUKI HIGUCHI, Department of Chemistry, University of Toyama, 3190 Gofuku, Toyama, 930-8555 Japan. RG16 15 min 5:48 CH CH : A 2-STATE FREQUENCY ANALYSIS OF THE TORSIONAL BANDS TORSIONAL SPECTRUM OF AND THE VIBRATIONAL FUNDAMENTAL L. BORVAYEH, N. MOAZZEN-AHMADI, Department of Physics and Astronomy, University of Calgary, Calgary, AB T2N 1N4, CANADA; V.-M. HORNEMAN, Department of Physical Sciences, University of Oulu, PO Box 3000, Fin-90014, Oulu, Finland. 70 RH. MICROWAVE THURSDAY, JUNE 25, 2009 – 1:30 PM Room: 1000 McPHERSON LAB Chair: BRIAN DIAN, Purdue University, West Lafayette, Indiana RH01 15 min 1:30 AN ACOUSTIC DEMONSTRATION MODEL FOR CW AND PULSED SPECTROSOCOPY EXPERIMENTS TORBEN STARCK, HEINRICH MÄDER, Institut für Physikalische Chemie, Universität Kiel, Olshausenstr. 40, D-24098 Kiel, Germany; TREVOR TRUEMAN, and WOLFGANG J ÄGER, Department of Chemistry, University of Alberta, Edmonton, AB, Canada T6G 2G2. RH02 15 min 1:47 WHERE MILLIMETER WAVE SPECTRA ARE SENSITIVE TO SMALL ELECTRIC FIELDS: HIGH RYDBERG STATES OF XENON AND THEIR HYPERFINE STRUCTURES MARTIN SCHÄFER, MATTHIAS RAUNHARDT, and FRÉDÉRIC MERKT, ETH Zürich, Laboratorium f ür Physikalische Chemie, Wolfgang-Pauli-Strasse 10, 8093 Z ürich, Switzerland. RH03 15 min 2:04 BREAKDOWN OF THE REDUCTION OF THE ROVIBRATIONAL HAMILTONIAN : THE CASE OF S O F L. MARGULÈS, J. DEMAISON, Laboratoire PhLAM, CNRS UMR 8523, Universit é de Lille 1, Bat. P5, 59655 Villeneuve d’Ascq Cedex, France.; A. PERRIN, Laboratoire Inter Universitaire des Systemes Atmosphériques, CNRS UMR 7583, Université Paris 12, 61 Av du General de Gaulle, 94010 Cr éteil Cedex France.; I. MERKE, ; Institute für Physikalische Chemie, RWTH Aachen, 52056 Aachen, Germany; H. WILLNER, Anorganische Chemie, FB C, Universit ät-GH Wuppertal, 42097 Wuppertal, Germany; M. ROTGER, Groupe de Spectromtrie Moléculaire et Atmosphrique, CNRS UMR 6089, Moulin de la Housse, BP 1039, Cases 16-17, 51687 Reims Cedex 2, France; and V. BOUDON, Institut Carnot de Bourgogne, UMR CNRS 5209, 9 avenue Alain Savary, BP 47870, 21078 Dijon Cedex, France. RH04 10 min 2:21 EXTENDED TOWNES-DAILEY ANALYSIS OF THE NUCLEAR QUADRUPOLE COUPLING TENSOR STEWART E. NOVICK, Department of Chemistry, Wesleyan University, Middletown, CT 06459. RH05 15 min 2:33 A NEW PROGRAM FOR NON-EQUIVALENT TWO-TOP INTERNAL ROTORS WITH A C FRAME I. KLEINER, Laboratoire Interuniversitaire des Syst èmes Atmosphériques, CNRS et Universités Paris 7 et Paris 12, 61 av. Général de Gaulle, 94010, Créteil, France; J. T. HOUGEN, Optical Technology Division, National Institute for Standards and Technology, Gaithersburg, MD 20899-8441, USA. RH06 15 min 2:50 PROTON DONOR/ACCEPTOR PROPENSITIES OF AMMONIA: ROTATIONAL STUDIES OF ITS MOLECULAR COMPLEXES WITH ORGANIC MOLECULES BARBARA M. GIULIANO, ASSIMO MARIS, SONIA MELANDRI, LAURA B. FAVERO, LUCA EVANGELISTI and WALTHER CAMINATI, Dipartimento di Chimica ”G. Ciamician” dell’Universit à, Via Selmi 2, I-40126 Bologna, Italy. 71 Intermission RH07 15 min 3:30 DESIGN AND CHEMICAL APPLICATION OF CHIRPED-PULSE MILLIMETER-WAVE SPECTROSCOPY G. B. PARK, A. H. STEEVES, K. KUYANOV-PROZUMENT, A. P. COLOMBO, and R. W. FIELD, Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139; J. L. NEILL and B. H. PATE, Department of Chemistry, University of Virginia, Charlottesville, VA 22904. RH08 15 min 3:47 BROADBAND CHIRPED-PULSE FOURIER-TRANSFORM MICROWAVE SPECTROSCOPIC INVESTIGATION OF THE STRUCTURES OF THREE DIETHYLSILANE CONFORMERS AMANDA L. STEBER, DANIEL A. OBENCHAIN, REBECCA A. PEEBLES, and SEAN A. PEEBLES, Department of Chemistry, Eastern Illinois University, 600 Lincoln Avenue, Charleston, IL 61920; JUSTIN L. NEILL, MATT T. MUCKLE, and BROOKS H. PATE, Department of Chemistry, University of Virginia, Charlottesville, VA 22904; GAMIL A. GUIRGIS, Department of Chemistry and Biochemistry, The College of Charleston, Charleston, SC 29424. RH09 15 min 4:04 THE PURE ROTATIONAL SPECTRA OF CrS SULFIDES (X ): CONTINUED STUDIES OF THE 3d TRANSITION METAL R. L. PULLIAM, A. J. HIGGINS, and L. M. ZIURYS, Department of Chemistry, Department of Astronomy, Steward Observatory, University of Arizona, Tucson, AZ 85721. RH10 SUBMILLIMETER SPECTROSCOPY OF ZnOH SPECIES (X A ): 15 min 4:21 STRUCTURE AND BONDING IN 3d HYDROXIDE L. N. ZACK and L. M. ZIURYS, Department of Chemistry, Department of Astronomy, and Steward Observatory, University of Arizona, Tucson, AZ, 85721. RH11 MICROWAVE SPECTRA AND STRUCTURES OF H S-CuCl AND H S-AgCl. 15 min 4:38 N. R. WALKER, D. WHEATLEY AND A. C. LEGON, School of Chemistry, University of Bristol, Bristol, BS8 1TS, U.K.. RH12 MICROWAVE SPECTROSCOPY OF THE HEAVY-ATOM CARBENE ANALOGS: HSiI and DSiI 15 min 4:55 LU KANG, Department of Natural Sciences, Union College, Barbourville, KY 40906; MOHAMMED A. GHARAIBEH, DENNIS J. CLOUTHIER, Department of Chemistry, University of Kentucky, Lexington, KY 40506; STEWART E. NOVICK, Department of Chemistry, Wesleyan University, Middletown, CT 06459. 72 RH13 15 min 5:12 SPECTROSCOPIC CHARACTERIZATION OF HIGHLY ENERGETIC ISOFULMINIC ACID, HONC, BY EXPERIMENTAL AND THEORETICAL APPROACHES M. C. MCCARTHY, P. THADDEUS, Harvard-Smithsonian Center for Astrophysics, 60 Garden St., Cambridge, MA 02138, and School of Engineering and Applied Sciences, Harvard University, 29 Oxford St., Cambridge, MA 02138; MIRJANA MLADENOVIC AND MARIUS LEWERENZ, Universit é Paris-Est, Laboratoire Modélisation et Simulation Multi Echelle, MSME FRE3160 CNRS, 5 bd Descartes, 77454 Marne la Vallée, France. RH14 15 min 5:29 ASSIGNMENT OF THE MM- AND SMM-WAVE ROTATIONAL SPECTRA OF RARE ISOTOPOLOGUES OF CYANAMIDE AND THE MOLECULAR GEOMETRY OF NH CN ADAM KRASNICKI, ZBIGNIEW KISIEL, Institute of Physics, Polish Academy of Sciences, Al. Lotnik ów 32/46, 02-668 Warszawa, Poland; BRENDA P. WINNEWISSER, MANFRED WINNEWISSER, Department of Physics, The Ohio State University, Columbus, OH 43210. 73 RI. ATMOSPHERIC SPECIES THURSDAY, JUNE 25, 2009 – 1:30 PM Room: 1015 McPHERSON LAB Chair: GEOFFREY DUXBURY, University of Strathclyde, Glasgow, Scotland RI01 15 min 1:30 HITRAN2008 EST ARRIV É L. S. ROTHMAN, I. E. GORDON, Harvard-Smithsonian Center for Astrophysics, Atomic and Molecular Physics Division, Cambridge MA 02138-1516, USA. RI02 15 min 1:47 LINE STRENGTH MEASUREMENTS IN THE BAND OF H O Yu. I. BARANOV, Institute of Experimental Meteorology, Lenina 82, Obninsk, Kaluga region 249020, Russia; P. CHELIN, J. ORPHAL, and L. H. COUDERT, LISA, CNRS/Universit és Paris 12 et 7, 61 Avenue du G énéral de Gaulle, 94010 Créteil, France. RI03 15 min 2:04 HALF-WIDTHS, THEIR TEMPERATURE DEPENDENCE, AND LINE SHIFTS FOR THE ROTATION BAND OF H O ROBERT R. GAMACHE AND ANNE L. LARAIA, Department of Environmental, Earth, and Atmospheric Sciences, University of Massachusetts Lowell. RI04 THEORETICAL CALCULATION OF THE N BROADENED HALF-WIDTHS OF H O 15 min 2:21 Q. MA, NASA/Goddard Institute for Space Studies and Department of Applied Physics and Applied methamatics, Columbia University, 2880 Broadway, New York, NY 10025; R. H. TIPPING, Department of Physics and Astronomy, University of Alabama, Tuscaloosa, AL 35487; R. R. GAMACHE, Department of Environmental, Earth and Atmospheric Science, University of Mass. Lowell, Lowell, MA 01854. RI05 15 min 2:38 TEMPERATURE DEPENDENCES OF MECHANISMS RESPONSIBLE FOR THE WATER VAPOR CONTINUUM Q. MA, NASA/Goddard Institute for Space Studies and Department of Applied Physics and Applied methamatics, Columbia University, 2880 Broadway, New York, NY 10025; R. H. TIPPING, Department of Physics and Astronomy, University of Alabama, Tuscaloosa, AL 35487; C. LEFORESTIER, Institute Charles Gerhardt CNRS-5253, CC1501, Université Montpellier II, 34095 Montpellier, France. RI06 15 min 2:55 FIRST ANALYSIS OF THE BAND OF DNO (DEUTERATED NITRIC ACID) IN THE 11 m REGION J.KOUBEK, Institute of Chemical Technology, Department of Analytical Chemistry, Technick á 5,166 28, Praha 6, Czech Republic, and Laboratoire Inter Universitaire des Systemes Atmosph ériques, CNRS, Université Paris 12, 61 Av du General de Gaulle, 94010 Cr éteil Cedex France; A.PERRIN, Laboratoire Inter Universitaire des Systemes Atmosphériques, CNRS, Université Paris 12, 61 Av du General de Gaulle, 94010 Créteil Cedex France; H. BECKERS, H. WILLNER, Anorg. Chemistry, University of Wuppertal, D-42119 Wuppertal, GERMANY. 74 RI07 15 min 3:12 NEW ANALYSIS OF THE BAND OF HDCO (MONODEUTERATED FORMALDEHYDE) IN THE 5.8 m REGION L. GOMEZ, LAboratoire de Dynamique, Interactions et R éactivité (LADIR, CNRS UMR 7075) Université Pierre et Marie Curie - Paris VI ; Case courrier 49, B ât F 74, 4, place Jussieu, 75252 Paris Cedex, France.; A.PERRIN, Laboratoire Inter Universitaire des Systemes Atmosph ériques, CNRS, Université Paris 12, 61 Av du General de Gaulle, 94010 Cr éteil Cedex France; G. C. MELLAU, Justus-Liebig - Universit ät, PhysikalischChemisches Institut, Heinrich-Buff-Ring 58, D-35392 Gießen, Germany. Intermission RI08 HARMONISATION OF GOME, SCIAMACHY AND GOME-2 OZONE CROSS-SECTIONS 15 min 3:45 ANNA SERDYUCHENKO, JOHN P. BURROWS and MARK WEBER, Institut für Umweltphysik, Universität Bremen, Ott-Hahn-Allee 1, D-28359 Bremen, Germany. RI09 15 min 4:02 HIGH-RESOLUTION SPECTROSCOPY AND ANALYSIS OF THE DYAD OF CF V. BOUDON, Institut Carnot de Bourgogne, UMR 5209 CNRS–Universit é de Bourgogne, 9 Av. A. Savary, BP 47870, F-21078 Dijon Cedex, France; A. DOMANSKAYA, Institute of Physics, St. Petersburg University, 198504 St. Petersburg, Russia; C. MAUL, Institut f ür Physikalische und Theoretische Chemie der Technischen Universität Braunschweig, D-38106 Braunschweig, Germany; R. GEORGES, Institut de Physique de Rennes, UMR 6251 CNRS–Universit de Rennes 1, 263 Av. G énéral Leclerc, F-35042 Rennes Cedex, France; J. MITCHELL, University of Arkansas, 226 Physics Building, Fayetteville AR 72701, USA. RI10 15 min 4:19 NEW HIGH-RESOLUTION ABSORPTION CROSS-SECTION MEASUREMENTS OF HCFC-142B IN THE MID-IR KARINE LE BRIS, Department of Physics, St. Francis Xavier University, Antigonish, NS, Canada, B2G2W5; KIMBERLY STRONG, Department of Physics, University of Toronto, Toronto, ON, Canada, M5S1A7; and STELLA MELO, Canadian Space Agency, St. Hubert, QC, Canada, J3Y8Y9. RI11 LINE INTENSITIES OF ISOTOPIC CARBONYL SULFIDE (OCS) AT 2.5 MICROMETER 15 min 4:36 ROBERT A. TOTH, KEEYOON SUNG, LINDA R. BROWN, TIMOTHY J. CRAWFORD, Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109. RI12 cm 15 min 4:53 SPECTRAL REGION OF CO : CONSTRAINED MULTISPECTRUM NONLINEAR LEAST THE 4850 SQUARES FITTING INCLUDING LINE MIXING, SPEED DEPENDENT LINE PROFILES AND FERMI RESONANCE D. CHRIS BENNER, V. MALATHY DEVI, EMILY NUGENT, Department of Physics, College of William and Mary, Box 8795, Williamsburg, VA 23187-8795; LINDA R. BROWN, CHARLES E. MILLER, ROBERT A. TOTH, and KEEYOON SUNG, Jet Propulsion Laboratory a, California Institute of Technology, Pasadena, CA 91109. a The research at the Jet Propulsion laboratory (JPL), California Institute of Technology, was performed under contract with National Aeronautics and Space Administration. 75 RI13 15 min 5:10 MEASUREMENTS OF THE CO 15 m BAND SYSTEM BROADENED BY AIR, N AND CO AT TERRESTRIAL ATMOSPHERIC TEMPERATURES M. A. H. SMITH, Science Directorate, NASA Langley Research Center, Hampton, VA 23681; V. MALATHY DEVI, D. CHRIS BENNER, Department of Physics, The College of William and Mary, Williamsburg, VA 23187; T. A. BLAKE and R. L. SAMS, William R. Wiley Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, WA 99352. RI14 15 min 5:27 LINE POSITIONS, INTENSITIES, SELF- AND N -BROADENING PARAMETERS IN THE BAND OF ETHANE (C H ) CURTIS P. RINSLAND, Science Directorate, NASA Langley Research Center, Hampton, VA 23681; V. MALATHY DEVI, D. CHRIS BENNER, Department of Physics, The College of William and Mary, Williamsburg, VA 23187; ROBERT L. SAMS and THOMAS A. BLAKE, William R. Wiley Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, WA 99352. 76 RJ. THEORY THURSDAY, JUNE 25, 2009 – 1:30 PM Room: 2015 McPHERSON LAB Chair: RUSSELL PITZER, The Ohio State University, Columbus, Ohio RJ01 INVITED TALK 30 min 1:30 THE CALCULATION OF ROTATIONAL ENERGY LEVELS USING TUNNELING HAMILTONIANS JON T. HOUGEN, Optical Technology Division, NIST, Gaithersburg, MD 20899-8441. RJ02 15 min 2:05 LINE SHIFTS IN ROTATIONAL SPECTRA OF POLYATOMIC CHIRAL MOLECULES CAUSED BY THE PARITY VIOLATING ELECTROWEAK INTERACTION J. STOHNER, ZHAW Zürich University for Applied Sciences, ICBC, Reidbach T, CH 8820 W ädenswil, Switzerland, sthj@zhaw.ch.; M. QUACK, ETH Z ürich, Physical Chemistry, CH 8093 Z ürich, Switzerland. RJ03 USING DIFFUSION MONTE CARLO TO PROBE ROTATIONAL EXCITED STATES 15 min 2:22 ANDREW S. PETIT and ANNE B. McCOY, Department of Chemistry, The Ohio State University, Columbus, OH 43210. RJ04 15 min 2:39 PROBING ROTATIONALLY EXCITED STATES OF CH WITH DIFFUSION MONTE CARLO CHARLOTTE E. HINKLE, ANNE B. McCOY, Department of Chemistry, The Ohio State University, Columbus, OH 43210. RJ05 15 min 2:56 ENERGY-LEVEL-CLUSTER RELATED NUCLEAR-SPIN EFFECTS AND SUPER-HYPERFINE SPECTRAL PATTERNS: HOW MOLECULES DO SELF-NMR WILLIAM HARTER, JUSTIN MITCHELL, University of Arkansas, Department of Physics, Fayetteville, AR 72701. RJ06 15 min 3:13 ROVIBRATIONAL PHASE-SPACE SURFACES FOR ANALYSIS OF POLYAD BAND OF CF JUSTIN MITCHELL, WILLIAM HARTER, University of Arkansas, Department of Physics, Fayetteville, AR 72701; VINCENT BOUDON, Institut Carnot de Bourgogne, UMR 5209 CNRS–Universit é de Bourgogne, 9 Av. A. Savary, BP 47870, F-21078 Dijon Cedex, France. Intermission 77 RJ07 15 min 3:45 THE LOW-LYING STATES OF SF SPECIES ( =1–6): INSIGHTS INTO HYPERVALENCY FROM THE RECOUPLED PAIR BONDING MODEL D. E. WOON and T. H. DUNNING, JR., Department of Chemistry, University of Illinois at UrbanaChampaign, Urbana, IL 61801. RJ08 15 min 4:02 UNDERSTANDING THE MOLECULAR PROPERTIES OF ClF ( 1-7) SPECIES: AN APPLICATION OF THE RECOUPLED PAIR BONDING MODEL FOR HYPERVALENT BONDS L. CHEN, D. E. WOON, and T. H. DUNNING, Jr., Department of Chemistry, University of Illinois at UrbanaChampaign, Urbana, IL 61801. RJ09 15 min 4:19 CALCULATION OF GAS-PHASE ELECTRONIC SPECTRA OF TRANSITION-METAL COMPLEXES a JAMES T. MUCKERMAN, Chemistry Department, Brookhaven National Laboratory, Upton, NY 119735000. a This work was performed at Brookhaven National Laboratory and funded under contract DE-AC02-98CH10886 with the U.S. Department of Energy and supported by its Division of Chemical Sciences, Geosciences, and Biosciences, Office of Basic Energy Sciences. The U.S Department of Energy is also gratefully acknowledged for funding under the BES Hydrogen Fuel Initiative. RJ10 15 min 4:36 BALANCED DESCRIPTION OF GROUND-STATE PROPERTIES, VALENCE EXCITATIONS, AND CHARGETRANSFER EXCITATIONS WITH LONG-RANGE CORRECTED DENSITY FUNCTIONALS MARY A. ROHRDANZ, JOHN M. HERBERT, Department of Chemistry, The Ohio State University, Columbus, OH 43210. RJ11 AB INITIO POTENTIAL ENERGY SURFACE FOR THE Xe+OH INTERACTION 15 min 4:53 VIPIN B. SINGH, Department of Physics, U P Autonomous College, Varanasi-221002, India; MICHAEL C. HEAVEN, Emersion Center for Scientific Computation, Emory University, Atlanta GA, USA. RJ12 10 min 5:10 IONS: LOOKING FOR CLARITY IN ACTINIDE ELECTRONIC ELECTRONIC STRUCTURE OF PA STRUCTURE MICHAEL MROZIK, RUSSELL M. PITZER, DEPT. OF CHEMISTRY, THE OHIO STATE UNIVERSITY; BRUCE E. BURSTEN, UNIVERSITY OF TENNESSEE-KNOXVILLE. RJ13 ELECTRONIC STRUCTURE OF N DIMER CATION 10 min 5:22 K. KHISTYAEV, A. I. KRYLOV, AND A. LANDAU, Department of Chemistry, University of Southern California, Los Angeles, CA 90089. 78 FA. THEORY FRIDAY, JUNE 26, 2009 – 8:30 AM Room: 160 MATH ANNEX Chair: VINCENT BOUDON, Université de Bourgogne, Dijon, France FA01 LOCATING MINIMUM ENERGY CROSSING POINTS USING EOM-CC METHODS 15 min 8:30 E. EPIFANOVSKY and A. I. KRYLOV, University of Southern California, Los Angeles, CA 90089. FA02 INTRAMOLECULAR CHARGE TRANSFER STATES IN THE CONDENSED PHASE 15 min 8:47 C. F. WILLIAMS and J. M. HERBERT, Ohio State Chemistry Department, Newman and Wolfrom Lab, 100 W. 18th Avenue Columbus, OH, 43210. FA03 FORMATION OF EXCITED H O STATES BY CHARGE TRANSFER FROM Cs 10 min 9:04 STANISLAV A. DOLGIKH, ANNA I. KRYLOV, Department of Chemistry, University of Southern California, Los Angeles, CA 90007. FA04 RE–OPTIMIZATION OF AN ELECTRON–WATER PSEUDOPOTENTIAL 15 min 9:16 LEIF D. JACOBSON, JOHN M. HERBERT, Department of Chemistry, the Ohio State University, Columbus, OH 43210. FA05 STARK EFFECT AND TORSIONAL MOTION INTERACTION IN BIPHENYL 15 min 9:33 L. H. COUDERT, LISA, UMR 7583 CNRS/Universités Paris 12 et 7, 61 Avenue du G énéral de Gaulle, 94010 Créteil Cedex, France; L. F. PACIOS, Unidad de Quı́mica y Bioquı́mica, Departamento de Biotecnologı́a, ETSI Montes, Universidad Politécnica de Madrid, 28040 Madrid, Spain; and J. ORTIGOSO, Instituto de Estructura de la Materia, CSIC, Serrano 121, 28006 Madrid, Spain. FA06 ETHANE ASYMMETRIC C-H STRETCHING VIBRATIONAL SPECTRA 15 min 9:50 MARIA VILLA, Departamento de Quimica. Universidad Autonoma Metropolitana, Av. San Rafael Atlixco 186, Col Vicentina, Iztapala, Mexico D.F. 09340, MEXICO; MA. LUISA SENENT, Departamento de Astrofisica Molecular e Infrarroja, Instituto de Estructura de la Materia, C.S.I.C., Serrano 113B, Madrid 28006, SPAIN; and DAVID R. HIDALGO, Departamento de Quimica. Universidad Autonoma Metropolitana, Av. San Rafael Atlixco 186, Col Vicentina, Iztapala, Mexico D.F. 09340. Intermission 79 FA07 15 min 10:20 CONFORMATIONAL PROPERTIES, SPECTROSCOPY AND STRUCTURE OF ISATIN-(WATER) CLUSTERS MILIND K. SINGH, D. M. UPADHYA and VIPIN B. SINGH, Department of Physics, U P Autonomous College, Varanasi-221002, India. FA08 Post-deadline Abstract 15 min 10:37 LASER SPECTROSCOPY AND DENSITY FUNCTIONAL STUDY ON NIOBIUM DIMER CATION METIN AYDIN, Department of Chemistry, Faculty of Art and Sciences, Ondokuz Mayis University, 55139, Samsun, Turkey; JOHN R. LOMBARDI , Department of Chemistry and Center for Analysis of Structures and Interfaces (CASI), The City College of New York (CCNY), New York, NY10031. FA09 Post-deadline Abstract 15 min 10:54 SILYL FLUORIDE: LAMB-DIP SPECTRA AND EQUILIBRIUM STRUCTURE CRISTINA PUZZARINI, GABRIELE CAZZOLI, Dipartimento di Chimica ”G. Ciamician”, Universit à di Bologna, I-40126 Bologna, Italy; J ÜRGEN GAUSS, Institut für Physikalische Chemie, Universität Mainz, D-55099 Mainz, Germany. FA10 Post-deadline Abstract 15 min 11:11 INVESTIGATION OF COUPLING BETWEEN OH STRETCHING AND H O OUT-OF-PLANE BENDING MODES IN OH-H O PESIA SOLOVEICHIK, BRIDGET A. O’DONNELL, MARSHA I. LESTER, Department of Chemistry, University of Pennsylvania, Philadelphia, PA 19104; ANNE B. McCOY, Department of Chemistry, The Ohio State University, Columbus, OH 43210. FA11 Post-deadline Abstract 15 min 11:28 STUDYING THE STEREOCHEMISTRY OF NAPROXEN USING ROTATIONALLY RESOLVED ELECTRONIC SPECTROSCOPY. a JUSTIN W. YOUNG, LEONARDO ALVAREZ-VALTIERRA, and DAVID W. PRATT, Department of Chemistry, University of Pittsburgh, PA 15260. a Work supported by NSF (CHE-0615755) 80 FB. DYNAMICS FRIDAY, JUNE 26, 2009 – 8:30 AM Room: 170 MATH ANNEX Chair: JINGSONG ZHANG, University of California, Riverside, California FB01 QUANTUM SOLVATION OF CO BY H ATOMS: FROM ONSET TO NANODROPLET 15 min 8:30 HUI LI, PIERRE-NICHOLAS ROY and ROBERT J. LE ROY, Guelph-Waterloo Centre for Graduate Work in Chemistry and Biochemistry, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada. FB02 ULTRAFAST HYDROGEN TRANSFER IN N,N-DIMETHYLISOPROPYL AMINE CLUSTERS 15 min 8:47 SANGHAMITRA DEB, MICHAEL P. MINITTI, PETER M. WEBER, Department of Chemistry, Brown University, Providence, Rhode Island 02912. FB03 DYNAMICS OF VIBRATIONALLY EXCITED PHENOL-CO 15 min 9:04 AMANDA S. CASE, Y. HEIDI YOON, F. FLEMING CRIM, The University of Wisconsin - Madison Department of Chemistry, 1101 University Avenue, Madison, WI 53705. FB04 15 min 9:21 NATURE OF TORSION-INVERSION COUPLING IN CH NH , CH OH AND CH CH RAM S BHATTA, AMY GAO AND DAVID S PERRY, Department of Chemistry, The University of Akron, OH 44325-3601. Intermission FB05 15 min 10:00 ENERGY AND RATE DETERMINATIONS TO ACTIVATE THE C-C ! -BOND OF ACETONE BY GASEOUS VANESSA A. CASTLEBERRY, S. JASON DEE, OTSMAR J. VILLARROEL, IVANNA E. LABOREN, SARAH E. FREY and DARRIN J. BELLERT, Department of Chemistry and Biochemistry, Baylor University, Waco, Texas, 76798. FB06 BROADENING THE HORIZONS OF NONLINEAR OPTICS BY NOSE 15 min 10:17 NATHAN J. BEGUE and GARTH J. SIMPSON, Department of Chemistry, Purdue University, Lafayette, Indiana 47907.. 81 FB07 10 min 10:34 FLUORESCENCE IMAGING: A VERSATILE METHOD TO STUDY PHOTODISSOCIATION DYNAMICS K. M. CHEN, K. C. CHEN, Department of Chemistry, National Sun Yat-sen University, Kaohsiung, Taiwan, Republic of China. FB08 Post-deadline Abstract 15 min 10:46 SPECTROSCOPIC STRUCTURAL INVESTIGATIONS OF CHARGE-TRANSFER COMPLEXES OF n-DONORS AND SIGMA- AND PI-ACCEPTORS EL-METWALLY NOUR, SIHAM Y. ALQARADAWI, Department of Chemistry and Earth Sciences, Qatar University, P.O.Box 2713 Doha, Qatar. FB09 Post-deadline Abstract 15 min 11:03 DIRECT INFRARED ABSORPTION SPECTROSCOPY OF BENZENE CLUSTERS VIJAYANAND CHANDRASEKARAN, Institut de Physique de Rennes, Equipe Astrochimie Exprimentale,Bat.11C, Campus de Beaulieu, Universit de Rennes1, 35042 Rennes Cedex, France; L.BIENNIER, Institut de Physique de Rennes, Equipe Astrochimie Exprimentale,Bat.11C, Campus de Beaulieu, Universit de Rennes1, 35042 Rennes Cedex, France; R.GEORGES, Institut de Physique de Rennes, Equipe Astrochimie Exprimentale,Bat.11C, Campus de Beaulieu, Universit de Rennes1, 35042 Rennes Cedex, France; E.ARUNAN, Department of Inorganic and Physical Chemistry, Indian Institute of Science,Bangalore, India; K.P.J.REDDY, Department of Aerospace Engineering, Indian Institute of Science,Bangalore, India. FB10 Post-deadline Abstract 15 min 11:20 CALCULATED DEPENDENCE OF VIBRATIONAL BAND FREQUENCIES OF SINGLE-WALLED CARBON NANOTUBES ON DIAMETER METIN AYDIN, Department of Chemistry, faculty of Art and Sciences, Ondokuz Mayis University, 55139, Samsun, Turkey; DANIEL L. AKINS, Center for Analysis of Structures and Interfaces (CASI) Department of Chemistry The City College of The City University of New York New York, New York 10031. FB11 Post-deadline Abstract 15 min 11:37 MOLECULAR MECHANISMS IN THE REPAIR OF THE CYCLOBUTANE PYRIMIDINE DIMER ALI A. HASSANALI, DONGPING ZHONG, SHERWIN J. SINGER, Biophysics Program, Department of Physics and Department of Chemistry, The Ohio State University, Columbus, OH 43210. 82 FC. MICROWAVE FRIDAY, JUNE 26, 2009 – 8:30 AM Room: 1000 McPHERSON LAB Chair: STEPHEN COOKE, University of North Texas, Denton, Texas FC01 15 min 8:30 THE PURE ROTATIONAL SPECTRA OF ZnO IN THE EXCITED a STATE L. N. ZACK, R. L. PULLIAM and L. M. ZIURYS, Department of Chemistry, Department of Astronomy, Steward Observatory, University of Arizona, Tucson, AZ 85721. FC02 15 min 8:47 THE PURE ROTATIONAL SPECTRUM OF ZnS (X L. N. ZACK and L. M. ZIURYS, Department of Chemistry, Department of Astronomy, and Steward Observatory, University of Arizona, Tucson, AZ, 85721. FC03 15 min 9:04 MICROWAVE-MICROWAVE DOUBLE RESONANCE INVESTIGATION OF THE H -N O VAN DER WAALS COMPLEX JEN NICOLE LANDRY, WOLFGANG JÄGER, Department of Chemistry, University of Alberta, Edmonton, AB, T6G 2G2, Canada ; YOSHIHIRO SUMIYOSHI AND YASUKI ENDO, Department of Basic Science, Graduate School of Arts and Sciences, The University of Tokyo, Komaba, Meguro-ku, Tokyo 153-8902, Japan. FC04 15 min 9:21 RECOVERY OF LEGACY PAPER SPECTRA AND NEW RESULTS ON THE ROTATIONAL SPECTRUM OF H O HF ZBIGNIEW KISIEL, Institute of Physics, Polish Academy of Sciences, Al. Lotnik ów 32/46, 02-668 Warszawa, Poland; MIKHAIL YU. TRETYAKOV, OLEG L. POLYANSKY, Institute of Applied Physics of RAS, 46 Uljanova Str., 603950 Nizhny Novgorod, Russia. FC05 THE PURE ROTATIONAL SPECTRUM OF HPS (X̃ A ): 15 min 9:38 THE THIRD ROW ANALOG OF HNO D. T. HALFEN, Department of Chemistry, Department of Astronomy, and Steward Observatory, University of Arizona, Tucson, AZ 85721; D. J. CLOUTHIER, Department of Chemistry, University of Kentucky, Lexington, KY 40506; and L. M. ZIURYS, Department of Chemistry, Department of Astronomy, and Steward Observatory, University of Arizona, Tucson, AZ 85721. Intermission 83 FC06 PECULIAR TRAITS OF HSOH IN ITS ROTATIONAL-TORSIONAL SPECTRUM ABOVE 1 THz 15 min 10:15 O. BAUM, M. KOERBER, S. SCHLEMMER, T. F. GIESEN, I. Physikalisches Institut, Universit ät zu Köln, 50937 Köln, Germany; S. N. YURCHENKO, TU Dresden, Institut f ür Physikalische Chemie und Elektrochemie, 01062 Dresden, Germany; W. THIEL, MPI f ür Kohlenforschung, 45470 M ülheim an der Ruhr, Germany; P. JENSEN, FB C – Theoretische Chemie, Bergische Universit ät, 42097 Wuppertal, Germany; K. M. T. YAMADA, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba-West, 305-8569, Japan. FC07 15 min MICROWAVE SPECTRUM AND STRUCTURE DETERMINATION OF THE CCAs RADICAL 10:32 (X ) M.SUN, D. T. HALFEN, Department of Chemistry, Department of Astronomy, and Steward Observatory, University of Arizona, Tucson, AZ 85721; D. J. CLOUTHIER, Department of Chemistry, University of Kentucky, Lexington, KY 40506; and L. M. ZIURYS, Department of Chemistry, Department of Astronomy, and Steward Observatory, University of Arizona, Tucson, AZ 85721. FC08 15 min THE PURE ROTATIONAL SPECTRUM OF SiCl (X ) AND SiCl 10:49 (X ) D. T. HALFEN, M. SUN, and L. M. ZIURYS, Department of Chemistry, Department of Astronomy, and Steward Observatory, University of Arizona, Tucson, AZ 85721. FC09 Post-deadline Abstract 15 min 11:06 OPTICAL EMISSION STUDIES OF NEW BAND SYSTEM OF SILICON DIMER RAM GOPAL, K.S.OJHA and S.C.SINGH, Laboratory of Laser Spectroscopy and Nanomaterials, Department of Physics, University of Allahabad, ALLAHABAD - 211002, INDIA. FC10 Post-deadline Abstract 15 min 11:23 STRUCTURAL STUDY OF POLAR LIQUIDS THROUGH DIELECTRIC STUDY USING TIME DOMAIN REFLECTOMETERY SURESH C.MEHROTRA, Department of Computer Science & Information Technology, Dr. Babasaheb Ambedkar Marathwada University, Aurangabad 431 004.India. FC11 Post-deadline Abstract 15 min 11:40 THE PURE ROTATIONAL SPECTRUM OF TIS (X ) IN ALL THREE SPIN COMPONENTS R. L. PULLIAM, and L. M. ZIURYS, Department of Chemistry, Department of Astronomy, Steward Observatory, University of Arizona, Tucson, AZ 85721. FC12 Post-deadline Abstract ABSOLUTE O 15 min 11:57 NMR SCALE: A JOINT ROTATIONAL-SPECTROSCOPY AND QUANTUM-CHEMISTRY STUDY CRISTINA PUZZARINI, GABRIELE CAZZOLI, Dipartimento di Chimica ”G. Ciamician”, Universit à di Bologna, I-40126 Bologna, Italy; MICHAEL E. HARDING, J ÜRGEN GAUSS, Institut für Physikalische Chemie, Universität Mainz, D-55099 Mainz, Germany. 84 FD. MINI-SYMPOSIUM: CAVITY ENHANCED SPECTROSCOPY FRIDAY, JUNE 26, 2009 – 8:30 AM Room: 1015 McPHERSON LAB Chair: ANDREW ORR-EWING, University of Bristol, Bristol, United Kingdom FD01 INVITED TALK CAVITY-ENHANCED OPTICAL FREQUENCY COMB SPECTROSCOPY 30 min 8:30 JUN YE, MICHAEL J. THORPE, FLORIAN ADLER, and KEVIN C. COSSEL, JILA, NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY AND UNIVERSITY OF COLORADO, BOULDER, CO 803090440. FD02 10 min 9:05 PSEUDO-RANDOM AMPLITUDE OR TONE BURST MODULATION COMBINED WITH CAVITY-ENHANCED DETECTION CHRIS HOVDE, Southwest Sciences Ohio Operations, Cincinnati OH 45244 ; STEVE M. MASSICK and DAVID S. BOMSE, Southwest Sciences, Santa Fe NM 87505. FD03 15 min 9:17 THE APPLICATION OF HIGH-REPETITION-RATE CAVITY RINGDOWN TECHNIQUES TO INFRARED SPECTROSCOPY BRIAN M. SILLER, and BENJAMIN J. McCALL, Department of Chemistry, University of Illinois, Urbana, IL 61801. FD04 15 min 9:34 AN OFF AXIS CAVITY ENHANCED ABSORPTION SPECTROMETER AND A RAPID SCAN SPECTROMETER WITH A ROOM-TEMPERATURE EXTERNAL CAVITY QUANTUM CASCADE LASER XUNCHEN LIU, CHEOLHWA KANG, and YUNJIE XU , Department of Chemistry, University of Alberta, Edmonton, Canada. FD05 LONG TERM STABILITY IN CW-CRDS EXPERIMENTS 15 min 9:51 HAIFENG HUANG, Department of Chemistry, University of Virginia, Charlottesville VA, 22904-4319; KEVIN K. LEHMANN,. Intermission FD06 15 min 10:20 THE INFLUENCE OF FREE-RUNNING FP-QCL FREQUENCY JITTER ON CAVITY RINGDOWN SPECTROSCOPY OF C BRIAN E. BRUMFIELD, JACOB T. STEWART, Department of Chemistry, University of Illinois at UrbanaChampaign, Urbana, IL 61801; MATTHEW D. ESCARRA, CLAIRE F. GMACHL, Department of Electrical Engineering, Princeton University, Princeton Institute for the Science and Technology of Materials, Princeton, NJ 08544; BENJAMIN J. McCALL, Departments of Chemistry and Astronomy, University of Illinois at Urbana-Champaign, Urbana, IL 61801. 85 FD07 ANYTHING BUT TWO MIRRORS: CRD IN WAVEGUIDE CAVITIES. 15 min 10:37 JACK BARNES, KLAUS BESCHERER, STEPHEN BROWN, CATHLEEN M. CRUDDEN, JESSICA LITMAN, HANS-PETER LOOCK, RICHARD D. OLESCHUK, and HELEN WAECHTER, Queen‘s University, Dept. of Chemistry, Kingston, ON, K7L 3N6, Canada. FD08 15 min 10:54 RAYLEIGH SCATTERING CROSS SECTION MEASUREMENTS WITH A THREE MIRROR RING CAVITY DOUGLAS S. KURAMOTO, and RICHARD N. ZARE, Department of Chemistry, Stanford University, Stanford, CA 94305; ALEXANDER A. KACHANOV, Skymoon Ventures, Santa Clara, CA 95054. FD09 15 min 11:11 CAVITY ENHANCED ABSORPTION SPECTROSCOPY USING A BROADBAND PRISM CAVITY AND A SUPERCONTINUUM SOURCE PAUL S. JOHNSTON, Department of Chemistry, University of Virginia, Charlottesville VA, 22904-4319; KEVIN K. LEHMANN,. FD10 AMPLIFIED FIBER-LOOP RINGDOWN SPECTROSCOPY 10 min 11:28 JESSICA LITMAN, JACK BARNES and HANS-PETER LOOCK, Department of Chemistry, Queen‘s University, Kingston, Ontario, Canada. 86 MA. PLENARY SESSION MONDAY, JUNE 22, 2009 – 8:45 AM Room: AUDITORIUM, INDEPENDENCE HALL Chair: JAMES BEATTY, The Ohio State University, Columbus, Ohio Welcome Caroline C. Whitacre, Vice President for Research The Ohio State University 8:45 MA01 40 min 9:00 HELIUM DROPLETS AS NANO-CRYOSTATS FOR MOLECULAR SPECTROSCOPY: AGGREGATION, STATE SELECTION AND ELECTRON SPIN RESONANCE WOLFGANG E. ERNST, Institute of Experimental Physics, Graz University of Technology, Petersgasse 16, A-8010 Graz, Austria. Droplets of about helium atoms generated in a supersonic expansion, represent a nanometer-sized superfluid medium of 0.4 K temperature and can be doped with one or several atoms or molecules that may form complexes in this cold environment. Using two-laser excitation schemes, we were able to identify the alkali trimers K , Rb , K Rb and KRb in their lowest quartet states formed on helium droplets loaded with potassium and rubidium atoms a and assign several excited states that underlie both Jahn-Teller and spin-orbit coupling b. As helium provides a gentle and only weakly perturbing matrix, it appeared desirable to look for ways to measure fine and hyperfine structure directly in the microwave or radiofrequency regime. In preparation for experiments involving optical detection of electron spin transitions in cold molecules, we studied the electronic spin relaxation in alkali atoms and molecules that reside on the surface of a droplet. Measurements of the circular dichroism in the presence of a magnetic field showed that the populations of Zeeman sublevels in alkali atoms are not thermalized c, while for dimers and trimers a temperature of 0.4 K was found, implicitly providing a first determination of the droplets surface temperature d. Optical detection of spin resonance is achieved in an optical pump-probe experiment with the electron spin transition induced in a microwave cavity in a magnetic field between the pump and probe regions. With the pump laser depleting a particular spin state by desorption of the species from the droplet beam or by optical pumping e, the probe laser detects the successful spin flip induced by the microwave field. Examples will be presented showing up to 50 Rabi cycles of an electron spin transition on an alkali doped helium droplet during the flight time of 57 s through the cavity. a J. Nagl, G. Auböck, A. W. Hauser, O. Allard, C. Callegari, and W. E. Ernst, Phys. Rev. Lett. 100, 063001(2008). Auböck, J. Nagl, C. Callegari, and W. E. Ernst, J. Chem. Phys. 129, 114501(2008). c J. Nagl,G. Auböck, C. Callegari, and W. E. Ernst, Phys. Rev. Lett. 98, 075301 (2007). d G. Auböck, J. Nagl, C. Callegari, and W. E. Ernst, J. Phys. Chem. A 111, 7404(2007). e G. Auböck, J. Nagl, C. Callegari, and W. E. Ernst, Phys. Rev. Lett. 101, 035301(2008). b G. 87 MA02 40 min 9:45 ANION SLOW ELECTRON VELOCITY-MAP IMAGING (SEVI): APPLICATIONS TO SPECTROSCOPY AND DYNAMICS DANIEL M. NEUMARK, Department of Chemistry, University of California, Berkeley, CA 94720. The principles and appliciations of anion slow electron velocity-map imaging (SEVI) are discussed. SEVI is a variant of photoelectron (PE) imaging in which mass-selected anions are photodetached at a set of wavelengths using a tunable laser source. The resulting photoelectrons are collected via velocity-map imaging (VMI) using relatively low extraction voltages, with the goal of selectively detecting slow electrons with high efficiency and enlarging their image on the detector. This technique offers photoelectron energy resolution of a few cm , comparable to that of anion zero electron kinetic energy (ZEKE) spectroscopy, while retaining much of the versatility of conventional PE spectroscopy. The capability of SEVI is demonstrated with the study of the vibronic structure of various heteroatom-doped carbon species (C H, C O, C S and C N) as well as the van der Waals rare-gas oxide (RgO) clusters. The application of SEVI to the study of chemical reaction dynamics by the high-resolution mapping of bimolecular reactive potential energy surfaces is also discussed. Photodetachment of Cl H and Cl CH anions probes the shallow well at the entrance of the Cl+H and Cl+CH reactive surfaces, while SEVI of the F H and F H anions probes transition state structure in the F+H and F+CH reactions. Intermission RAO AWARDS Presentation of Awards by Brenda Winnewisser, Ohio State University 10:50 2008 Rao Award Winners Frank Filsinger, Max-Planck Jen Nicole Landry, University of Alberta Fumie Xe Sunahori, University of Kentucky COBLENTZ AWARD Presentation of Award by Andre Sommer, Miami University 11:05 88 MA03 Coblentz Society Award Lecture 40 min 11:10 MOLECULAR SPECTROSCOPY: THE KEY TO UNDERSTANDING THE INTERSTELLAR MEDIUM BENJAMIN J. McCALL, Departments of Chemistry, Astronomy, and Physics, University of Illinois at Urbana-Champaign, Urbana, IL 61801. Ever since Newton first dispersed sunlight with a prism and coined the term spectrum, the field of spectroscopy has been intimately coupled with astrophysics. The first astronomical molecular spectra were obtained nearly 70 years ago, but it is only in the past few decades that molecular astronomy (and “astrochemistry”) has come to the forefront. There are now roughly 150 known interstellar molecules, and molecular spectroscopy has become the key to understanding the physical conditions, chemical nature, and evolutionary status of interstellar clouds and star-forming regions. Our group at Illinois is working to further our understanding of the interstellar medium through an interdisciplinary program of astronomical observations and laboratory spectroscopy. I will present an overview of our group’s work on the simplest polyatomic molecule (H ), which is the cornerstone of interstellar chemistry and a powerful probe of interstellar conditions. Our astronomical spectroscopy of H has revealed a surprisingly large ionization rate in diffuse clouds, as well as a puzzling non-thermal ortho:para-H ratio. In the laboratory, we have utilized infrared spectroscopy to enable detailed studies of the electron recombination of H and the reaction , which is the most common bimolecular reaction in the universe. I will also discuss our group’s development of a fast ion beam spectrometer that will be capable of high-sensitivity and high-precision spectroscopy of a wide range of astrophysically important molecular ions, and our efforts to extend the tools of high resolution spectroscopy to the large, highly symmetric, and astrophysically interesting molecule C . 89 MF. DYNAMICS MONDAY, JUNE 22, 2009 – 1:30 PM Room: 160 MATH ANNEX Chair: BERN KOHLER, The Ohio State University, Columbus, Ohio MF01 15 min 1:30 VIBRATIONAL MEDIATION OF PHOTOISOMERIZATION IN THE CONDENSED PHASE: TRANS-STILBENE KRISTIN A. BRINEY, DAVID S. BOUCHER, ADAM D. DUNKELBERGER, LESLIE V. HERMAN, F. FLEMING CRIM, The University of Wisconsin - Madison Department of Chemistry, 1101 University Avenue, Madison, WI 53705. We have shown previously that selective vibrational excitation of reactants can lead to bond-selective and mode-selective control of gas-phase reactions such as the dissociation of water and hydrogen abstraction from methane isotopologues. Our present work seeks to extend this vibrational control to the solution phase, exploring the effect of vibrational excitation on the photoisomerization of stilbene. Stilbene exhibits ultrafast cis-trans isomerization as well as photoinduced ring closing, making it an excellent model for more complex systems with potential molecular electronics applications. We present the results of the first vibrationally mediated photoisomerization experiments, successfully introducing an infrared excitation pulse to a traditional electronic transient absorption experiment. Our results show that vibrational excitation appears to have little effect on the dynamics of the trans-stilbene excited state. MF02 ULTRAFAST STRUCTURAL DYNAMICS OF TRANS-STILBENE 10 min 1:47 JIE BAO, PETER WEBER, Chemistry Department, Brown University, Providence, RI 02912. Structural changes upon excitation of trans-stilbene to its lowest electronically excited states are well documented. However, reports on its dynamics in higher electronic states are scarce because they are difficult to access. In our experiments, trans-stilbene is pumped to a Rydberg state with a 209 nm femtosecond laser pulse, and then ionized at variable delay times by a 418 nm probe pulse. Photoelectron spectra from the Rydberg levels yield the electron binding energies, which provides a measure of the molecule’s structure. The time dependence of the Rydberg electron binding energy reveals the sub-picosecond structural dynamics of the molecules. MF03 15 min 1:59 EXCITED STATE ISOMERIZATION OF A STILBENE ANALOG: E / Z PHENYLVINYLACETYLENE JOSH J. NEWBY, CHRISTIAN W. MÜLLER, CHING-PING LIU a , HSIUPU D. LEE AND TIMOTHY S. ZWIER, Department of Chemistry, Purdue University, West Lafayette, IN 47907. The excited state isomerization of the E and Z forms of phenylvinylacetylene (PVA, 1-phenyl-1-buten-3-yne) has been studied using ultraviolet population transfer spectroscopy (UVPT). UVPT is a pump-probe experiment, where single isomers are selectively excited and after a wait time, the induced change in population of reactant and product isomers is probed. In these experiments, after initial cooling, an isomer of PVA is selectively excited to vibrational levels in the S electronic state. If the energy supplied by the excitation is above the barrier to isomerization population can be transferred into a product well. Excited molecules are collisionally cooled via supersonic expansion and a new population distribution can be detected downstream via R2PI spectroscopy. From these experiments, product isomerization quantum yields have been determined for both E to Z and Z to E excited state pathways as a function of excess energy above the S origin. a Current Address: Institute of Chemistry, Academia Sinica, Taipei, 11529 Taiwan. 90 MF04 ULTRAFAST STUDIES OF PHOTOISOMERIZATION REACTIONS 15 min 2:16 NICOLE M. DICKSON, JESSICA E. DONEHUE, TERRY L. GUSTAFSON, The Ohio State University, Department of Chemistry, 100 W 18th Avenue, Columbus, OH 43210. Photoisomerization reactions play an important role in biological processes and have potential use in molecular switches. We have recently shown that the photoisomerization reaction for 1,4-diphenyl-1,3-butadiene (DPB) occurs on a fast timescale (less than 50 ps). Further ultrafast studies on the photoisomerization reaction have been conducted on DPB to better understand the nature of the photoisomerization coordinate. Furthermore, the possibility of photoisomerization along a cross-conjugated molecule, 1,3-diphenyl-2,3-butadiene (cc-DPB) has been studied. The possibility of photoisomerization along a branched molecular chain is important for application in molecular switches. MF05 15 min 2:33 CONFORMATIONAL ISOMERIZATION OF bis-(4-HYDROXYPHENYL)METHANE IN A SUPERSONIC JET EXPANSION, PART I: LOW BARRIER POTENTIAL ENERGY SURFACE IN THE STATE. CHIRANTHA P. RODRIGO, CHRISTIAN MÜLLER, WILLIAM H. JAMES III, NATHAN R. PILLSBURY, TIMOTHY S. ZWIER, Department of Chemistry, Purdue University, West Lafayette, IN 47907-2084. The bichromophore bis-(4-hydroxyphenyl)methane, has been studied using single, double and triple resonance laser based spectroscopic methods in a supersonic jet expansion. This molecule consists of two identical chromophores (phenol moieties) linked through a methylene group with torsional flexibility along the two " # bonds. Existence of three conformational isomers in the jet expansion has been established using fluorescence excitation spectroscopy, UV-UV holeburning and fluorescence dip IR spectroscopic methods. – electronic origins of the three conformers are within 25 (0.3 kJ/mol) of one another, with the red most origin at 35184 . Direct experimental determination of the isomerization barriers separating the three conformers were probed using stimulated emission pumping-population transfer spectroscopy. Experimental barriers between conformations are remarkably low, with a highest barrier of no more than 45 (0.54 kJ/mol) from the zero-point level. Quantum chemical calculations carried out using density functional theory (B3LYP/6-311G**) also support the three minimum energy conformations with near-identical stabilities. The calculated potential energy surfaces of the ground state along the phenyl torsional coordinates show that the minimum energy pathways to isomerization lie along the asymmetric phenyl torsional vibrational mode. Furthermore, the predicted torsional energy barriers are comparable in size to the experimentally determined thresholds. 91 MF06 15 min 2:50 CONFORMATIONAL ISOMERIZATION OF bis-(4-HYDROXYPHENYL)METHANE IN A SUPERSONIC JET EXPANSION. PART II: INTERNAL MIXING AND LOW BARRIER POTENTIAL ENERGY SURFACE IN THE STATE. CHRISTIAN W. MÜLLER, CHIRANTHA P. RODRIGO, WILLIAM H. JAMES III, NATHAN R. PILLSBURY and TIMOTHY S. ZWIER, Department of Chemistry, Purdue University, West Lafayette, IN 479072084. The close proximity of two identical ultraviolet chromophores render bis-(4hydroxyphenyl)methane (B4HPM) an interesting case for the study of the dependence of excitonic coupling on the distortion along low-frequency largeamplitude vibrational coordinates, in particular the phenol ring torsional coorOH dinates present in B4HPM. HO We have studied the fluorescence excitation spectrum, the UV-UV holeburning and the spectra and several single vibronic level fluorescence spectra of the transition of all three conformers of B4HPM in a supersonic jet. Excitonic splitting between the two chromophores shifts the second excited state by merely from the origin in both symmetric conformers. The analysis of the dispersed fluorescence spectra of the origins reveals that these levels are internally mixed with nearby vibronic levels, providing a fingerprint of the levels involved in the mixing. The dispersed fluorescence spectra of several low-energy vibronic transitions of a specific conformer were taken under systematic variation of the collision frequency in the region where supersonic jet and laser pulse train intersect. These spectra reveal fluorescence contributions from the other two conformers, thus indicating the presence of low-energy conformational barriers ( – ) in the state of B4HPM. Intermission MF07 15 min 3:30 DYNAMICS OF DANGLING OD-STRETCH AT THE AIR/WATER INTERFACE BY HETERODYNE-DETECTED SFG SPECTROSCOPY I. V. STIOPKIN, C. WEERAMAN, F. SHALHOUT, A. V. BENDERSKII, Department of Chemistry, Wayne State University, Detroit, MI 48202. SFG spectra of dangling OD-stretch at the air/water interface contain information on vibrational dephasing dynamics, ultrafast reorientational molecular motion, and vibrational energy transfer. To better separate these processes we conducted heterodyne-detected SFG experiments to measure real and imaginary contributions of the SFG spectrum of the dangling OD-stretch at the air/D O interface for SSP, PPP, and SPS polarizations. Variations in the temporal profiles of the SFG signals for these three polarizations will be also discussed. MF08 15 min 3:47 PHOTOPHYSICS OF PADDLEWHEEL COMPLEXES INVOLVING MOLYBDENUM OR TUNGSTEN QUADRUPLE BONDS SUPPORTED BY AMIDINATE AND CARBOXYLATE LIGANDS BRIAN G. ALBERDING and MALCOLM H. CHISHOLM, Ohio State University, Department of Chemistry, Columbus, Ohio 43210. Spectroscopic studies of the trans-substituted compounds M (O CCH ) [(N Pr) CR] , where M = Mo or W and R = CCPh have been carried out. These complexes have been shown to possess optically active excited states in both the singlet and triplet manifolds that can be classified as either charge transfer or metal centered in character. The nature of the excited states has been assigned based on steady state absorbance and emission studies and supported by electronic structure calculations. Furthermore, excited state dynamics have been determined from both ns- and fs-transient absorption spectroscopies. 92 MF09 15 min 4:04 THE PHOTOPHYSICAL PROPERTIES OF QUADRUPLY BONDED M ARYLETHYNYLCARBOXYLATE COMPLEXES CARLY R. REED and MALCOLM H. CHISHOLM and CLAUDIA TURRO, Ohio State University, Department of Chemistry, Columbus, Ohio 43210. The incorporation of tolylethynylcarboxylate and anthrylethynylcarboxylate ligands into quadruply bonded dimetal complexes has been achieved. Their photophysical properties have been investigated by fs-transient absorbance, ns-transient absorbance, visible and near-IR emission. These dimetal complexes, where M = molybdenum, exhibit two excited states: one short-lived (fs) and one long-lived (s). The higher energy emission associated with the short lived excited state has been assigned as the MLCT based on the small stokes shift and DFT-calculations. DFT-calculations of the lowest energy triplet state along with the vibronic features of the lowest energy emission have allowed the long lived excited state to be assigned as metal based in character. MF10 15 min 4:21 ULTRAFAST HYDRATION DYNAMICS AND COUPLED WATER-PROTEIN FLUCTUATIONS IN APOMYOGLOBIN YI YANG, LUYUAN ZHANG, LIJUAN WANG, DONGPING ZHONG, Departments of Physics, Chemistry, and Biochemistry, The Ohio State University, Columbus, OH 43210. Protein hydration dynamics are of fundamental importance to its structure and function. Here, we characterize the global solvation dynamics and anisotropy dynamics around the apomyoglobin surface in different conformational states (native and molten globule) by measuring the Stokes shift and anisotropy decay of tryptophan with femtosecond-resolved fluorescence upconversion. With site-directed mutagenesis, we designed sixteen mutants with one tryptophan in each, and placed the probe at a desirable position ranging from buried in the protein core to fully solvent-exposed on the protein surface. In all protein sites studied, two distinct solvation relaxations (1-8 ps and 20-200 ps) were observed, reflecting the initial collective water relaxation and subsequent hydrogen-bond network restructuring, respectively, and both are strongly correlated with protein’s local structures and chemical properties. The hydration dynamics of the mutants in molten globule state are faster than those observed in native state, indicating that the protein becomes more flexible and less structured when its conformation is converted from fully-folded native state to partially-folded molten globule state. Complementary, fluorescence anisotropy dynamics of all mutants in native state show an increasing trend of wobbling times (40-260 ps) when the location of the probe is changed from a loop, to a lateral helix, and then, to the compact protein core. Such an increase in wobbling times is related to the local protein structural rigidity, which relates the interaction of water with side chains. The ultrafast hydration dynamics and related side-chain motion around the protein surface unravel the coupled water-protein fluctuations on the picosecond time scales and indicate that the local protein motions are slaved by hydrating water fluctuations. MF11 15 min 4:38 ULTRAFAST STUDIES OF RESONANCE ENERGY TRANSFER IN MYOGLOBIN: A-HELIX AND LOCAL CONFORMATIONAL FLUCTUATIONS JEFFREY A. STEVENS, JUSTIN J. LINK, YA-TING KAO, CHEN ZANG, LIJUN GUO, and DONGPING ZHONG, Department of Physics, The Ohio State University, Columbus, OH 43210. Myoglobin (Mb), a heme containing protein, is involved in the storage and release of ligands. We report here our studies of resonance energy transfer in Mb using an intrinsic tryptophan (Trp) and the prosthetic heme as an energy transfer pair. With site-directed mutagenesis, we placed one-at-a-time a single Trp donor into four locations on the A-helix. Utilizing the femtosecond up-conversion method, we examined a series of energy transfer dynamics in Mb. A molecular dynamics (MD) simulation was also used to infer structure and dipole orientation fluctuations for specific Trp. Both methodologies were used to characterize the local dynamic nature of Mb in solution compared to the static crystal structure. 93 MF12 15 min 4:55 SUB-PICOSECOND INTERSYSTEM CROSSING AND VIBRATIONAL COOLING IN THE TRIPLET MANIFOLD OF 1-NITRONAPHTHALENE CHRISTIAN REICHARDT, R. AARON VOGT and CARLOS E. CRESPO-HERNÁNDEZ, Center for Chemical Dynamics, Department of Chemistry, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, Ohio 44106. The electronic energy relaxation of 1-nitronaphthalene (1NN) was studied in different solvents using broadband transient absorption spectroscopy with femtosecond time resolution. UV excitation of 1NN populates an unrelaxed S ($$ *) state, which decays by conformational relaxation (primarily twisting of the NO group) with a time constant of 100 fs. The twisting of the NO group and formation of a structurally relaxed singlet state opens up a doorway for ultrafast intersystem crossing (ISC) to a high-energy receiver triplet state T (n$ *), which then undergoes internal conversion to form a vibrationally excited T ($$ *) state. Quantum chemical calculations that include solvent effects support the experimental observations. Our results show that an essentially barrierless path connects the initial S state to the receiver T state, which enables the observation of vibrational energy transfer and its dependence on the surrounding solvent. According to this kinetic model, which was first proposed by Crespo-Hernández et al. for 1-nitropyrene[1], the S ($$ ) electronic energy decays rapidly and irreversibly to dark triplet states, explaining why small nitro-polycyclic aromatic compounds are typically considered to be nonfluorescent. Reference [1] C. E. Crespo-Hernández, G. Burdzinski, R. Arce, J. Phys. Chem. A., 2008, 112,6313 94 MG. INFRARED/RAMAN MONDAY, JUNE 22, 2009 – 1:30 PM Room: 170 MATH ANNEX Chair: MICHEL HERMAN, Université Libre de Bruxelles, Brussels, Belgium MG01 15 min 1:30 WATER NETWORK-DEPENDENT CHARGE TRANSLOCATION IN THE NO (H O) CLUSTERS: AN OLD RIDDLE OF THE IONOSPHERE BRINGS A MICROSCOPIC GROTTHUSS MECHANISM DOWN TO EARTH RACHAEL RELPH, BEN ELLIOTT, MICHAEL KAMRATH, MARK A. JOHNSON, Yale University, Department of Chemistry, P.O. Box 208107, New Haven, Connecticut 06520; ANNE B. MCCOY, The Ohio State University, Department of Chemistry, 100 West 18th Avenue, Columbus, Ohio 43210; ALBERT A. VIGGIANO, Air Force Research Laboratory, Space Vehicles Directorate, Hanscom Air Force Base, Massachusetts 01731; and ELDON E. FERGUSON, National Ocean & Atmospheric Administration, Climate Monitoring & Diagnostics Laboratory, Boulder, Colorado 80305. The dominant ions in the D-region of the ionosphere are proton hydrates, H (H O) , which are formed through a complex mechanism involving clustering, and a water network-mediated reaction, NO (H O) + H O H (H O) + HNO , that proceeds to products only upon addition of the fourth water molecule. The presence of reactive and nonreactive isomers of NO (H O) has been invoked to explain the relatively slow rate of HNO formation from the trihydrate. To address this hypothesis, we have employed isomer-selective, pump-probe spectroscopy to determine the infrared signatures of species nominally present in the NO (H O) ion packet prepared in a supersonic jet ion source. Indeed two isomers are found to be present. Strong differences in the spectral patterns of the two isomers suggest that they have quite different geometries, which would be consistent with the isomer-specific reactivity model. One of the patterns yields strongly red-shifted activity in the OH stretching region around 2800 cm , which is readily explained by the expected behavior of the bridging hydrogen atoms in a chain structure. The motion of these protons is reminiscent of the von Grotthuss mechanism where sequential dissociation and reformation of OH bonds translocates a proton over large distances by passing through a series of small, pairwise exchanges. MG02 15 min 1:47 SPECTROSCOPIC INTERROGATION OF PHOTOINDUCED, SITE-TO-SITE MIGRATION OF SOLVENT MOLECULES IN WATER CLUSTER ANIONS TIMOTHY L. GUASCO, BEN M. ELLIOTT, MICHAEL Z. KAMRATH, and MARK A. JOHNSON, Sterling Chemistry Laboratory, Yale University, PO Box 208107, New Haven, CT 06520. We present results of a new trace isotope variation of our recently developed experimental approach in which we use IRIR pump-probe methods to measure the transition states and relative energies of isomers associated with the negatively charged water clusters. This modification, in which clusters of the form [(D O) H O] Ar are produced, allows us the powerful ability to monitor discrete, site-to-site migration of a lone water molecule as cluster melting and refreezing occurs. This technique works by first systematically disentangling the vibrational spectra of various isotopomers using hole-burning Ar predissociation spectroscopy in a triple-stage time-of-flight mass spectrometer and then monitoring the spectra of fragment ions that are created by photoevaporation of Ar atoms through the various vibrational levels identified in the spectroscopic step. 95 MG03 15 min 2:04 GENERATING SPECTRA FROM GROUND STATE WAVE FUNCTIONS: UNRAVELING ANHARMONIC EFFECTS IN THE OH H O AND H O VIBRATIONAL PREDISSOCIATION SPECTRA ANNE B. McCOY, Department of Chemistry, The Ohio State University, Columbus, OH 43210. An approach is described for calculating anharmonic spectra for polyatomic molecules using only the ground state probability amplitude. a The underlying theory is based on properties of harmonic oscillator wave functions and is tested for Morse Oscillators with a range of anharmonicities. More extensive tests are performed with H O , using the potential and dipole surfaces of Bowman and co-workers. b The resulting energies are compared to earlier studies that employed the same potential surface and the agreement is shown to be very good. The vibrational spectra are calculated for H O , D O and H O and its deuterated analogues. When possible, comparisons are made experimental spectra from 600 - 4500 cm . The frequencies and intensities of the fundamentals are found to be in excellent agreement and many combination bands involving one quantum of excitation in each of two modes are also well-reproduced. a A. b J. B. McCoy, E. G. Diken and Mark A. Johnson, J. Phys. Chem. A in press Am. Chem. Soc. 2004, 126, 5042 MG04 15 min 2:21 CONFIRMATION OF VIBRATION COUPLING IN THE SYMMETRIC CH STRETCH AS REVEALED BY COHERENCE-DETECTED FTMW-IR SPECTROSCOPY OF CH OD. SYLVESTRE TWAGIRAYEZU, TROCIA N. CLASP, DAVID S. PERRY, Department of Chemistry, The University of Akron, Akron OH 44325; JUSTIN L. NEILL, MATT T. MUCKLE, and BROOKS H. PATE, Department of Chemistry, University of Virginia, McCormick Rd., P.O. Box 400319, Charlottesville, VA 22904. Rotational state-selection with E-species transitions ( , , ) is employed to record the infrared spectra in the range 2750-2900 cm . The observed spectra of CH OD contain only one vibrational band origin whereas 12 interacting vibrational bands of CH OH are observed in the same interval. There are no interacting vibrational bands in the CH OD spectra because the first tier states are shifted out of resonance. This observation confirms that the dominant coupling pathway in the CH stretch of CH OH is the third order coupling of the CH stretch to a combination of the COH bend and an HCH bend, which subsequently couples to high order combination bands involving torsional excitation. MG05 10 min 2:38 COHERENCE-DETECTED FTMW-IR SPECTROSCOPY OF CH OD IN THE OD STRETCH REGION. SYLVESTRE TWAGIRAYEZU, DAVID S. PERRY, Department of Chemistry, The University of Akron, Akron OH 44325; JUSTIN L. NEILL, MATT T. MUCKLE, and BROOKS H. PATE, Department of Chemistry, University of Virginia, McCormick Rd., P.O. Box 400319, Charlottesville, VA 22904. Infrared spectra of the connected rotational levels of jet-cooled CH OD are recorded in the OD stretch region. The observed spectra in the range 2710 - 2740 cm result from E-species transitions ( , , ) of CH OD. For the available rotational levels (K = 0 , K = 1 and K = 2), the reduced torsional energies follow a pattern similar to the ground state. The torsional tunneling splitting in the OD stretch excited state is deduced to be 2.4 cm as compared to 2.6 cm in the ground state. Intermission 96 MG06 15 min 3:15 INFRARED SPECTROSCOPIC DEMONSTRATION OF COOPERATIVE STRENGTHENING OF AN INTRAMOLECULAR OH–O HYDROGEN BOND BY A WEAK CH–O COUNTERPART AMIT K SAMANTA, PRASENJIT PANDEY, BIMAN BANDYOPADHYAY AND TAPAS CHAKRABORTY , Physical Chemistry Department, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700032. Cooperativity is an important attribute of interconnected hydrogen bonds, and the classic examples are the size and shape dependent stability of small water clusters. The effect involving CH–O hydrogen bonds has been theoretically predicted and inferred also by analyzing crystallographic data. However, direct demonstration by infrared spectroscopy, in terms of spectral shifts, is scarce. We report here such effect probing the spectral shifts of various stretching fundamentals associated with an intramolecular OH–O=C linkage of the tautomer of 1,2-cyclohexanedione. Two types of interconnected CH–O bonds, intra- and intermolecular, with the above linkage are generated. In the first case, we have used 3-methyl 1,2-cyclohexane dione and spectral measurements reveal that the cooperative stabilization occurs with displaying a blueshifting of the CH stretching fundamental of the hydrogen-bonded methyl CH group. For the intermolecular case, a 1:1 complex between 1,2-cyclohexanedione and chloroform has been used, and the complexation results further red-shifting of the OH stretching fundamental and a concomitant blue-shifting of the C=O stretching fundamental. The details of the spectral effects are corroborated by predictions of electronic structure calculations. MG07 15 min 3:32 STEPS TOWARD EXPERIMENTAL DETECTION OF MOLECULAR PARITY VIOLATION: ROVIBRATIONAL ANALYSIS OF THE CF-STRETCHING MODE AND FIRST OVERTONE OF CHFBrI S. ALBERT, K.K. ALBERT, M. QUACK, PHYSICAL CHEMISTRY, ETH Z ÜRICH, CH-8093 ZÜRICH, SWITZERLAND; S. BAUERECKER, INSTITUT FÜR TECHNISCHE UND PHYSIKALISCHE CHEMIE, TU BRAUNSCHWEIG, D-38106 BRAUNSCHWEIG, GERMANY. The experimental detection of molecular parity violation a is of great interest because of its importance in the understanding of fundamental aspects of molecular dynamics and symmetries. One possible method for this is measuring the rovibrational or rotational frequency shifts in the infrared or microwave spectra of enantiomers b. A value of 50 mHz is predicted for vibrational frequency shifts in CHFBrI c , which is almost within the range of current infrared d and submm wave spectroscopic resolution. We report here IR-spectroscopic results and a first high resolution analysis of the infrared spectrum of CHFBrI. The FTIR spectrum of CHFBrI was recorded at 190 K and 295 K in the regions 600–1300 cm and 1800–2350 cm e . We were able to analyse the rovibrational spectra of CHF BrI ( = 1060.81569 cm ) and CHF BrI ( = 1060.77864 cm ) in the CF-stretching ( ) and its overtone regions with band centers = 2103.75730 cm for CHF BrI and = 2103.65974 cm for CHF BrI. We will discuss a possible application of CO laser quasi-resonant two photon transitions in the overtone region of CHFBrI. Finally, we will show submm spectra of CHFBrI recorded with the Zürich-FASSST spectrometer and discuss how submm wave spectroscopy based on FASSST f and phase-locked backward wave oscillatorsg can be used to determine line shifts on the order of mHz. a M. Quack, J. Stohner and M. Willeke, Annu. Rev. Phys. Chem. 2008, 59, 741, A. Bakasov, T.K. Ha and M. Quack, J. Chem. Phys. 1998, 109, 7263, R. Berger and M. Quack, J. Chem. Phys. 2000, 112, 3148. b M. Quack and J. Stohner, PRL 2000, 84, 3807, M. Quack and J. Stohner. J. Chem. Phys. 2003, 119, 11228. c J.K. Laerdahl, P. Schwerdtfeger and H.M. Quiney, PRL 2000, 84, 3811, R. Berger and J.L. Stuber, Mol. Phys. 2007, 105, 41. d C. Daussy, T. Marrel, A. Amy-Klein, C. Nguyen, C. Borde and C. Chardonnet, Phys. Rev. Lett. 1999, 83, 1554 e S. Albert and M. Quack, ChemPhysChem 2007, 8, 1271. f D. T. Petkie, T. M. Goyette, R. P. A. Bettens, S. P. Belov, S. Albert, P. Helminger and F. C. De Lucia, Rev. Sci. Instr. 1997, 68, 1675. g F. Lewen, R. Gendriesch, I. Pak, D.G. Paveliev, M. Hepp, R. Schieder and G. Winnewisser, Rev. Sci. Instrum. 1998, 69, 32. 97 MG08 15 min 3:49 INFRARED SPECTROSCOPIC INVESTIGATION OF MAGIC NUMBER HYDRATED METAL ION CLUSTERS JORDAN P. BECK, JAMES M. LISY, Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, IL 61801. Magic number clusters are clusters that appear with anomalously large intensity compared to their neighbors in mass spectra. Experimental and computational studies of magic number clusters have gained much attention in recent years. The prevailing hypothesis of the origin of the magic numbers is that the clusters form 3D nanoscale cages where all the waters are three or four-coordinated. In order to determine the importance of having only three or four-coordinated waters, we have performed infrared predissociation (IRPD) spectroscopic experiments in the free OH region of water. We investigated the magic number M (H O) clusters, where M=Cs, K, H O. These spectra are compared with spectra of non-magic clusters and anti-magic clusters. We found evidence of two-coordinated waters in magic number clusters. These results indicate that the formation of a nanoscale water cage is not an important factor in the origin of magic numbers. MG09 15 min 4:06 INFRARED SPECTROSCOPY OF SIZE-SELECTED PROTONATED MOLECULAR CLUSTERS: (N ) H , (CO) H , AND (O ) H , ALLEN M. RICKS, GARY E. DOUBERLY, and MICHAEL A. DUNCAN, Department of Chemistry, University of Georgia, Athens, Georgia 30602. Cold, rare gas tagged, gas phase protonated molecular dimers are produced in a pulsed electric discharge supersonic expansion cluster source. In such systems the proton is shared between the two molecules. The intermolecular proton transfer potential in these systems is generally very flat due to the identical proton affinities of the bound molecules. This leads to a very low frequency and very intense intermolecular proton stretch that is poorly modeled by the harmonic approximation. This intense mode also causes large amounts of coupling between vibrational modes and thus a complicated spectrum for such simple systems. The infrared spectra of the size-selected species are obtained via infrared photodissociation spectroscopy. The structure and spectroscopy (700-4000 cm ) of the dimers of protonated nitrogen, carbon monoxide and oxygen will be discussed as well as attempts to model the spectrum using sophisticated ab initio methods. MG10 15 min 4:23 INFRARED SPECTROSCOPY AND STRUCTURES OF METAL CARBONYL CATIONS, M(CO) (M= Nb,Ta,Mn), (n=1-11) Z. D. REED, A. M. RICKS, M. A. DUNCAN, Department of Chemistry, University of Georgia, Athens, GA 30602-2556. M(CO) complexes (M=Nb,Ta,Mn), (n=1-11) are produced in the gas phase by laser vaporization in a pulsed nozzle source and detected with a time of flight mass spectrometer. The carbonyl stretching region is studied using mass selected infrared photodissociation spectroscopy. The coordination number, geometry, and electronic structure of these complexes can be determined from the number of infrared-active bands, their positions, their relative intensities, and the fragmentation patterns. Complexes with CO ligands in excess of the coordination sphere are eliminated readily, leaving behind a core ion with its complete coordination sphere. Complexes at or below the coordination number do not fragment efficiently, and the argon-tagged analogues of the form M(CO) (Ar) , are investigated instead. The Mn(CO) and Ta(CO) complexes have a completed coordination sphere, consistent with their expected 18 electron stability. However, Nb(CO) shows evidence of two isomers, one with a completed coordination sphere at n=6, yielding a 16 electron complex, and another with a completed coordination sphere at n=7, yielding an 18 electron complex. V(CO) , not discussed here, is exclusively six coordinate. The geometries and electronic structure of the complexes are determined by comparison of the measured spectra to the spectra predicted by theoretical calculations. 98 MG11 10 min 4:40 INFRARED SPECTRA OF ACETYLENE-NITROUS OXIDE TRIMERS: THE (N O) -C H AND (N O) -C D M. DEHGHANY, MAHIN AFSHARI, J. N. OLIAEE, N. MOAZZEN-AHMADI, Department of Physics and Astronomy, University of Calgary, Calgary, AB T2N 1N4, CANADA; A.R.W. MCKELLAR, Steacie Institute for Molecular Sciences, National Research Council of Canada, Ottawa, ON K1A 0R6, CANADA. The spectra of the (N O) -C H and ((N O) -C D trimers in the region of the N O fundamental ( 2224 cm-1) are observed using a tuneable diode laser to probe a pulsed supersonic slit jet expansion. The observed bands have c- and b-type rotational structure and the trimer has C symmetry. The structure of the trimer can be thought of as a nonpolar N O dimer with a C H monomer lying above the dimer plane. Search for the other possible isomers of the trimer is currently underway. MG12 NON-PLANAR STRUCTURES OF THE HIGH-ENERGY ROTATIONAL CONFORMERS OF 2-METHYLBUTA-1,3-DIENE (ISOPRENE) AND 2,3-DIMETHYLBUTA-1,3-DIENE 10 min 4:52 Yu. N. PANCHENKO, Dept. of Chemistry, M. V. Lomonosov Moscow State University, Moscow 119992, Russian Federation; Ch. W. BOCK, Dept. of Chemistry and Biochemistry, Philadelphia University, Philadelphia, PA 19144; J. D. LARKIN, Dept. of Chemistry, Bloomsburg University of Pennsylvania, Bloomsburg, PA 17815; A. V. ABRAMENKOV, Dept. of Chemistry, M. V. Lomonosov Moscow State University, Moscow 119992, Russian Federation; and F. K ÜHNEMANN, Institute of Applied Physics, Bonn University, 53115 Bonn, Germany. Optimization of the geometrical parameters and determination of the force fields for rotamers of the title molecules were performed at the MP2(FC)/aug-cc-pVDZ//MP2(FC)/aug-cc-pVDZ computational level. The vibrational analyses of these conformers were carried out using scaled quantum-mechanical force field methodology. Recent experimental wavenumbers for these conformers and their deuteroisomers were incorporated into these analyses. The theoretical non-planar structures of the high-energy conformers of 2-methylbuta-1,3-diene (isoprene) and 2,3-dimethylbuta-1,3-diene were corroborated by good agreement between the experimental and theoretical wavenumbers of the molecules under investigation. The dihedral angles of the non-planar high-energy conformers for rotation around the =C–C= bond are as follows: % Æ for 2methylbuta-1,3-diene (isoprene) a and %Æ for 2,3-dimethylbuta-1,3-diene b. Previous studies performed at the HF/6-31G level gave %Æ and %Æ for the first and second compounds, respectively. a Yu. b Yu. N. Panchenko, Ch. W. Bock, J. D. Larkin, A. V. Abramenkov, F. Kühnemann, Struct. Chem. 19, 421 (2008). N. Panchenko, Ch. W. Bock, J. D. Larkin, A. V. Abramenkov, Struct. Chem. 19, 793 (2008). 99 MH. MICROWAVE MONDAY, JUNE 22, 2009 – 1:30 PM Room: 1000 McPHERSON LAB Chair: SONIA MELANDRI, Universita di Bologna, Bologna, Italy MH01 MICROWAVE SPECTROSCOPY OF SEVEN CONFORMERS OF 1,2-PROPANEDIOL 15 min 1:30 JUSTIN L. NEILL, MATT T. MUCKLE, and BROOKS H. PATE, Department of Chemistry, University of Virginia, McCormick Rd., P.O. Box 400319, Charlottesville, VA 22904-4319; F.J. LOVAS, D.F. PLUSQUELLIC, Optical Technology Division, NIST, Gaithersburg, MD 20899-8441; A.J. REMIJAN, National Radio Astronomy Observatory, 520 Edgemont Rd., Charlottesville, VA 22904-2475. Previously, two conformations of 1,2-propanediol have been identified by microwave spectroscopy by Caminati. a Here we report the assignment of five additional conformers, two from work on a Balle-Flygare type cavity FTMW spectrometer at NIST, operating between 8 and 26 GHz, and three from a deep average scan on the chirped pulse Fourier transform microwave (CP-FTMW) spectrometer at the University of Virginia, operating between 6.5 and 18.5 GHz. All seven of the assigned conformers contain an intramolecular hydrogen bond between the two hydroxyl groups. Stark effect measurements have been performed on the cavity FTMW spectrometer to determine the dipole moments of the three lowest energy conformers. Relative abundances of the conformers have also been determined from the CP-FTMW spectrum. A subsequent interstellar search toward Sgr B2(N) yielded negative results with an upper limit to the total column density that is less than those of glycolaldehyde and ethylene glycol. a W.Caminati, J. Mol. Spectrosc. 86 (1981) 193-201. MH02 MOLECULES WITH A SIX-FOLD BARRIER: MICROWAVE SPECTRUM OF TOLUENE 15 min 1:47 VADIM V. ILYUSHIN, Institute of Radio Astronomy of NASU, Chervonopraporna 4, 61002 Kharkov, Ukraine; ZBIGNIEW KISIEL, LECH PSZCZ ÓLKOWSKI, Institute of Physics, Polish Academy of Sciences, Al. Lotników 32/46, 02-668 Warszawa, Poland; HEINRICH M ÄDER, Institut für Physikalische Chemie, Christian-Albrechts Universität zu Kiel, Olshausenstrasse 40, D-24098, Kiel, Germany; JON T. HOUGEN, Optical Technology Division, National Institute of Standards and Technology, Gaithersburg, MD 20899-8441. Recent progress in analysis and fitting of transitions in the toluene microwave spectrum characterized by & 30, ' 12, and the free rotor quantum number 3 will be presented. The analysis was carried out using a new program which is specifically designed for six-fold barrier molecules, and allows the user to select almost any symmetry-allowed torsionrotation term for inclusion in the fitting Hamiltonian. The program is based on the theoretical framework developed by Sørensen and Pedersen a in their application of the Longuet-Higgins permutation-inversion group G to the microwave spectrum of CH NO . In the analysis we have used the published and rather extensive unpublished data from previous studies as well as recent new measurements of the toluene microwave spectrum in the 8 – 18 GHz range. A rather successful fit of over 350 toluene microwave transitions in the abovementioned quantum number range has been achieved. The fit is close to the estimated experimental accuracy and includes more than thirty intertorsional = +3 = -3 transitions. a G. O. Sørensen, T. Pedersen, Studies in Physical and Theoretical Chemistry, Elsevier, 23, 219–236 (1983). 100 MH03 15 min 2:04 INTERACTION OF THE HYPERFINE COUPLING AND THE INTERNAL ROTATION IN METHYL FORMATE a M. TUDORIE, D. JEGOUSO, G. SEDES, T. R. HUET, Laboratoire de Physique des Lasers, Atomes et Molécules (PhLAM) UMR 8523 CNRS, B ât. P5, Université des Sciences et Technologies de Lille 1, 59655 Villeneuve d’Ascq Cedex, France; and L. H. COUDERT, LISA, CNRS/Universit és Paris 12 et 7, 61 Avenue du Général de Gaulle, 94010 Créteil, France. Experimental and theoretical analysis of the hyperfine structure of the non-rigid methyl formate (HCOOCH ) molecule will be reported. 25 -type rotation-torsion lines (nondegenerate levels) and 24 -type rotation-torsion lines (doubly degenerate levels) were recorded in the 2–20 GHz range using the new Lille FTMW spectrometer, characterized by an instrumental resolution of 0.46 kHz. The high resolution of this spectrometer, limited by the Doppler widths, allowed us to resolve most hyperfine patterns. As in this molecule, the hyperfine coupling is due to four hydrogen atoms ( ), magnetic spin-spin and spin-rotation couplings b take place. A theoretical calculation of the hyperfine energy levels was carried out, taking into account these two couplings, and using an effective hyperfine Hamiltonian accounting for the averaging effects due to the large amplitude internal rotation. c In the paper, comparisons between observed and calculated hyperfine patterns will be presented. As the present measurements indicate that hyperfine patterns arising for -type rotation-torsion lines are systematically wider than those arising for -type rotation-torsion lines, we hope to confirm this result theoretically. a This work is supported by the ANR-08-BLAN-0054 contract Krisher, and Loubser, J. Chem. Phys. 40 (1964) 257 c Coudert and Lopez, J. Mol. Spectrosc. 239 (2006) 135 b Thaddeus, MH04 15 min 2:21 ASSIGNMENT OF THE SUB-MILLIMETER WAVE SPECTRUM OF METHYL CARBAMATE, NH COOCH , IN THE FIRST EXCITED STATE OF THE METHYL GROUP INTERNAL ROTATION P. GRONER, Department of Chemistry, University of Missouri-Kansas City, Kansas City, MO 64110-2499. The rotational spectrum of methyl carbamate in the first excited torsional state (up to 149 GHz) has been analyzed recently for rotational quantum number & up to 20 together with transitions in the ground state a . An extended analysis of the rotational spectrum in the ground state between 10 and 371 GHz with over 6000 transitions with & up to 60 has also been published b . In the spectra recorded at that time by the FASSST method, about 3000 transitions belonging to the first torsional excited state of the methyl group have now been assigned and analyzed, about half of them belonging to the torsional species. Both the newly assigned and previously published transitions have been used to fit less than 45 spectroscopic parameters of an effective rotational Hamiltonian for such systems c , achieving a dimensionless standard deviation of 1.33. A somewhat unexpected result was the value of the ( parameter of 0.063628(20) which differed significantly from the value obtained for the ground state of 0.058791(15). The discrepancy will be investigated in the near future. Hopefully, a resolution of the problem can be achieved by a combined fit of all excited and ground state transitions using common ( and ) parameters with ) as the angle between the (-axis and the principal axis. a V. Ilyushin, E. Alekseev, J. Demaison, I. Kleiner, J. Mol. Spectrosc. 240, 127 (2006). Groner, M. Winnewisser, I. R. Medvedev, F. C. De Lucia, E. Herbst, K. V. L. N. Sastry, Astrophys. J. Suppl. Ser. 169, 28 (2007). c P. Groner, J. Chem. Phys. 107, 4483 (1997). b P. 101 MH05 15 min 2:38 FORBIDDEN TRANSITIONS IN THE VERY RICH PURE ROTATIONAL SPECTRUM OF TRANS-1IODOPERFLUOROPROPANE CHRISTOPHER T. DEWBERRY, GARRY S. GRUBBS II, and STEPHEN A. COOKE, The Department of Chemistry, University of North Texas, P.O. Box 305070, Denton, TX, 76203-5070. Using both chirped pulse-, and low frequency cavity-based Fourier transform spectroscopy over 700 transitions have been recorded for the title molecule for the first time. The C , C and C carbon-13 species have been observed in natural abundance allowing a substitution structure for the CCC backbone to be determined. Nearly all the transitions observed were either -type branches or *-type + branches. No -type transitions were observed. The , , , , , and , components of the iodine nuclear quadrupole coupling tensor have been determined. Of note, several forbidden transitions were also observed, such as & ½ ·½ - = 14 23/2 12 21/2. In this particular case it seems that the upper energy level is nearly degenerate with a level connected to the lower energy level by a dipole component term, but the lower energy level is also nearly degenerate with a second level connected to the upper energy level, again by a dipole component term. The two intermediate energy levels are themselves connected by a dipole component term. Near degeneracies such as these, together with a large , value ( 1 GHz) mean that certain & transitions become allowed. This phenomena has been previously observed for 1-iodopropane by Fujitake and Hayashi (J. Mol. Spect, 127, (1988), 112-124). MH06 SOME EFFECTS OF SUCCESSIVE FLUORINATION ON 1-IODOPROPANE 15 min 2:55 GARRY S. GRUBBS II, CHRISTOPHER T. DEWBERRY, and STEPHEN A. COOKE, The Department of Chemistry, University of North Texas, P.O. Box 305070, Denton, TX, 76203-5070. Fourier transform radiofrequency and microwave spectroscopies have been used to record the pure rotational spectra of 1iodo-3,3,3-trifluoropropane (I3FP) and 1-iodo-2,2,3,3,3-pentafluoropropane (I5FP). In both cases the compound of interest was seeded in a supersonic expansion of argon gas issued from a pulsed solenoid valve. Several hundred transitions have been recorded for both species. Using the same instrumentation we have also remeasured several rotational transitions for 1iodopropane for which ./#0 and conformers are visible; previous workers have shown that the ./#0 conformer of 1-iodopropane is the most stable. The substitution of three fluorines for the hydrogens on C of 1-iodopropane has the effect of locking the CCCI dihedral angle into the conformer for the fluorinated species in our experiments. Further observations have shown that the largest component of the dipole moment lies along the -axis for -1-iodopropane, but lies along the *-axis for -I5FP, switching back along the -axis for -I3FP (but presumeably in the opposite direction than in 1-iodopropane). Spectroscopic constants will be presented and discussed. MH07 ROTATIONAL SPECTRA OF HALOGENATED ETHERS USED AS VOLATILE ANAESTHETICS 15 min 3:12 ALICIA VEGA-TORIBIO and ALBERTO LESARRI, Departamento de Quı́mica Fı́sica y Quı́mica Inorgánica, Facultad de Ciencias, Universidad de Valladolid, E-47011 Valladolid, Spain; RICHARD D. SUENRAM, Department of Chemistry, University of Virginia, Charlottesville, VA 22904, USA; JENSUWE GRABOW, Institut für Physikalische Chemie und Elektrochemie, Leibniz Universit ät Hannover, Callinstraße 3 - 3A, D-30167 Hannover, Germany. Following previous microwave investigations by Suenram et al. a we will report on the rotational spectrum of several halogenated ethers used as volatile anaesthetics, including sevoflurane ((CF ) CH-O-CH F), isoflurane (CF CHCl-OCHF ), enflurane (CHFClCF -O-CHF ) and methoxyflurane (CHCl CF -O-CH ). This study has been conducted in the 6-18 GHz centimetre-wave region using Balle-Flygare-type FT-microwave spectroscopy. The results will include the analysis of the rotational spectra of minor species in natural abundance ( C and O in some cases), structural calculations and auxiliary ab initio modelling. The conformational and structural conclusions will be compared with previous gas-phase electron diffraction and solid-state X-ray diffraction analysis. a R. D. Suenram, D. J. Brugh, F. J. Lovas and C. Chu, 51 OSU Int. Symp. On Mol. Spectrosc., Columbus, OH, 1999, RB07 102 MH08 15 min 3:29 ISOTOPOLOGUE-SENSITIVE DETECTION USING CHIRPED-PULSE FT-MW SPECTROSCOPY: MINOR SPECIES OF PROPOFOL ALBERTO LESARRI, Departamento de Quı́mica Fı́sica y Quı́mica Inorgánica, Facultad de Ciencias, Universidad de Valladolid, E-47011 Valladolid, Spain; JUSTIN NEILL, MATT MUCKLE, STEVEN T. SHIPMAN, BROOKS H. PATE and RICHARD D. SUENRAM, Department of Chemistry, University of Virginia, Charlottesville, VA 22904, USA; WALTHER CAMINATI, Dipartimento di Chimica ”G. Ciamician”, Università di Bologna, I-40126 Bologna, Italy. The capabilities of chirped-pulse FT-microwave spectroscopy to achieve full-bandwidth (11 GHz) isotopologue-sensitive detection have been tested on the 13-heavy atoms molecule of propofol (2,6-diisopropylphenol). The analysis of the rotational spectrum using moderate signal averaging (10 k FIDs) had previously detected the presence of two conformers arising from the combined internal rotations of the hydroxyl and the two isopropyl groups a. In the new experiment reported here 600 k FIDs were coherently averaged, using three pulsed nozzle sources and reading multiple FIDs per sample injection cycle to reduce the total acquisition time and sample consumption. The new spectrum revealed a very large number of weak transitions, suggesting that full-band C sensitivity had been surpassed. The new data have resulted in the assignment of a third conformer of propofol, followed by all twelve C-monosubstituted species in natural abundance for the most stable conformer. The isotopic information confirmed the molecular structure for the preferred conformation of propofol, validating the ab initio predictions for this compound. The potential function for the OH internal rotation has been determined using a flexible model. a A. Lesarri, S. T. Shipman, G. G. Brown, L. Alvarez-Valtierra, R. D. Suenram and B. H. Pate, 63 OSU Int. Symp. On Mol. Spectrosc., Columbus, OH, 2008, RH07 Intermission MH09 15 min 4:00 HIGH RESOLUTION INVESTIGATION OF SILACYCLOBUTANE USING FTMW AND SYNCHROTRON BASED FTIR SPECTROSCOPY CODY VAN DIJK, SAMANTHA VAN NEST, ZIQIU CHEN and JENNIFER VAN WIJNGAARDEN, Department of Chemistry, University of Manitoba, Winnipeg MB R3T 2N2 Canada. The rotational spectrum of silacyclobutane (c-C H Si) has been measured between 8 and 24 GHz using Fourier transform microwave spectroscopy. Although the microwave spectrum was previously reported a, the current study is the first observation of tunneling splitting in the ground state due to ring puckering. The observed transitions within each tunneling state obey a-type selection rules and c-type transitions that connect the inversion states have also been observed. The rotational constants determined were used to model the rotational structure of several vibrational bands of silacyclobutane including the weak ring puckering mode at 157 cm . The far infared spectrum of silacyclobutane was recorded using the far infrared beamline at the Canadian Light Source and includes multiple tunneling doubled bands. The ongoing analysis of the incredibly rich vibrational spectrum of silacyclobutane will be discussed. a W. C. Pringle J. Chem. Phys. 54 (4979), 1971. 103 MH10 ROTATIONAL SPECTRA OF THE ANTI-ANTI CONFORMER OF N-BUTYLGERMANE 10 min 4:17 SEAN A. PEEBLES, REBECCA A. PEEBLES, AMANDA L. STEBER, and DANIEL A. OBENCHAIN, Department of Chemistry, Eastern Illinois University, 600 Lincoln Avenue, Charleston, IL 61920; GAMIL A. GUIRGIS, Department of Chemistry and Biochemistry, The College of Charleston, 66 George Street, Charleston, SC 29424; HOWARD D. STIDHAM, Department of Chemistry, University of Massachusetts, 710 North Pleasant Street, Amherst, MA 01003. Rotational spectra for the five naturally occurring germanium isotopologues of the anti-anti conformer of -butylgermane have been measured using a Fourier-transform microwave spectrometer operating in the 4-18 GHz range. This conformer, determined by ab initio calculations at the MP2/6-311++G(2d,2p) level to be the most stable of five possible conformers, has a heavy atom planar structure and dipole moment values (for the Ge species) of % D and % D, with % D. Nuclear quadrupole coupling constants have also been determined for the Ge nucleus and are in reasonable agreement with ab initio calculations. Small splittings, which were particularly apparent on the very weak *-type transitions for all isotopic species, are presumably due to rotation of one or both of the internal rotors (CH and GeH ) although these splittings have not yet been resolved sufficiently well to allow determination of any internal rotation parameters. The spectroscopic data will be discussed in relation to ab initio results and compared with results for similar species. MH11 15 min 4:29 ROTATIONAL SPECTROSCOPY OF TWO TELLUROL COMPOUNDS : ETHYL AND VINYL-TELLUROL R. MOTIYENKO, L. MARGULÈS, M. GOUBET, Laboratoire PhLAM, CNRS UMR 8523, Universit é de Lille 1, 59655 Villeneuve d’Ascq Cedex, France; H. MØLLENDAL, Centre for Theoretical and Computational Chemistry (CTCC), University of Oslo, P.O. Box 1033, Blindern, NO-0315 Oslo, Norway; and J. C. GUILLEMIN, Sciences Chimiques de Rennes-Ecole Nationale Sup érieure de Chimie de RennesCNRS, 35700 Rennes, France. Among the compounds containing a chalcogen, the tellurols (R-TeH) have been poorly investigated previously. Only H Te was studied in rotational spectroscopy a. This fact can be explained by high toxicity and high chemical reactivity of these compounds. However quite recently, a new method allowing easily obtention of pure samples has been reported b. Thanks to this approach, very high acidity of these tellurols in gas phase has been measured c and photoelectron spectra have been recorded d. It should be noted that, even if simple derivatives are known since a long time e , no microwave spectrum of these compounds has been recorded previously. The determination of their rotational constants is however a determining step to have a quite complete knowledge of such systems and to be able to perform comparisons of their physicochemical properties with those of the corresponding thiols and selenols which have been more extensively studied. The rotational spectra of vinyl and ethyl-tellurol have been recorded in the frequency range up to 210 GHz. For both compounds gauche forms have been assigned due to rather distinguishable patterns of a-type transitions. The assignments were confirmed by comparison with the results of ab initio calculations. For ethyl-tellurol the rotational transitions were observed as doublets. The splittings are probably caused by tunneling effect between two equivalent configurations (gauche , gauche). The assignment and analysis of the rotational spectra of both molecules is in progress. The latest results will be reported. a I. N. Kozin, P. Jensen, O. Polanz, S. Klee, L. Poteau, and J. Demaison, J. Mol. Spectrosc., 180 402-413 (1996) C. Guillemin, A. Bouayard, D. Vijaykumar, D. Chem. Commun., 1163-1164 (2000) c J. C. Guillemin, El. H. Riague, J. F. Gal, P. C. Marris, O. Mo., M. Yanez, Chem. Eur. J. 11, 2145-2153 (2005) d B. Khater, J. C. Guillemin, G. Bajor, T. Veszprémi, P. C. Marris, O. Mo., M. Yanez, Inorg. Chem. 112, 3053-3060 (2008) e A. Baroni, Atti Accad. Naz. Lincei, Cl. Sci. Fis., Mat. Nat., Rend. 27, 238242 (1938) b J. 104 MH12 ROTATIONAL SPECTRA OF ADRENALINE AND NORADRENALINE 15 min 4:46 V. CORTIJO, J. C. LÓPEZ, and J. L. ALONSO, Grupo de Espectroscopı́a Molecular (GEM), Departamento de Quı́mica Fı́sica y Quı́mica Inorgánica, Facultad de Ciencias, Universidad de Valladolid, E-47005 Valladolid, Spain. The emergence of Laser Ablation Molecular Beam Fourier Transform Microwave (LA-MB-FTMW) spectroscopy has rendered accessible the gas-phase study of solid biomolecules with high melting points. Among the biomolecules to benefit from this technique, neurotransmitters have received special attention due to the lack of experimental information and their biological relevance. As a continuation of the work on norephedrine, ephedrine and pseudoephedrine a we present the study of adrenaline and noradrenaline. The comparison between the experimental rotational and N nuclear quadrupole coupling constants and those calculated ab initio provide a definitive test for molecular structures and confirm unambiguously the identification of four conformers of adrenaline and three conformers of noradrenaline. Their relative population in the jet has been evaluated by relative intensity measurements of selected rotational transitions. The most abundant conformer in both neurotransmitters present an extended AG configuration with a OH N hydrogen bond in the side chain. a J.L. Alonso, M.E. Sanz, J.C. López and V. Cortijo, J. Am. Chem. Soc. (in press), 2009 MH13 10 min 5:03 MEASUREMENT OF NITROGEN HYPERFINE STRUCTURE ON THE 53 CM (562 MHz) BUTYRONITRILE LINE CHRISTOPHER T. DEWBERRY, GARRY S. GRUBBS II, ANDREW RAPHELTa and STEPHEN A. COOKE, The Department of Chemistry, University of North Texas, P.O. Box 305070, Denton, TX, 762035070. Recent improvements to our cavity-based Fourier transform radiofrequency spectrometer will be presented. Amongst other improvements use of Miteq amp, model AMF-6F-00100400-10-10P (0.1 GHz to 4 GHz, 65 dB gain minimum, 1 dB noise figure maximum) together with shielding from an improved Faraday cage have significantly helped us in this regard. Electromagnetic fields within our near-spherical cavity have been modeled and results will be presented. We have been able to easily resolve the nitrogen hyperfine structure on the + transition 1 located at 562 MHz. This result will be discussed. a NSF-REU student from Concordia University, Nebraska 105 MH14 MICROWAVE SPECTROSCOPY OF 2-FURANCARBOXYLIC ACID 15 min 5:15 R. MOTIYENKOa , M. GOUBET, L. MARGULÈS, G. WLODARCZAK, Laboratoire PhLAM, CNRS UMR 8523, Université de Lille 1, 59655 Villeneuve d’Ascq Cedex, France; E. A. ALEKSEEV, S. F. DYUBKO, Institute of Radio Astronomy of NASU, Chervonopraporna 4, 61002 Kharkov, Ukraine. The structure and harmonic force field of 2-furancarboxylic acid have been optimized at MP2/aug-cc-pVTZ level of theory. Geometries of four different conformations have been calculated: Cc, Ct, Tc, Tt. Two of them: Cc and Tc were unambiguously found the most stable conformations and very close in energy. Since two other conformers were found to be too high in energy (E=9 kJ/mol and 23.5 kJ/mol correspondingly for Tt and Ct) only Cc and Tc conformations were considered in interpretation of the spectroscopic observations. The rotational spectra have been recorded in the frequency range 5 – 20 GHz using MB-MWFT spectrometer in Lille and in the frequency range 50 – 240 GHz using conventional absorption spectrometers in Kharkov and Lille. Rotational transitions of both Cc and Tc conformation have been assigned and rotational parameters have been obtained. It is interesting to note that for both conformations the values of sextic centrifugal distortion parameters were found to be too small and the rotational transitions with quantum number J as high as 80 and K as high as 50 can be fitted within experimental accuracy (0.010 – 0.020 MHz) using only quartic centrifugal distortion terms. Besides ground states several excited vibrational states have been assigned in conventional absorption spectra. Most of the excited states assigned were found to be coupled by Coriolis-type interaction. The results of microwave studies and ab initio calculations will be discussed. a The support of INTAS YSF (INTAS Ref. Nr 06-1000014-5984) is gratefully acknowledged MH15 15 min 5:32 ROTATIONAL SPECTRA OF -, -, AND -CYANOPHENOL AND INTERNAL ROTATION OF -CYANOPHENOL ANDREW R. CONRAD, NATHAN Z. BAREFOOT, and MICHAEL J. TUBERGEN, Department of Chemistry, Kent State University, Kent, Ohio 44242. Rotational spectra of p-, m-, and o-cyanophenol have been measured in the range of 10.5 - 21 GHz and fit using Watson’s A-reduction Hamiltonian coupled with nuclear quadrupole coupling interaction terms for the N nuclei. Ab initio calculations at the MP2/6-311++G** level predict the cis conformers of m- and o-cyanophenol to be more stable due to the intramolecular hydrogen bonding interaction between the hydroxyl hydrogen and the cyano nitrogen. We recorded 14 and *-type rotational transitions for cis m-cyanophenol and 16 - and *-type rotational transitions for trans m-cyanophenol. The rotational constants are % MHz, % MHz, and % MHz and % MHz, % MHz, and % MHz for the cis and trans species respectivly. We recorded 25 - and *-type rotational transitions for cis o-cyanophenol; the rotational constants are % MHz, % MHz, and % MHz. The trans conformer of o-cyanophenol was not observed. Rotational transitions of the p-cyanophenol monomer are split due to the symmetric internal rotation of the hydroxyl group with respect to the aromatic ring. We recorded 25 - and *-type rotational transitions for p-cyanophenol; the *type transitions are split by 40 MHz. The rotational constants are % MHz, % MHz, and % MHz and the ground state spitting is 20.1608(6) MHz. 106 MI. ELECTRONIC MONDAY, JUNE 22, 2009 – 1:30 PM Room: 1015 McPHERSON LAB Chair: SANG KUK LEE, Pusan National University, Pusan, Korea MI01 15 min 1:30 APPLICATION OF THE ’MLR’ DIRECT POTENTIAL FITTING (DPF) METHOD FOR THE STATE OF Cs JOHN A. COXON, Department of Chemistry, Dalhousie University, Halifax, Nova Scotia B3H 4J3, Canada; PHOTOS G. HAJIGEORGIOU, Department of Life and Health Sciences, University of Nicosia, 46 Makedonitissas Avenue, P.O Box 24005, 1700 Nicosia, Cyprus. a A set of 16544 - fluorescence line positions with a measurement precision of 0.001 cm , and which samples ground state levels up to = 135 lying about 28 cm below the dissociation limit, has been employed in least-squares fits using the MLR direct potential fitting approach b . As well as the extended MLR model employed recently for Li , a further extension employing three y -variables leads to an optimum model for Cs that ensures a realistic extrapolation into the long-range region in accord with the theoretical dispersion constants. a C. b R. Amiot and O. Dulieu, J. Chem. Phys. 117, 5155 (2002). J. Le Roy and R. D. E. Henderson, Mol. Phys. 105, 663 (2007). MI02 15 min 1:47 AN EXTENSION OF THE ‘MLR’ POTENTIAL FUNCTION FORM WHICH ALLOWS FOR AN ACCURATE DPF TREATMENT OF Li , WHICH COUPLES TO TWO OTHER STATES NEAR THEIR ASYMPTOTES NIKESH S. DATTANI and ROBERT J. LE ROY, Department of Chemistry, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada; AMANDA J. ROSS, Universit é de Lyon F-69622, Lyon, France; Universit é Lyon 1, Villeurbanne; CNRS, UMR5579, LASIM; COLAN LINTON, Physics Department, University of New Brunswick, Fredericton, New Brunswick E3B 5A3, Canada. The only potential energy functions for the state of Li published to date were conventional RKR curves based on experimental data for the vibrational levels 1 , a and they do not yield realistic predictions for the very weakly bound levels 1 for Li and 1 for Li , which were subsequently observed using photoassociation spectroscopy (PAS). b A recent analysis of data for the and systems of Li was unable to incorporate these PAS data, and this was due to the lack of a potential function form with the ability to accurately describe the behaviour of the potential for a molecule which becomes coupled to two other distinct states near the dissociation asymptote.c The current work presents and tests an extension of the ‘Morse/Long-Range’ (MLR) potential function form d which does provide an accurate description of the – state potential at all internuclear distances, including the longrange region where the three-state coupling occurs. The extension is based on expressions reported by Aubert-Frécon and co-workers, e which show that the long-range tail of this potential is one of the eigenvalues of a 3x3 Hamiltonian matrix. Accordingly, this extension requires the diagonalization of this matrix at each internuclear distance . Although this can be done analytically, we show that the diagonalization is in fact computed more efficiently numerically, and leads to a more accurate potential energy function. a F. Martin et al., Spectrochimica Acta 44A, 1369 (1988); C. Linton et al., J. Chem. Phys. 91, 6036 (1989). W.I. McAlexander et al., Phys. Rev. A 51, R871 (1995); E.R.I. Abraham et al. J. Chem. Phys. 103, 7773 (1995). c N.S. Dattani, et al., 63 Ohio State University Int. Symp. on Molec. Spec. (2008), paper RC11. d R.J. Le Roy and R.D.E. Henderson, Mol. Phys. 105, 663 (2007); R.J. Le Roy et al., J. Chem. Phys. (2009, submitted). e Martin et al., Phys, Rev. A 55, 3458 (1997); M. Aubert-Frécon et al., J. Mol. Spectrosc. 192, 239 (1998). b 107 MI03 15 min 2:04 THEORETICAL AND SPECTROSCOPIC INVESTIGATIONS OF ALKALI METAL-RARE GAS INTERACTION POTENTIALS JIANDE HAN, JEREMY M. MERRITT and MICHAEL C. HEAVEN, Department of Chemistry, Emory University, Atlanta, GA 30322. Alkali vapor lasers pumped by diode lasers are currently being investigated in several laboratories. One problem with this type of device is the poor matching of the relatively broad linewidth of the pump source with the very narrow absorption lines of the atom. Previously, pressure broadening has been used to increase the fraction of the pump laser radiation absorbed. It is also possible that the formation and excitation of alkali metal-rare gas dimers (M-Rg) could be used to achieve the desired spectral broadening. The interactions between M( S)+Rg pairs are weak, and the potential energy curves exhibit shallow minima that are characteristic of van der Waals bonds. The M( P)+Rg interactions are much stronger, having characteristics that suggest the formation of incipient chemical bonds. Excitation of the continuum regions of the M( P)RgM( S)Rg transitions offers attractive possibilities for utilization of broad band pump radiation in an alkali vapor laser. To explore this possibility we are mapping out the M-Rg potential energy curves using ab initio theoretical methods, in parallel with laser excitation and dispersed fluorescence spectroscopy. MI04 15 min 2:21 ONE- AND TWO-PHOTON SPECTROSCOPY OF ALKALI ATOMS ON HELIUM NANODROPLETS AT 3 eV ENERGY ALEXANDRA PIFRADER, OLIVIER ALLARD, GERALD AUBÖCK, CARLO CALLEGARI, and WOLFGANG E. ERNST, Institute of Experimental Physics, TU Graz, Petersgasse 16, 8010 Graz, Austria/EU; FRANCESCO ANCILOTTO, INFM - Dipartimento di Fisica, Universit à di Padova, Via Marzolo 8, I-35131 Padova Italy. We use the fundamental and second-harmonic of a ns-pulsed : laser with a 5 kHz repetition rate to measure the laser-induced fluorescence spectra of Rb atoms on the surface of superfluid helium nanodroplets. Because of the shift and broadening induced by the droplet (the first in particular becoming increasingly large for these high-energy levels) assignment based on proximity to known gas-phase transitions is no longer reliable. The and levels in particular, both accessible by a two-photon transition, are sufficiently close in energy that even a description in terms of pure atomic states may be questionable. We obtain supplementary information from gated-photon counting measurements of the emitted fluorescence. Because atoms dissociate from the droplet upon excitation, emission occurs from the gas phase, so we use the known gas-phase lifetimes of all levels involved to interpret our data. We assign one band observed with the second-harmonic beam to the spectrum of the " one-photon transition at . A second band observed with the fundamental beam at cm is assigned to the cm two-photon transitions based on the measured lifetime of the cascading fluorescence. We further support the assignment with model calculations of the Rb-droplet interaction potential, taking the mixing of atomic states into account. 108 MI05 15 min 2:38 ROTATIONALLY RESOLVED SPECTROSCOPY OF THE ELECTRONICALLY EXCITED C AND D STATES OF XeKr AND XeAr LORENA PITICCO, MARTIN SCHÄFER, and FRÉDÉRIC MERKT, ETH Zürich, Laboratorium f ür Physikalische Chemie, Wolfgang-Pauli-Strasse 10, 8093 Z ürich, Switzerland. Informations on excited electronic states of the heteronuclear rare-gas dimers XeRg (Rg=Kr, Ar) available in the literature are limited to the vibrational structure of several band systems in the VUV range of the electromagnetic spectrum. a Using a near-Fourier-transform-limited vacuum-ultraviolet laser system b spectra of the C X and D X band systems of several isotopomers of XeKr and XeAr were recorded at high resolution in the wavenumber range from 77 000 cm to 77 350 cm by resonance-enhanced two-photon ionization spectroscopy. The rotational and vibrational structures of the C X and D X band systems could be fully resolved and assigned on the basis of isotopic shifts, combination differences and the ground state microwave spectra c . The orbital hyperfine structure of the C1 state could be resolved for the Xe Ar and Xe Ar isotopomers. Potential energy functions and a full set of spectroscopic parameters were derived for the ground and excited states. a D. M. Mao, X. K. Hu, S. S. Dimov, R. H. Lipson, J. Phys. B 29, L89 (1996). O. Zehnder, F. Merkt, Mol. Phys. 106, 1215 (2008). O. Zehnder, F. Merkt, J. Chem. Phys. 128, 014306 (2008). b U. Hollenstein, H. Palm and F. Merkt, Rev. Sci. Instr. 71, 4023 (2000). c W. Jäger, Y. Xu, M. C. L. Gerry, J. Chem. Phys. 99, 919 (1993). MI06 TWO-PHOTON RESEONANT SECOND HARMONIC GENERATION IN ATOMIC XEON 15 min 2:55 Y. J. SHI, W. AL-BASHEER, Department of Chemistry, University of Calgary, Calgary, Alberta, T2N 1N4; R. I. THOMPSON, Department of Physics and Astronomy, University of Calgary, Calgary, Alberta, T2N 1N4. Vacuum ultraviolet (VUV) radiation at 124.8 nm (9.93 eV) was produced from two-photon resonant second harmonic generation (SHG) in a Xeon gaseous medium and used to probe molecular samples of acetone, furan, thiophene, ammonia, and methane. The mass spectra recorded from the species with ionization energies below 9.93 eV were dominated by the parent ions. The parent ions were only observed when the incident UV radiation was tuned to resonate with the two-photon transition 5p ( P )6p[1/2] - 5p S of Xe at 80119.474 cm . The pressure dependence and the resonant nature of the parent ions observed support the mechanism for SHG as the ionization-initiated electric field induced SHG via the thirdorder nonlinear susceptibility, , , which is enhanced by the coupling between the 5p ( P )6p[1/2] and the nearby 5p ( P )5d[1/2] states of Xe atoms. Intermission 109 MI07 15 min 3:30 A NEW ONE-ELECTRON EFFECTIVE POTENTIAL FOR CaF BASED ON AB-INITIO CALCULATIONS STEPHEN L. COY, Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139; BRYAN M. WONG, Sandia National Laboratory, Livermore, CA 94551-0969; and ROBERT W. FIELD, Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139. The Rydberg spectrum of CaF has been extensively analyzed both theoretically and experimentally, and new QDT fit and Stark/polarization results will soon be reported. In these results, a new level of detail is achieved that enables a comparison between experimental results and reaction matrix calculations for state decompositions, and dependences on R(Ca-F), as well as energies. The most commonly used potential for the Rydberg states of CaF was presented a decade ago a . It has been effective in predicting energies for electronic states with R(Ca-F) near the equilibrium separation, but does not include any variation with internuclear separation, and predicts quantities such as the ion-core dipole moment that disagree with ab-initio results as a function of R. We have performed all-electron ccsd(T) calculations for - and test-charge potential calculations for a wide range of R(Ca-F) values and test-charge angular positions. We will discuss the differences between these new results and the earlier potential and describe a new one-electron effective potential for CaF. a M. Arif, Ch. Jungen and A. L. Roche J. Chem. Phys. 106(10), 4102 (1997). MI08 15 min 3:47 ADAPTIVE ANALYTIC MAPPING PROCEDURES FOR SIMPLE AND ACCURATE CALCULATION OF SCATTERING LENGTHS AND PHOTOASSOCIATION ABSORPTION INTENSITIES ROBERT J. LE ROY, Guelph-Waterloo Centre for Graduate Work in Chemistry and Biochemistry, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada; VLADIMIR V. MESHKOV and ANDREJ V. STOLYAROV, Department of Chemistry, Moscow State University, GSP-2 Leninskie Gory 1/3, Moscow 119991, Russia. We have shown that one and two-parameter analytical mapping functions such as 2 ! " " #$%$2 and 2 ! " " transform the conventional radial Schrödinger equation into equivalent alternate forms 32 . 2 & 2 ' 32 $%( . 2 & 2' 32 2 respectively, in which . 2 2 2 . a Such transformed equations are defined on the finite domain 2 & ', and 32 2 $ they may be solved routinely using standard numerical methods at all energies up to and including the potential asymptote. At the energy of the potential asymptote, the -wave scattering length can be expressed in terms of the logarithmic derivative of the wave function 32 at the right-hand boundary point: 32 32 $%( " $ 32 2 32 2 The required logarithmic derivative of 32 can be obtained efficiently by direct outward integration of the differential equation all the way to the end point 2 , which corresponds to the limit . This zero-energy wavefunction may " also be combined with wavefunctions for ordinary bound states generated in the same manner to calculate photoassociation absorption matrix elements using any appropriately modified Franck-Condon computer program. VVM is grateful to INTAS grant 06-1000014-5964 for support. a V.V. Meshkov, A.V. Stolyarov, and R.J. Le Roy, Phys. Rev. A 78, 052510 (2008). 110 MI09 15 min 4:04 DETERMINATION OF THE Be (X) POTENTIAL ENERGY CURVE USING STIMULATED EMISSION PUMPING SPECTROSCOPY J. M. MERRITT, V. E. BONDYBEY, and M. C. HEAVEN, Department of Chemistry, Emory University, Atlanta, GA 30322. Calculations for the ground state of Be are very sensitive to the level of theory used and the basis sets. Because of this sensitivity, calculations on Be have been used as a test for geminal approaches, coupled cluster methods at various levels of approximation, many-body methods, density functional theory, Monte-Carlo, multi-reference CI and full CI methods. These studies have yielded a wide range of values for the well depth and spectroscopic constants. There has been only one previously reported experimental study of the Be (X) binding energy. Bondybey (Chem. Phys. Lett. 109, 436 (1984)) obtained an estimate of D =79030 cm from a low resolution dispersed fluorescence spectrum where levels up to ”=4 could be resolved. In the present work we have used stimulated emission pumping (SEP) to map all of the bound vibrational levels of Be (X). Laser excitation and stimulated emission of the transition of Be has been used in this study. Rotationally resolved SEP spectra have been recorded for ground state vibrational levels ”=1-10, establishing a dissociation energy of D = 927(5) cm . Rydberg-Klein-Rees (RKR) inversion of the rotation and vibration data has been used to determine an accurate potential energy curve. Comparisons with the results from recent theoretical calculations will also be presented. MI10 15 min 4:21 IONIZATION ENERGY MEASUREMENTS AND SPECTROSCOPY OF THE BeOBe MOLECULE J. M. MERRITT, V. E. BONDYBEY, and M. C. HEAVEN, Department of Chemistry, Emory University, Atlanta, GA 30322. The Be O cation was observed some fifty years ago in mass spectroscopic studies of vapors above heated beryllium oxide. From temperature and electron energy dependence of the ion abundance, Theard and Hildebrand (JCP 41, 3416 (1964)) deduced a value of -810 kcal/mole for the enthalpy of formation of neutral Be O in the gas phase. Such strong bonding of the second Be atom to BeO was, at the time, somewhat surprising given the initial view of a double bond in BeO, such that Be donates two electrons and the O atom would have a filled valence shell. More recent electronic structure calculations have shown that the bonding of BeO is intermediate between a single and double bond and thus can form a strong bond with a second Be atom. Calculations have also predicted that the ground electronic state of BeOBe is multi-reference in nature, thus accurate characterization of this molecule can be used to benchmark high-level multiconfigurational theoretical methods. The electronic structure of the BeOBe molecule has been investigated using laser induced fluorescence (LIF) and resonance enhanced multiphoton ionization (REMPI) tenchniques in the 27000-33000 cm range. The BeOBe molecule has been stabilized in the gas phase using pulsed laser vaporization of Beryllium metal, and subsequent free jet expansion into vacuum. Vibrational progressions assigned to excitations of the symmetric and antisymmetric stretches in the excited state are observed and analyzed. Rotationally resolved spectra are found to exhibit nuclear spin statistics which confirm the ground electronic state of BeOBe has symmetry. A BeO bond length of 1.399(3) Angstrom has been determined for the ground state. Photoionization efficiency curves were also recorded to determine an accurate ionization energy for BeOBe of 8.12(1) eV. Comparisons with electronic structure calculations will also be presented. 111 MI11 15 min 4:38 DETERMINATION OF THE IONIZATION AND DISSOCIATION ENERGIES OF MOLECULAR HYDROGEN, H JINJUN LIU, URS HOLLENSTEIN, and FR ÉDÉRIC MERKT, Laboratorium f ür Physikalische Chemie, ETH-Zürich, 8093 Z ürich, Switzerland; EDCEL J. SALUMBIDES, JEROEN C. J. KOELEMEIJ, KJELD S. E. EIKEMA, and WIM UBACHS, Laser Centre, Department of Physics and Astronomy, Vrije Universiteit, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands. The transition wave number from the - (1 ) energy level of ortho-H to the 54 ) ground state of ortho-H has been measured to be Rydberg state below the ( 1 25209.99756(0.00022) (0.00007) cm . Combining this result with previous experimental and theoretical results for other energy level intervals, the ionization and dissociation energies of the hydrogen molecule have been determined to be 124417.49113(37) cm and 36118.06962(37) cm , respectively, which represents a precision improvement over previous experimental and theoretical results by more than one order of magnitude. The new value of the ionization energy can be regarded as the most precise and accurate experimental result of this quantity, whereas the dissociation energy is a hybrid experimental-theoretical determination. MI12 PHOTOELECTRON SPECTROSCOPY AND DYNAMICS OF ICN 15 min 4:55 ELISA M. MILLER, LEONID SHEPS, and W. CARL LINEBERGER, JILA, Department of Chemistry and Biochemistry, University of Colorado at Boulder, Boulder, CO 80309. We report the photoelectron spectrum of ICN and preliminary UV photodissociation studies of ICN . Because CN behaves like a pseudo-halogen, we compare our results to previous spectroscopic and dynamical work on dihalides, such as I , IBr , and ICl . The photoelectron spectrum of ICN resembles that of IBr with transitions to the ground electronic state and two excited states. The transition to the ground electronic state of ICN is broad (FWHM 0.75 eV) and structureless which corresponds to accessing high lying vibrational states. Transitions to the excited states are narrow and spaced by 0.13 eV. A complete analysis of the photoelectron spectrum is underway to determine the structure and energetics of ICN and neutral ICN. In addition, preliminary nanosecond studies of ICN UV photodissociation are reported. In these two-photon experiments, one photon dissociates ICN and the second photon detects anionic products via photoelectron spectroscopy. Following excitation (4 = 260 nm) to a dissociative electronic state of ICN , we observe two anionic photoproducts: I and CN . The presence of both photoproducts could be a result of a non-adiabatic transition midway through photodissociation or excitation to two different anionic states which asymptotically correlate to distinct products. Currently, time-resolved photoelectron studies are underway to determine the actual dissociation pathway. This research is being funded by NSF and AFOSR. 112 MI13 THEORETICAL STUDIES OF TIME-RESOLVED PHOTOELECTRON SPECTRA OF IBr 15 min 5:12 SAMANTHA HORVATH, ANNE B. McCOY, and RUSSELL M. PITZER, Department of Chemistry, The Ohio State University, Columbus, OH 43210. In the present study, we examine the time-resolved photoelectron spectra of IBr . In the photodetachment studies performed by Sanov and co-workers and Lineberger and co-workers, a the anionic species, prepared in its electronic ground state ( ), is excited to either its à ( ) or B̃ ( ) excited state, before electron photodetachment and dissociation on the C̃ ( ) or higher-lying excited states of the neutral species, respectively. In this work, we use the electronic structure program Columbus to calculate the six lowest electronic states of IBr and the ten lowest states of IBr at the MR-SO-CISD/aug-cc-pVDZ level of theory/basis, using relativistic core potentials for I and Br. Experimentally determined electronic states of IBr are also used. b Vibrational eigenstates for these electronic states are calculated in a discrete variable representation, c and propagation of the thermally populated X̃-state vibrational wave functions on either the à or B̃ electronic states of the anion is performed using a Lanczos scheme. We then take time-dependent overlaps between these propagated states and the vibrational eigenstates of the neutral surface. Results for IBr show good agreement with the experimental time-resolved spectra. Extensions to IBr (CO ) ( 5 ) will also be discussed. a R. Mabbs, K. Pichugin, and A. Sanov, J. Chem. Phys., 2005, 122, 174305; Leonid Sheps, Elisa M. Miller, and W. C. Lineberger (private communication). b E. Wrede, S. Laubach, S. Schulenburg, A. Brown, E. R. Wouters, A. J. Orr-Ewing, and M. N. R. Ashfold, J. Chem. Phys., 2001, 114(6), 2629. c D. T. Colbert and W. H. Miller, J. Chem. Phys., 1992, 96(3), 1982. MI14 15 min 5:29 TWO PHOTON EXCITATION OF MOLECULAR IODINE. AN ADVANCED LASER TECHNIQUE FOR THE UNDERGRADUATE PHYSICAL CHEMISTRY LAB W. BRYAN LYNCH, MEGAN J. GOOTEE, and MARC P. CHAVEZ, Department of Chemistry, University of Evansville, Evansville, IN 47722. The iodine molecule is routinely studied in the undergraduate physical chemistry lab and provides practical experiments for topics such as chemical kinetics, phase equilibrium, and electronic molecular structure. In an effort to improve and modernize the physical chemistry lab, many of these experiments now incorporate the use of lasers; for instance, a laser can quite easily be used as the light source for iodine emission and fluorescence quenching experiments. To introduce the use of multiple-laser techniques, and to further the study of iodine in the undergraduate teaching lab, we have developed a double resonance method for accessing the ion-pair states of iodine using a relatively inexpensive nitrogen-pumped dye laser. Iodine is pumped to the B state with the dye laser, followed by excitation to the E and f states with a small portion of the nitrogen beam reflected off the parent beam by a quartz window. The strongest emission to the B state occurs from the f state, and progressions of up to 30 vibrational bands are observed. By varying the energy of the dye laser, we are able to pump vibrational levels of the f state from v=0 up to at least v=17. Analysis of our spectra is complicated by the presence of hot bands and by the relatively large bandwidth of our laser. Even so, we are able to adequately assign most spectral bands and their intensities with the aid of Franck-Condon calculations. 113 MI15 10 min 5:46 FOURIER-TRANSFORM SPECTROSCOPY OF I (- ) EMISSION FOLLOWING OPTICAL-OPTICAL DOUBLE RESONANCE EXCITATION OF THE I ( ) STATE VADIM A. ALEKSEEV, Institute of Physics, St.Petersburg State University, Peterhof, 198504 Russia; AMANDA J. ROSS, Laboratoire de Spectrométrie Ionique et Moléculaire, Université’ de Lyon (Lyon 1), 69622 Villeurbanne, France. The 0 ion-pair state of I molecule may be excited by the optical-optical double resonance (OODR) via the valence state 0 , I ( 0 ) + #1 I ( 0 ) + #1 I ( 0 ). Emission spectra of pure I vapor selectively excited in this way show not only ransitions from the 0 state, but also transition in the near ultraviolet. Typically the populated levels in the 0 state are located less than 300 0 0 cm below the laser-excited level. In this contribution we examine rotationally resolved Fourier-transform spectra of the 0 0 emission following OODR excitation of various 0 1 & levels with single mode cw dye lasers. We show that the 0 0 population transfer obeys the & =& 1, 3, 5 ... propensity rule. Transfer to the & =& 1 levels is the most probable although in some cases, & =& -1 and & =& +1 have significantly different populations. 114 MJ. MATRIX/CONDENSED PHASE MONDAY, JUNE 22, 2009 – 1:30 PM Room: 2015 McPHERSON LAB Chair: WOLFGANG ERNST, Technische Universität Graz, Graz, Austria MJ01 15 min 1:30 OPTICALLY-DETECTED MAGNETIC RESONANCE OF ALKALI ATOMS ISOLATED ON HELIUM NANODROPLETS MARKUS KOCH, CARLO CALLEGARI, WOLFGANG E. ERNST, Institute of Experimental Physics, TU Graz, Petersgasse 16, 8010 Graz, Austria. Sharp, hyperfine-resolved, ESR spectra of alkali atoms isolated on helium nanodroplets are measured by optically-detected magnetic resonance (ODMR). A net spin polarization is created inside a magnetic field ( % to % T) by a pump laser beam. Microwave radiation in a resonant cavity at % GHz causes a spin transition which is detected by a probe laser beam. For ultimate precision the spectrum of free atoms is concurrently measured and serves as a reference. The shift of the ESR lines on the droplet with respect to free atoms directly reflects the distortion of the valence-electron wavefunction due to the He nanodroplet. While the electron . -factor remains unchanged within experimental uncertainties (5 ppm), the increase of the hyperfine constant (typically ppm) is consistent with an increase of the Fermi contact interaction. We are able to follow this change as a function of droplet size attesting the sensitivity of the method for the measurement of chemical shifts. The observation of Rabi oscillations indicates a long decoherence time and proves our ability to perform coherent manipulation of the spin. MJ02 15 min 1:47 HELIUM NANODROPLET ISOLATION SPECTROSCOPY USING AN EXTERNAL CAVITY QUANTUM CASCADE LASER ALEX MORRISON and GARY E. DOUBERLY, Department of Chemistry, University of Georgia, Athens, Georgia 30602. A mode-hop free tunable external cavity quantum cascade laser (Daylight Solutions) is used to probe the vibrational dynamics of helium solvated H O and NO monomers and dimers. The demonstrated high output power and mode-hop free tuning of the laser in combination with a multipass cell and bolometric detection allow for high resolution spectroscopy studies of helium solvated molecules between 10 and 5 m. MJ03 15 min 2:04 ROTATIONAL SPECTROSCOPY OF CARBON MONOXIDE SOLVATED WITH PARA-HYDROGEN MOLECULES PAUL L. RASTON AND WOLFGANG JÄGER, Department of Chemistry, University of Alberta, Edmonton, Alberta T6G-2G2, Canada. Rotational spectra of carbon monoxide ( C O and C O) solvated with N=2 to 7 para-hydrogen (pH ) molecules were studied by high resolution Fourier transform microwave spectroscopy. Infrared spectra of (pH )N -CO clusters have previously been reported by Moroni et al. a . It is expected that the end-over-end rotational frequency decreases from N=2 to N=6, then increases with the addition of the next several helium atoms; this could indicate a significant decoupling of pH density from CO rotation. By measuring the microwave transitions of these clusters we are able to separate the rotational and vibrational contributions to the rovibrational line positions. The trend of the pure rotational frequencies with increasing N-value will be presented. a S. Moroni, M. Botti, S. De Palo, A. R. W. McKellar, J. Chem. Phys., 122, 094314 (2005). 115 MJ04 15 min 2:21 ROVIBRATIONAL SATELLITE BANDS OF THE Br SPIN-ORBIT TRANSITION IN Br DOPED SOLID PARAHYDROGEN DAVID T. ANDERSON, Department of Chemistry, University of Wyoming, Laramie, WY 82071-3838. In the isolated atom the Br spin-orbit (SO) transition is electric-dipole-forbidden because this transition ( P P ) does not involve a change in parity. The isolated Br SO transition therefore acquires intensity from magnetic-dipole and electric-quadrupole terms in the atom-field interaction Hamiltonian and this makes this transition inherently weak. Nonetheless, the Br SO transition is observed in Br-atom doped solid parahydrogen (pH ) crystals prepared at liquid helium temperatures. It will be shown that the intensity of the Br SO transition is greater when isolated in solid pH due to weak intermolecular interactions of the Br atom with the pH matrix. The small increase in the Br SO transition strength results because the Br atom resides in a single substitution site of the hexagonal closed packed pH crystal which lacks a center of inversion. In addition, a vibrational satellite absorption is detected shifted to higher energy by one quantum of H vibration. This vibrational satellite absorption is stronger than the pure SO transition because simultaneous excitation of the Br SO and H vibrational excitation in the pair gives even greater electric-dipole character to the transition. IR spectral evidence for rotational, vibrational, and rovibrational satellite bands of the Br SO transition will be presented. The fact that the rotational and vibrational quantum states of the H molecule are conserved in solid pH accounts for why these satellite absorptions come at well-defined discrete frequencies. The frequencies and lineshapes of these satellite absorptions provide detailed information on the SO state dependent Br-H intermolecular potential. MJ05 15 min 2:38 INVESTIGATION OF THE AMIDE I BAND OF N-METHYLACETAMIDE IN SOLID PARAHYDROGEN USING FTIR SPECTROSCOPY LEIF O. PAULSON and DAVID T. ANDERSON, Department of Chemistry, University of Wyoming, Laramie, WY 82071-3838. We report the FTIR spectra of the Amide I and Amide A vibrational modes of N-methylacetamide (NMA, CH CONHCH ) isolated in a solid parahydrogen (pH ) matrix. NMA is one of the simplest molecules that contains the peptide bond and has therefore been the subject of numerous studies, especially those concerning peptide structure and dynamics. Solid pH is a unique quantum solid matrix host that, among other features, allows for high-resolution IR studies of trapped dopant species. In our preliminary report, a we showed that the Amide I lineshape was surprisingly broad and shifts were observed with small changes in temperature. That talk did not resolve the origin of these shifts with temperature that require many minutes to fully equilibrate. Further investigations have revealed that the frequency and breadth of the transition depends partially on the orthohydrogen concentration in the matrix. The Amide I lineshape displays both reversible and irreversible components that are dependent upon the temperature of the host matrix. This talk will discuss possible explanations for the breadth and temperature dependence of the Amide I feature of NMA isolated in solid pH . a L. O. Paulson and D. T. Anderson, 61st Ohio State University International Symposium on Molecular Spectroscopy, talk R008 (2006) MJ06 CARS STUDY OF LIQUID PARA-HYDROGEN AT DIFFERENT TEMPERATURES 15 min 2:55 RUSSELL SLITER, MICHAEL MAKRIS and ANDREY F. VILESOV, Department of Chemistry, University of Southern California, Los Angeles, CA 90089. Vibrational and rotational spectra of liquid para-H at temperature T = 14 - 26 K and at pressures less than 25 bar have been obtained using coherent anti-Stokes Raman scattering technique. The spectra in solid para-H have also been measured at T = 6 - 13 K. The vibrational frequency in the liquid increases with temperature by about 2 cm , and the shift scales with the square of the density of the sample. An extrapolation of the vibrational frequency in metastable para-H liquid below the freezing point is discussed. The results of this study indicate that the vibron hopping between the molecules is active in the liquid, similar to that previously found in the solid. 116 MJ07 10 min 3:12 ROTATION AND MATRIX EFFECTS ON THE EPR SPECTRA OF METHYL RADICALS TRAPPED IN GAS SOLIDS YURIJ A. DMITRIEVa , Ioffe Physical-Technical Institute, 26 Politekhnicheskaya str.,194021 St. Petersburg, Russia; and NIKOLAS-PLOUTARCH BENETIS, Department of Pollution Control, Technological Educational Institution, TEI, West Macedonia, Kozani 501 00, Greece. A study is presented on EPR spectra of methyl radicals, CH , matrix-isolated in gas solids at liquid helium temperatures. It was shown very recently b that the peculiar features of the trapped methyl rotor are attributed to the quantum effects of inertial rotary motion and its coupling to the nuclear-spin of the radical. Here, we report an investigation of the spectrum saturation behaviour and present a qualitative consideration of the spectrum anisotropy found earlier. However the broadening is by far smaller than in the expected powder of a fully anisotropic radical with rhombic #6 -interaction and . -tensor anisotropy in the solid state. It is present as an asymmetric lineshape of the basic lowest rotational level EPR quartet with cross-relaxation due to the combination of the above mentioned hf interaction with the anisotropic Zeeman one. Splitting of the relatively sharp lines is also observed due to these interactions as well as due to the superimposition of the spectra of the CH radical in other possible sites and/ or defects of the solid Kr-matrix, as well as from the first nontrivial rotational level. This is actually the only indication of the matrix interaction with the methyl radical which seems otherwise to perform almost free rotation in the voids of the more or less “inert” matrix. Of course the basic reason for this behaviour is partially due to the insufficient transfer of thermal energy from the “lattice” to the radical motional degrees of freedom at these low temperatures of the experiments, between 1.5 and 5 K. We give prove that the anisotropy is governed, for the most part, by the repulsion interaction between the CH radical and a matrix particle, while a matrix shift of the methyl hyperfine coupling constant is linked to both the repulsion and the attraction interactions. a Support b Nikolas by Russian Foundation for Basic Research under grant 08-02-90409-Ukr a is gratefully acknowledged P. Benetis and Yurij Dmitriev J. Phys.: Condens. Matter 21(10), 103201 March 2009. Intermission MJ08 10 min 3:40 SPECTROSCOPY OF THE I MOLECULE IN CRYOGENIC MATRICES OF FLUORINE CONTAINING MOLECULES. VADIM A. ALEKSEEV a , Insititute of Physics, St.Petersburg State University, 198504 St.Petersburg, Russia; CHRISTINE PRENDERGAST, JOHN G. McCAFFREY, Department of Chemistry, National University of Ireland, Maynooth, Ireland. The spectroscopy of the I molecule in CF , C F , C F and C F cryogenic solids was studied for the first time with use of steady-state one photon excitation in the Vac UV region and two photon laser excitation. In this contribution we discuss spectra and temporal behaviour of emission originating from the ion-pair states of I . Preliminary results for some other molecular matrices will be presented as well. a Support by Science Foundation of Ireland via Walton Visitor Award (07/W.1/I1819) is gratefully acknowledged 117 MJ09 15 min 3:52 CHARACTERIZATION OF A WATER-HEXAFLUOROBENZENE COMPLEX USING MATRIX ISOLATION INFRARED SPECTROSCOPY JAY C. AMICANGELO, DANIEL G. IRWIN, CYNTHIA J. LEE, and NATALIE C. ROMANO, NANCY L. SAXTON, School of Science, Penn State Erie, Erie, PA 16563. Matrix isolation infrared spectroscopy was used to characterize a 1:1 complex of water (H O) with hexafluorobenzene (C F ). Co-deposition experiments with H O and C F were performed at 17 K using nitrogen and argon as the matrix gases. New infrared bands attributable to the H O-C F complex were observed near the asymmetric stretching, symmetric stretching, and bending vibrations of the water monomer and near the C-F and C-C stretching vibrations of the C F monomer. Identification of the new infrared bands to those of the complex were established by comparing the co-deposition spectra with the spectra of the individual monomers, by performing experiments with isotopically labeled water (D O and HDO), and by matrix annealing experiments. Theoretical calculations were also performed for the H O-C F complex using ab initio and density functional theory methods. In general, the calculations predict the H O and C F vibrational frequencies in the H O-C F complex to be shifted with respect to the H O and C F monomers by similar magnitudes as to what we observe experimentally, lending support to our assignments. MJ10 VIBRATIONAL OVERTONE SPECTRA OF AND IN CRYOGENIC LIQUIDS 15 min 4:09 MARIA H. DIEZ-Y-RIEGA and CARLOS E. MANZANARES, Department of Chemistry and Biochemistry, Baylor University, Waco, Texas, 76798. Vibrational overtone spectra of and in cryogenic solutions were recorded between 5000 and 14000 cm . Spectral regions for the first four overtones were measured using a Fourier transform spectrophotometer. The fifth overtone spectra between 15,000 and 16,000 cm were recorded with a double beam (pump-probe) thermal lens technique using concentrations as low as 10 mole fraction. The peak frequency shift 7 from gas phase to solution is explained by the change in harmonic frequency and anharmonicity in solution with respect to the gas phase values. The bandwidth 7 of the C-H absorption bands in solution can be explained in terms of collisions with the solvent molecules. MJ11 PHOTOCHEMISTRY OF MATRIX-ISOLATED VINYL ACETATE 15 min 4:26 KRISTA COHEN and C. A. BAUMANN, Department of Chemistry, The University of Scranton, Scranton, PA 18510-4626. Vinyl acetate (C H O ) was isolated in matrices of nitrogen, argon, and krypton. The ultraviolet irradiation (45 250 nm) of the matrix results in the formation of a number of products including carbon dioxide, carbon monoxide and ketene (CH CO). Irradiation of the vinyl- C labeled compound yields a mixture of labeled and unlabeled CH CO, CO and CO, indicating that these products arise from the acetyl and the vinoxy moieties. The product C/ C ratios vary with matrix (N 8Ar8Kr). The photolysis efficiency is reduced when the parent compound is deuterated. 118 MJ12 MECHANISM OF THE THERMAL DECOMPOSITION OF FURAN 15 min 4:43 ANGAYLE VASILIOU, G. BARNEY ELLISON, University of Colorado, Boulder, CO 80309-0215; MARK R. NIMLOS, Center for Renewable Chemical, Technologies & Materials, NREL, 1617 Cole Blvd., Golden, CO 80401; JOHN W. DAILY, Department of Mechanical Engineering, University of Colorado, Boulder, CO 80309-0427. Both furan (C H O) and furfural (C H O-CHO) are important products in biomass pyrolysis. We have used a resistivelyheated SiC tubular reactor with a 30 microseconds residence time to study the thermal cracking of furan. The decomposition products are identified by two independent techniques: 118.2 nm VUV photoionization mass spectroscopy and infrared spectroscopy. We observe three different thermal dissociation channels leading to: a) CH CCH + CO b) HCCH + CH CO c) HCCCH . MJ13 15 min 5:00 MILLIMETER-WAVE SPECTRA OF CARBON MONOXIDE SOLVATED WITH HELIUM ATOMS L. A. SURIN, T. F. GIESEN, S. SCHLEMMER, I. Physikalisches Institut, University of Cologne, 50937 Cologne, Germany; A. V. POTAPOV, B. S. DUMESH, Institute of Spectroscopy of Russian Academy of Sciences, 142190 Troitsk, Moscow region, Russia. Millimeter-wave spectra of He CO ( C O, C O, C O, C O) clusters with up to 10, produced in a molecular expansion, were observed using intracavity OROTRON jet spectrometer in the frequency range of 110-150 GHz. The (0) transitions were detected, which correspond to the known *-type (' = 1 0) (0) lines of the binary system, He CO. Further, the -type (' = 0 0) rotational transitions of He CO ( = 7, 8) in the frequency range of 20-40 GHz were measured combining OROTRON spectrometer with a double resonance technique. The isotopic shifts of the cluster transitions show remarkably smooth behavior with from 1 to 6 and become rather scattering for 7. The dependence of the rotational constant (cluster moment of inertia) and of the shift of the CO fundamental vibration on the number of He atoms in cluster were obtained for He CO isotopologues from the analysis of their infrared spectra a and very recent microwave data for the normal He C O isotopologue b . This study explores the microscopic evolution of superfluidity, which becomes apparent even in such small clusters as He CO. The obtained results are compared with those from recent quantum Monte-Carlo calculations c and used to further interpret recent infrared measurements of CO in helium nanodroplets d . a J. Tang, A. R. W. McKellar, J. Chem. Phys. 119, 763 (2003); A. R. W. McKellar, J. Chem. Phys. 121, 6868 (2004); A. R. W. McKellar, J. Chem. Phys. 125, 164328 (2006). b L. A. Surin, A. V. Potapov, B. S. Dumesh, S. Schlemmer, Y. Xu, P. L. Raston, and W. Jäger, Phys. Rev. Lett. 101, 233401 (2008). c T. Škrbić, S. Moroni, and S. Baroni, J. Phys. Chem. A 111, 7640 (2007). d K. von Haeften, S. Rudolph, I. Simanovski, M. Havenith, R. E. Zillich, and K. B. Whaley, Phys. Rev. B 73, 054502 (2006). MJ14 Post-deadline Abstract – Original Abstract Withdrawn 15 min 5:17 HENDI SPECTROSCOPY OF C-H STRETCHING MODES OF METHANE AND SUBSTITUTED METHANE MOLECULES ROBERT R. FEHNEL and KEVIN K. LEHMANN, Department of Chemistry, University of Virginia, Charlottesville VA, 22904-4319. We report the first results with a new Helium Nanodroplet Isolation Spectroscopy machine at UVa. The excitation source is an ARGOS cw PPLN OPO (Aculight). which produces 2 W in the 3.2-3.9 m spectral window. We are extending the spectroscopy of methane in helium, having observed weak, Fermi Resonance induced ro-vibrational transitions of CH and the C-H fundamentals of CH D, CH D , and CHD . We have also observed the spectrum of CH Cl and plan to report on other substituted methane molecules at the conference. 119 TA. MICROWAVE TUESDAY, JUNE 23, 2009 – 8:30 AM Room: 160 MATH ANNEX Chair: VADYM ILYUSHYN, Institue of Radio Astronomy, Kharkiv, Ukraine TA01 GAS PHASE STRUCTURE OF AMINO ACIDS: LA-MB-FTMW STUDIES 15 min 8:30 I. PENA S. MATA, M. E. SANZ, V. VAQUERO, C. CABEZAS, C. PEREZ, S. BLANCO, J. C. L ÓPEZ, and J. L. ALONSO, Grupo de Espectroscopı́a Molecular (GEM), Departamento de Quı́mica Fı́sica y Quı́mica Inorgánica, Facultad de Ciencias, Universidad de Valladolid, E-47005 Valladolid, Spain. Recent improvements in our laser ablation molecular beam Fourier transform microwave (LA-MB-FTMW) a spectrometer such as using Laval-type nozzles b and picoseconds Nd:YAG lasers (30 to 150 ps) have allowed a major step forward in the capabilities of this experimental technique as demonstrated by the last results in serine c cysteined and threonine for which seven, six and seven conformers have been respectively identified. Taking advantage of these improvements we have investigated the natural amino acids metionine, aspartic and glutamic acids and the -aminobutyric acid (GABA) with the aim of identify and characterize their lower energy conformers. Searches in the rotational spectra have lead to the identification of seven conformers of metionine, six and five of aspartic and glutamic acids, respectively, and seven for the -aminobutyric. These conformers have been unambiguously identified by their spectroscopic constants. In particular the N nuclear quadrupole coupling constants, that depend heavily on the orientation of the amino group with respect to the principal inertial axes of the molecule, prove to be a unique tool to distinguish unambigously between conformations with similar rotational constants. For the -aminobutyric acid two of the seven observed structures are stablized by an intramolecular interaction n-$ *. Two new conformers of proline have been identified together with the two previously observed. e a J. L. Alonso, C. Pérez, M. E. Sanz, J. C. López, S. Blanco, Phys.Chem.Chem.Phys., 2009, 11, 617. B. Atkinson, M. A. Smith, Rev. Sci. Instrum. 1995, 66, 4434. c S. Blanco, M. E. Sanz, J. C. López, J. L. Alonso, Proc. Natl. Acad. Sci. USA2007, 104, 20183. d M. E. Sanz, S. Blanco, J. C. López, J. L. Alonso, Angew. Chem. Int. Ed.,2008, 120, 6312. e A. Lesarri, S. Mata, E. J. Cocinero, S. Blanco, J.C. López, J. L. Alonso, Angew. Chem. Int. Ed. , 2002, 41, 4673 b D. TA02 PROBING GUANINE AND CYTOSINE TAUTOMERS IN THE GAS PHASE 15 min 8:47 I. PENA, V. VAQUERO, J. C. LÓPEZ, and J. L. ALONSO, Grupo de Espectroscopı́a Molecular (GEM), Departamento de Quı́mica Fı́sica y Quı́mica Inorgánica, Facultad de Ciencias, Universidad de Valladolid, E-47005 Valladolid, Spain. Using laser ablation molecular beam Fourier transform microwave spectroscopy (LA-MB-FTMW) we have recently studied the nucleic acid bases uracil a and thymine. b We have now successfully probed in isolation conditions in the gas phase cytosine and guanine which are solids with high melting points (m.p.8300C) and a low vapour pressure, and consequently, they are elusive to gas-phase rotational studies. Five rotational species have been detected in the supersonic expansion of cytosine. The unambiguous assignment of the observed species to the various tautomer/conformer structures is based on the markedly different values of the quadrupole coupling constants of the three N nuclei, which act as fingerprints for the identification of the various species. Four species have been observed in the rotational spectra of Guanine. The comparison between the experimental rotational constants and those calculated ab initio provide a definitive test for the identification of the four lowest energy forms. The planarity of the tautomers is discussed on the basis of the inertial defect values (=I -I -I ). a V. Vaquero, M.E. Sanz, J.C. López and J.L. Alonso, J. Phys. Chem. A 111, 3443 (2007) López, M.I. Peña, M.E. Sanz and J.L. Alonso, J. Chem. Phys. 126, 191103 (2007) b J.C. 120 TA03 ROTATIONAL SPECTRA OF PHENYLALANINE, TIROSINE AND TRYPTOPHAN 15 min 9:04 S. MATA, C. PEREZ, M. E. SANZ, S. BLANCO, J. C. L ÓPEZ, and J. L. ALONSO, Grupo de Espectroscopı́a Molecular (GEM), Departamento de Quı́mica Fı́sica y Quı́mica Inorgánica, Facultad de Ciencias, Universidad de Valladolid, E-47005 Valladolid, Spain. The rotational spectra of the aromatic natural amino acids phenylalanine, tyrosine and tryptophan have been investigated by Laser Ablation Molecular Beam Fourier transform Microwave Spectroscopy LA-MB-FTMW. The spectra of two rotamers of phenylalanine have been detected in the supersonic expansion. Both forms are stabilized by a chain of intramolecular hydrogen bonds O-H N-H $ , being the carboxylic group incis configuration. One conformer of tyrosine, which only differs from phenylalanine in a -OH group inpara position, has been also characterized. Preliminary results on the rotational spectrum of tryptophan are presented. TA04 15 min 9:21 THE STUDY OF SMALL BIOMOLECULES USING CHIRPED-PULSE FOURIER TRANSFORM MICROWAVE (CPFTMW) SPECTROMETER IN THE GAS PHASEa RYAN G. BIRD and DAVID W. PRATT, Department of Chemistry, University of Pittsburgh, Pittsburgh, Pa 15213; JUSTIN L. NEILL and BROOKS H. PATE, Department of Chemistry, University of Virginia, Charlottesville, Va 22904. The microwave spectra of a large molecule is sensitive to both the structure of the molecule and as well as its motion along different vibrational coordinates. Chirped-pulse Fourier transform microwave (CP-FTMW) spectroscopy is an exciting new technique that makes possible the reading of the complete microwave spectrum of a gas phase sample using a single 1 s pulse. In this report, we will describe the recent introduction of a laser ablation nozzle for the study of small biomolecules using this technique. Potential applications of the technique to other samples also will be described. a Work supported by NSF (CHE-0618740). TA05 15 min 9:38 CHIRPED PULSE-FOURIER TRANSFORM MICROWAVE SPECTROSCOPY OF ETHYL 3-METHYL-3PHENYLGLYCIDATE (STRAWBERRY ALDEHYDE) STEVEN T. SHIPMAN, Department of Natural Sciences, New College of Florida, Sarasota, FL; JUSTIN L. NEILL, MATT T. MUCKLE, RICHARD D. SUENRAM, and BROOKS H. PATE, Department of Chemistry, University of Virginia, Charlottesville, VA 22904. Strawberry aldehyde (C O H ), a common artificial flavoring compound, has two non-interconvertible conformational families defined by the relative stereochemistry around its epoxide carbons. In one family, referred to as the trans because the two large substituents (a phenyl ring and an ethyl ester) are on opposite sides of the epoxide ring, these two substituents are unable to interact with each other. However, in the cis family, there is a long-range interaction that is difficult to accurately capture in electronic structure calculations. Three trans and two cis conformations have been assigned by broadband chirped pulse Fourier transform microwave spectroscopy, along with the C-13 isotopomers in natural abundance for one conformer from each of the families. The agreement of the rotational constants, relative dipole moments, and relative energies between theory and experiment is excellent, even at relatively crude levels of theory, for the trans family, but is quite poor for the cis conformers. In addition, due to the reactivity of strawberry aldehyde and the high temperature to which it must be heated to yield a suitable vapor pressure, several decomposition products have been assigned, and more, as of yet unassigned, are likely to be present. This project demonstrates some of the challenges in performing large-molecule rotational spectroscopy. 121 TA06 THE ROTATIONAL SPECTRUM OF TERTIARY-BUTYL ALCOHOL 15 min 9:55 E. A. COHEN, B. J. DROUIN, Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109-8099; E. A. VALENZUELA a, R. C. WOODS, Department of Chemistry, University of Wisconsin, Madison WI 53706-1322; W. CAMINATI, A. MARIS, and S. MELANDRI, Dipartimento di Chimica “G. Ciamician” dell’Università, Via Selmi 2, I-40126 Bologna, Italy. Tertiary-butyl alcohol is a nearly spherical rotor for which the internal rotation axis of the t-butyl group is close to the molecular axis in the ac plane. Methyl group torsional spittings are not observed in the ground state. Its 8 to 40 GHz rotational spectrum was reported at this meeting by Valenzuela and Woods in 1974 b and in more detail in 1975 c. The parameters derived at that time from a fit to the states with & ' d have provided the basis for extending the measurements to 8 GHz. The combined data set extends to & ' 8 and is fit with the program SPFIT e using a common set of parameters for both the and states. The general features of the spectrum and the fitting procedure will be described. The resulting molecular constants and their interpretation will be discussed. a Present address, 4901 Oakridge Dr. Midland, MI 48640-1919 Valenzuela, and R. C. Woods, Abstract MF6, International Symposium on Molecular Spectroscopy, Columbus, OH, 1974 c E.A. Valenzuela, and R. C. Woods, Abstract RG15, International Symposium on Molecular Spectroscopy, Columbus, OH, 1975 d E.A. Valenzuela, Ph.D. Thesis, University of Wisconsin-Madison, 1975. e H. M. Pickett, J. Mol. Spectrosc. 148 (1991) 271-377. b E.A. Intermission TA07 15 min MICROWAVE SPECTROSCOPIC MEASUREMENTS OF THE ROTATIONAL SPECTRUM OF METHYL CYCLOPENTADIENYL IRON DICARBONYL 10:30 CHAKREE TANJAROON and STEPHEN G. KUKOLICH a , Department of Chemistry, The University of Arizona, Tucson, Arizona 85721. The rotational spectra of the methyl cyclopentadienyl iron dicarbonyl complex (namely methyl-Fip) were measured using a pulsed molecular beam Fourier transform microwave spectrometer. Methyl-Fip is an asymmetric top complex with a single methyl rotor bound to iron. The complex is challenging to study experimentally in the gas phase because it is unstable and exhibits methyl internal rotation. We report here the first measurements of the a-type rotational spectrum and determination of a methyl torsional barrier height. Analysis of the observed doublet splittings of low J and K lines yielded a barrier height of 8.7(8) kJ. The observed rotational constants for the parent ( - 0) complex are = 1431.74(13), = 1062.263(84), and = 828.016(15) MHz. Assignment of the measured rotational spectrum, quantum chemical calculations, and the molecular structure of methyl-Fip will be discussed. a Support by NSF research grant is gratefully acknowledged 122 TA08 MICROWAVE STUDIES OF PERFLUOROPENTANE AND ITS HELICITY 15 min 10:47 JOSEPH A. FOURNIER, ROBERT K. BOHN, Dept. of Chemistry, Univ. of Connecticut, Storrs, CT 062693060; JOHN A. MONTGOMERY, JR., Dept. of Physics, Univ. of Connecticut, Storrs, CT 06269-3046. Unlike hydrocarbons, fluorocarbons are helical in their all-trans most stable conformations. A definitive experimental determination of the helical angle has not been accomplished because single crystal X-ray studies are not available due to the lack of suitable crystallization solvents, but a value of Æ from exactly trans is generally accepted from X-ray fiber studies. Using a pulsed-jet Fourier Transform microwave spectrometer, we have observed and assigned the rotational spectra of the lowest energy all-anti C symmetry form of perfluoro-n-pentane and all three of its C isotopomers. A, B, and C values of the parent species are 990.6394(4) MHz, 314.00020(14) MHz, and 304.37034(14) MHz, respectively. A range of effective r structures incorporating various model constraints are consistent with about Æ torsion and a Kraitchman analysis of the parent and C species gives %Æ . Ab initio calculations are consistent with the experimental results. TA09 15 min 11:04 ANALYSIS OF THE ROTATIONAL SPECTRA OF 2,3,4,5,6-PENTAFLUOROTOLUENE AND 1-CHLORO-2,3,4,5,6PENTAFLUOROBENZENE ASHLEY A. OSTHOFF, REBECCA A. PEEBLES, SEAN A. PEEBLES, Department of Chemistry, Eastern Illinois University, 600 Lincoln Ave., Charleston, IL 61920; GARRY S. GRUBBS II, STEPHEN A. COOKE, Department of Chemistry, University of North Texas, PO Box 305070, Denton, TX 76203; BROOKS H. PATE, JUSTIN L. NEILL, MATT T. MUCKLE, Department of Chemistry, University of Virginia, McCormick Rd., PO Box 400319, Charlottesville, VA 22904. The microwave spectra of two substituted pentafluorobenzenes have been obtained. 2,3,4,5,6-Pentafluorotoluene was measured using the FTMW spectrometer at Eastern Illinois University and the chirped-pulse FTMW spectrometer at University of North Texas. The heavy atom structure has been obtained from the assigned C transitions and is in reasonable agreement with ab initio calculations at the MP2/6-311++G(2d, 2p) level. The ground state rotational constants are % MHz, % MHz, and % MHz, and the single dipole moment component is % D. Very small splittings for many of the assigned transitions and multiple, as yet unassigned, lines were presumably due to excited torsional states of the methyl group. In a related study, the microwave spectrum of 1-chloro-2,3,4,5,6-pentafluorobenzene was obtained for both the Cl and the Cl isotopologues using the chirped-pulse microwave spectrometer at University of Virginia. The preliminary ground state rotational constants for this compound are % MHz, % MHz and % MHz for Cl and % MHz, % MHz and % MHz for Cl. Initial fits of the nuclear quadrupole coupling constants give , % MHz, , % MHz, , % MHz for the Cl species and , % MHz, , % MHz, , % MHz for the Cl species. These results will be compared with pentafluorotoluene to observe the effects on the structure of the benzene ring when substituting a chlorine atom for a methyl group. 123 TA10 15 min 11:21 THE DIFFERENCES IN THE ROLE OF O AND S ATOMS IN THE MOLECULAR STRUCTURE AND DYNAMICS OF SOME COMPLEXES YOSHIYUKI KAWASHIMA, AKINORI SATO and YOSHIO TATAMINTANI, Department of Applied Chemistry, Faculty of Engineering, Kanagawa Institute of Technology, Atsugi, Kanagawa 243-0292, JAPAN; NOBUKIMI OHASHI, Kanazawa University, 920-1192, JAPAN; JAMES M. LOBUE, Department of Chemistry, Georgia Southern University, Statesboro, GA 30460, USA; EIZI HIROTA, The Graduate University for Advanced Studies, Hayama, Kanagawa 240-0193, JAPAN. We have investigated the van der Waals complexes consisting of the one among a rare gas atom (Rg), CO, N or CO combined with one of the two pair molecules: dimethyl ether (DME)/ dimethyl sulfide (DMS) and ethylene oxide (EO)/ ethylene sulfide (ES), by using Fourier transform microwave spectroscopy supplemented by * 9 99 MO calculations, in order to examine how different the role of the O and S atoms is in molecular properties of the complexes. The present talk reports the results on Ar-DMS and CO-EO, in comparison with those on Ar-DME and CO-ES, respectively. For the CO-EO complex, we concluded the CO moiety located in a plane perpendicular to the C-O-C plane and bisecting the COC angle of EO, in sharp contrast with the case of CO-DME, where the heavy atoms lie essentially in a same plane. a An * 9 99 MO calculation at the level of MP2/6-311++G(,) yielded a structure, which, when optimized, agreed well with the experimental result for the both complexes. The molecular structures of the pair molecules DME/DMS and EO/ES resemble with each other. However, van der Waals complex formation of these pair molecules with either Rg or CO leads to quite different structures of the complex. In the case of the CO-DMS and CO-ES, the CO moiety is located closer to the CH and CH end of DMS and ES, respectively, whereas to the O end in the cases of CO-DME and CO-EO. Similar differences were found for Rg complexes. Because of the larger atomic radius and lower electronegativity of S than those of O, S behaves as a much weaker nucleophile than O, which explains the differences in molecular structure between the two corresponding complexes. The structures of Rg-DMS and Rg-ES thus considerably deviate from that of the -type complex proposed by Legon. b a Y. b A. Kawashima, Y. Morita, Y. Tatamitani, N. Ohashi, and E. Hirota, 127, 194302 (2007). C. Legon, 38, 2686 (1999). TA11 FOURIER TRANSFORM MICROWAVE SPECTRA OF -BUTANOL AND ISOBUTANOL 15 min 11:38 TAIGO UZUYAMA, YUGO TANAKA, and YOSHIYUKI KAWASHIMA, Department of Applied Chemistry, Faculty of Engineering, Kanagawa Institute of Technology, Atsugi, Kanagawa 243-0292, JAPAN; EIZI HIROTA, The Graduate University for Advanced Studies, Hayama, Kanagawa 240-0193, JAPAN. We have investigated two butanols, normal (1-butanol) and iso (2-methyl-1-propanol), by Fourier transform microwave spectroscopy, focusing attention mainly to internal motion and rotational isomerism. We anticipate that -butanol exists in fourteen rotational isomers with the combination of the following conformations: (: ) and ./#0 (;) with respect to the CH CH -CH CH OH bond, () and two ./#0’s (. , . ’) to the CH CH CH -CH OH bond, and two or three potential minima in the internal rotation of OH, and that isobutanol in five. We scanned the frequency region from 7 to 25 GHz using a heated nozzle, and detected six and three isomers for -butanol and isobutanol, respectively: three with Ar as a buffer gas and three with Ne instead of Ar for -butanol, whereas Ar was employed for isobutanol. The observed spectral lines were assigned by comparing the experimental moments of inertia and the observed spectral intensities with those calculated by * 9 99 MO at the MP2/6-311++G(d,p) level. We thus concluded that five conformers detected for -butanol are : -form and one ;-form and that three observed isomers of isobutanol are ./#0 with respect to the H(CH ) C-CH OH bond and one isomer lacking -type spectra to to the CH -OH bond. 124 TA12 15 min 11:55 ANALYSIS OF THE ROTATIONAL STRUCTURE IN A C-TYPE BAND IN THE HIGH-RESOLUTION INFRARED SPECTRUM OF -1,4-DIFLUOROBUTADIENE-1- NORMAN C. CRAIG, CHRISTOPHER F. NEESE, and DEACON J. NEMCHICK, Department of Chemistry and Biochemistry, Oberlin College, Oberlin, OH 44074; MICHAEL LOCK, Physikalish-Chemisches Institut der Justus Liebig Universität, Heinrich-Buff Ring 58, D-35392, Giessen, Germany. A mixture of deuterium isotopomers of trans,trans-1,4-difluorobutadiene (ttDFBD) was prepared by partial exchange with NaOD/D O. A prominent component of the mixture was the 1-d species. The rotational structure in a C-type band of this species centered at 920.5 cm was analyzed in the high-resolution (0.002 cm ) infrared spectrum. The analysis of this band was compromised by large contributions from a C-type band at 893 cm in the spectrum of ttDFBD-1,4-d . Provisional ground state rotational constants for ttDFBD-1-d are reported. We have recently shown that 1-fluoroethylene can be exchanged with NaOD/D O to give 1-fluoroethylene-1-d , which can be used in known chemistry to make pure DFBD-1-d . An improved high-resolution infrared spectrum of ttDFBD-1-d will be obtained. This method will also yield cis,cis-DFBD-1-d for investigation. Rotational constants for ttDFBD-1-d and ccDFBD-1-d are needed for determining the semi-experimental equilibrium structures of the two nonpolar isomers of DFBD. 125 TB. ELECTRONIC TUESDAY, JUNE 23, 2009 – 8:30 AM Room: 170 MATH ANNEX Chair: MASAAKI BABA, Kyoto University, Kyoto, Japan TB01 15 min 8:30 HIGH RESOLUTION ELECTRONIC SPECTROSCOPY OF 2,6-DIAMINOPYRIDINE IN THE GAS PHASE a CASEY L. CLEMENTS, ADAM J. FLEISHER, JUSTIN W. YOUNG, JESSICA A. THOMAS, AND DAVID W. PRATT, Department of Chemistry, University of Pittsburgh, Pittsburgh, PA 15260. Ab initio calculations suggest that 2,6-diaminopyridine (26DAP) has several interesting low-frequency vibrations arising from motion of its amino groups. For this reason, 26DAP has been studied in the gas phase using both low resolution and high resolution electronic spectroscopy techniques. Presented here are the results of this study, which provide information about the structural and dynamical properties of 26DAP in both the ground and excited electronic states. The results will be discussed. a Work supported by NSF (CHE-0615755). TB02 15 min 8:47 CHARACTERIZATION OF STRUCTURAL ISOMERS OF NAPHTHALENE: ELECTRONIC SPECTROSCOPY OF Z-PHENYLVINYLACETYLENE JOSH J. NEWBY, CHRISTIAN W. MÜLLER, CHING-PING LIUa , WILLIAM H. JAMES III, EVAN G. BUCHANAN, HSIUPU D. LEE, AND TIMOTHY S. ZWIER, Department of Chemistry, Purdue University, West Lafayette, IN 47907. In a variety of contexts from planetary atmospheres to combustion processes, the appearance of C H is commonly attributed to naphthalene. Often neglected are other stable C H isomers that could be formed prior to isomerization to naphthalene, such as phenylvinylacetylene (PVA, 1-phenyl-1-buten-3-yne). The electronic spectroscopy of the E isomer of PVA has already been reported, b but direct isomerization to naphthalene would seem more likely from the Z isomer. Here, we report the jet-cooled laser induced fluorescence and single vibronic level dispersed fluorescence spectra of Z-PVA. The spectra display low frequency vibronic structure reminiscent of that in styrene, attributable to the out-of-plane torsion and bend of the vinylacetylene group. The vibrational assignments are assisted by ab initio calculations and the results are compared with the analogous motions in styrene. Interestingly, the excitation spectrum shows a dramatic decrease in fluorescence intensity about 600 above the electronic origin. This intensity drop off is attributable to a turn on in nonradiative processes. a Current b C. Address: Institute of Chemistry, Academia Sinica, Taipei, 11529 Taiwan. P. Liu, J. J. Newby, C. W. Müller, H. D. Lee, and T. S. Zwier J. Phys. Chem. A. 112, 9454 (2008). 126 TB03 FLUORESCENCE SPECTROSCOPY OF JET-COOLED 1-PHENYL-1-BUTYN-3-ENE 15 min 9:04 JOSHUA A. SEBREE,TIMOTHY S. ZWIER, Department of Chemistry, Purdue University, West Lafayette, IN 47909-2084. With the growing interest in the role naphthalene may play in planetary atmospheres and the interstellar medium, it is important to characterize other C H structural isomers. These C H isomers, once formed, may undergo an isomerization reaction to form naphthalene, or react via alternative pathways that lead away from its formation. The laser induced fluorescence (LIF) and single vibronic level dispersed fluorescence (SVLF) spectra have been collected for the S S transition of the C H isomer 1-phenyl-1-butyn-3-ene. With an S S origin occurring at 34922 cm , the vibronic bands at 464.0 and 530.5 cm above the origin dominate the LIF spectrum giving evidence for strong vibrational coupling in the excited state. The SVLF spectra for more than fifteen vibronic bands in the LIF have been collected. Vibrational assignments were made with assistance from ab initio calculations. Unlike its close structural isomer 1-phenyl-1-buten-3-yne, PAV shows no evidence for a fast non-radiative process within the first 1400 cm above the S origin. TB04 15 min 9:21 HIGH-RESOLUTION THRESHOLD PHOTOIONIZATION AND PHOTOELECTRON SPECTROSCOPY OF PROPENE AND 2-BUTYNE JULIE M. MICHAUD, KONSTANTINA VASILATOU and FR ÉDÉRIC MERKT, LABORATORIUM FÜR PHYSIKALISCHE CHEMIE, ETH ZÜRICH, 8093 ZÜRICH, SWITZERLAND. The high-resolution photoionization and pulsed-field ionization zero-kinetic energy (PFI-ZEKE) photoelectron spectra of propene and 2-butyne and their perdeuterated isotopologues have been recorded in the vicinity of the first adiabatic ionization energy following single-photon excitation from the neutral ground state using a narrowband vacuum ultraviolet laser system. The spectral resolution of better than 0.1 cm achieved in these spectra has enabled us to partially resolve the rotational structure of the photoelectron spectra and to obtain information on the internal rotation/torsional vibration of the methyl groups in the cationic ground state. The intensity distributions observed in the photoelectron spectra will be discussed in terms of rovibronic photoionization selection rules and Franck-Condon factors for transitions between the neutral and ionized molecules. Intermission TB05 15 min 10:00 ACID-BASE ELECTRONIC PROPERTIES IN THE GAS PHASE: PERMANENT ELECTRIC DIPOLE MOMENTS OF A PHOTOACIDIC SUBSTRATE.a ADAM J. FLEISHER, PHILIP J. MORGAN and DAVID W. PRATT, Department of Chemistry, University of Pittsburgh, 15260. The permanent electric dipole moments of two conformers of 2-naphthol (2HN) in their ground and electronically excited states have been experimentally determined by Stark-effect measurements in a molecular beam. When in solution, 2HN is a weak base in the S state and a strong acid in the S state.b Using sequential solvation of the cis-2HN photoacid with the base ammonia, we have begun to approach condensed phase acid-base interactions with gas phase rotational resolution. c Our study, void of bulk solvent perturbations, is of importance to the larger community currently describing aromatic biomolecule and ”super” photoacid behavior via theoretical modeling and condensed phase solvatochromism. a Work supported by NSF (CHE-0615755). Weller. Prog. React. Kinet. 5, 273 (1970). c D. F. Plusquellic, X. -Q. Tan, and D. W. Pratt. J. Chem. Phys. 96, 8026 (1992). b A. 127 TB06 1-PHENYLPYRROLE A TICT MOLECULE?. a 15 min 10:17 JESSICA A. THOMAS, JUSTIN W. YOUNG, ADAM J. FLEISHER, CASEY L. CLEMENTS, and DAVID W. PRATT, Department of Chemistry, University of Pittsburgh, Pittsburgh, PA 15260; LEONARDO ALVAREZ-VALTIERRA, Division de Ciencias e Ingenierias, Campus Leon, Universidad de Guanajuato, Leon, Gto. 37150, Mexico. 1-Phenylpyrrole has been identified by several authors as a molecule that displays twisted intramolecular charge-transfer (TICT) character in the condensed phase. However, Suzuka and coworkers b , using single vibronic level dispersed fluorescence, observed no evidence of TICT activity in the gas phase. In this work, 1-phenylpyrrole is studied by the high resolution methods previously applied to DMABN c to determine the extent of its motion along different possible TICT coordinates when it absorbs light. a Work supported by NSF CHE-0615755 Okuyama, Y. Numata, S. Odawara, and I. Suzuka, J. Chem. Phys., 109, 7185 (1998) and references therein. c A. E. Nikolaev, G. Myszkiewwicz, G. Berden, L. Meerts, J. F. Pfanstiel, and D. W. Pratt, J. Chem. Phys., 122, 084309 (2005). b K. TB07 15 min 10:34 EVOLUTION OF THE MLCT BAND FOLLOWING CHANGES IN OXIDATION STATE FOR HIGHLY COUPLED MIXED VALENCE COMPLEXES BENJAMIN J. LEAR and MALCOLM H. CHISHOLM, The Ohio State University, Department of Chemistry, Columbus, Ohio 43210. The MLCT band for a series of dimers composed of pairs of quadruply bonded metal-metal units ([MM(CH CO ) ] - oxalate; where M=Mo or W) is examined in both the neutral and +1 (mixed valence) states. The MLCT band for the neutral state of these complexes exhibits clear vibronic features that are greatly reduced in intensity upon generation of the mixed valence state. Utilizing the time dependent theory of spectroscopy as developed by Eric Heller, these results (together with Raman spectra and TD-DFT calculations) are used in order to draw conclusions concerning the potential energy surfaces involved in the MLCT transition for these complexes. In particular, we are concerned with changes to the offset of the ground and excited state potential energy surfaces that occur along the coordinates involved in the vibronic coupling and which accompany changes in oxidation state. The insight thus gained is used in order to understand the degree of electronic coupling present in mixed valence species and to comment on the classification of mixed valence complexes. TB08 15 min EFFECTS OF METHYLATION ON ZEBULARINE STUDIED BY DENSITY FUNCTIONAL THEORY 10:51 LALITHA SELVAM, VLADISLAV VASILYEV and FENG WANG, Centre for Molecular Simulation, Faculty of ICT, Swinburne University of Technology, Hawthorn, Victoria 3122,Australia; VLADISLAV VASILYEV, National Computational Infrastructure, Australian National University, Canberra, ACT 0200,Australia (Corresponding email:lselvam@ict.swin.edu.au). 1-() -D-ribofuranosyl)-2-pyrimidone (zebularine or zeb) and 1-() -D-ribofuranosyl)-5-methyl-2-pyrimidinone (d5) are effective inhibitors of cytidine deaminases (CDA). Methyl modification of zeb at the C(5) position in the base moiety produces d5. A density functional theory (DFT) study reveals the impact of the methyl group on the electronic structures and spectra of the nucleoside pair. It is found that the addition of methyl group has little effect on the geometry of the nucleosides as well as their sugar puckering, but affects anisotropic properties such as dihedral angles, condensed Fukui functions and charge distribution can be seen in their molecular electrostatic potentials (MEPs). Electron spectra serve as the fingerprint for the methyl group. The valence spectra clearly indicate that the molecular pair is related in the inner valence space of IP 8 0 , whereas the outer valence space reveals the methyl associated electronic structural modifications of the molecular pair. In the present study, the molecular orbitals (MO) such as MO8, MO18 and MO37 (HOMO as MO1) are identified as the fingerprint MOs for methyl, whereas other MOs marked in the figure are secondary methyl related MOs. Chemical shift in the inner shell and their spectra are also calculated. It reveals the similarities and differences of methyl effect to large nucleosides and small amino acids such as L-alanine. 128 TB09 15 min 11:08 CONFORMATION-SPECIFIC ELECTRONIC AND VIBRATIONAL SPECTROSCOPY OF DIBENZO-15-CROWN-5 ETHER IN A SUPERSONIC JET. EVAN G. BUCHANAN, CHIRANTHA P. RODRIGO, WILLIAM H. JAMES III, JOSH J. NEWBY, and TIMOTHY S. ZWIER, Department of Chemistry, Purdue University, West Lafayette, IN 47907. Crown ethers are oxygen containing cyclic structures noted for their ability to preferentially bind substrates such as ions and water. Despite the high symmetry inherent to the chemical structure, crown ethers are remarkably flexible, adapting their conformation to the substrate to which they are bound. As such, it is valuable to study the conformational preferences of the isolated crown ethers in the absence of any substrate. Here, we present the electronic and infrared spectroscopy of jet-cooled, isolated dibenzo-15-crown-5 ether (DB15C). By incorporating two phenyl rings into the crown, we are afforded the opportunity to explore the ultraviolet spectroscopy of both groups and the coupling between them. One-color resonant two-photon ionization, laser induced fluorescence, UV-UV holeburning, and resonant ion-dip infrared spectroscopies are used to provide conformation-specific electronic and infrared spectra of the three conformers. Additionally, single vibronic level dispersed fluorescence spectra provide evidence for the existence of close lying S states in the two major conformers, located about 527 cm above their S counterparts. Based on a comparison with benzo-15-crown-5 ether, we surmise that the local conformation of the ethoxy groups about the two phenyl rings are different. Electronic energy transfer appears to be slow between these phenyl rings on the timescale of the excited state fluorescence. Finally, DFT and MP2 calculations will be presented as a basis for tentative structural assignments and provide insight into the excitonic coupling of the two chromophores. TB10 15 min 11:25 WATER’S ROLE IN RESHAPING A MACROCYCLE’S BINDING POCKET: CONFORMATION-SPECIFIC INFRARED AND ULTRAVIOLET SPECTROSCOPY OF BENZO-15-CROWN-5- -CLUSTERS V. ALVIN SHUBERT, Argonne National Laboratory, Chemical Sciences and Engineering Division, 9700 South Cass Avenue, Argonne, IL 60439; CHRISTIAN W. M ÜLLER, WILLIAM H. JAMES III and TIMOTHY S. ZWIER, Department of Chemistry, Purdue University, West Lafayette, IN 47907-2084. Crown ethers are well-studied examples of flexible macrocycles with a high binding selectivity for substrates, especially cations. We investigated the conformational preferences of the singly and doubly complexed water clusters of the crown ethers benzo-15-crown-5 (B15C) and its amino-derivative 4’-aminobenzo-15-crown-5 (ABC) cooled in a supersonic jet expansion. The fluorescence excitation, resonance enhanced two-photon ionization (R2PI), UV-UV holeburning (UVHB), fluorescence-dip infrared (FDIR), resonant ion-dip infrared (RIDIR) and novel IR-IR-UV holeburning spectra allowed for the identification of two )– conformers and one )– conformer. These conformers are characterized by an all-planar arrangement of the atoms directly bound to the benzene ring in which the crown ether macrocycle opens up to a symmetric structure and accomodates a doubly and triply H-bonded molecule in two distinct ways, respectively. Two )– conformers and one )– conformer were identified. One of the )– conformers contains a macrocycle configuration identical to that found in the monohydrated clusters with an H-bonding topology in which the molecules occupy both available sites simultaneously. The second )– conformer is assigned to an H-bond pattern in which the two molecules are concatenated to form an H-bonded bridge involving only three of the four available O–Hbonds (see figure). (1) V. A. Shubert and T. S. Zwier, J. Phys. Chem. A, 2007, 111, 13283. 129 TB11 10 min EFFECT OF SOLVENT ON PHOTO PHYSICAL CHARACTERISTICS OF SUBSTITUTED COUMARINS 11:42 RAJESH GIRI, DEPARTMENT OF FHYSICS AND ELECTRONICS, RAJDHANI COLLEGE, UNIVERSITY OF DELHI, RAJA GARDEN, NEW DELHI, INDIA; ,. Coumarin derivatives are hetrocyclic compounds with a ring oxygen on a carbonyl group and most of them occur as natural products with very efficient fluorescing ability. The photophysical characteristics of the compounds depend on nature and position of a substituent group in the parent molecule and also change due to a change in the surrounding media. Coumarins are widely studied due to their importance as laser dyes, non-linear optical chromophores and as excellent probe to studying solvation dynamics in the homogeneous solutions as well as in organized media . The photo physical characteristics of substituted coumarins viz. 4-methyl-5,7-diethoxy coumarin [1], 4-methyl-5-ethoxy-7-methoxy coumarin [2] and 4-methyl7,8-diethoxy coumarin [3] have been studied by recording their absorption and fluorescence spectra in various polar and non-polar organic solvents. The values of various spectral parameters like half band width, extinction coefficients, relative quantum yield), radiative life time and percentage polarization of all these coumarins in different solvents are calculated. Table [1-3]. The results obtained indicate a close relationship between the solvent polarity and fluorescence quantum yield. The variation is accounted for in terms of the positions of ($$ ) and ( $ ). Further the values of percentage polarisation of these molecules in various solvents of different polarity have been calculated and interpreted in terms of Perrin’s theory as well as dipole- dipole interaction. 130 TC. MINI-SYMPOSIUM: FIR/THz AIR/SPACE MISSIONS TUESDAY, JUNE 23, 2009 – 8:30 AM Room: 1000 McPHERSON LAB Chair: LI-HONG XU, University of New Brunswick, Saint John, NB, Canada TC01 Journal of Molecular Spectroscopy Review Lecture 30 min 8:30 HOW CAN SYNCHROTRON-BASED FTIR SPECTROSCOPY CONTRIBUTE TO ASTROPHYSICAL AND ATMOSPHERIC DATA NEEDS? A.R.W. McKELLAR, Steacie Institute for Molecular Sciences, National Research Council of Canada, Ottawa, ON K1A 0R6, Canada. Following the pioneering demonstration of gas-phase IR spectroscopy using synchrotron radiation (SR) at MAXLab and LURE, a number of new high resolution IR beamline facilities have recently become available, including those at the Canadian Light Source, the Australian Synchrotron, and Synchrotron SOLEIL. The high brightness of SR compared to conventional thermal sources gives potential signal gains of 2 to 3 orders of magnitude for this difficult region, though noise (e.g. from mechanical vibration) remains a problem. For astrophysical applications, comprehensive studies which involve measuring many thousands of transitions are needed for molecules ubiquitous in space (like methanol). Here the multiplex nature of FTIR spectroscopy is advantageous compared to the line-by-line nature of conventional microwave measurements. But is the accuracy sufficient? In recent Canadian Light Source spectra with line widths of 20 MHz and reasonable signal-to-noise ratio, line centers are routinely measured to better than 1 MHz. So it should be possible to approach the accuracy required by radio astronomers. Another astrophysical need is for improved data on unstable species (radicals and ions). Here the broad-band nature of FTIR helps with the search problem, and the high resolution possible with SR helps with sensitivity. But coherent (microwave or laser) sources may give better ultimate sensitivity. As well, synchrotron users face the challenge of creating unstable molecules (difficult enough in their own laboratory!) at the beamline where they may have only a few days of access. For terrestrial remote sensing, we wish to have complete and detailed spectral data for atmospheric molecules and potential pollutants. The availability of new synchrotron facilities will certainly help in this respect, particularly for the 50 - 500 range where coverage has been relatively limited. The required data are not limited to line positions. Detailed line shape information is also needed for a range of gas pressure, temperature, and mixture composition, in order to extract line broadening, shift, and mixing parameters. High spectral resolution and the multiplex nature of FTIR are advantageous, but, once more, the challenge is to establish the required sample conditions (precise, well-characterized pressure, temperature, path length, etc.) in the remote beamline laboratory. 131 TC02 15 min 9:05 THE HIGH RESOLUTION FAR-INFRARED SPECTRUM OF METHANE AT THE SOLEIL SYNCHROTRON V. BOUDON, Institut Carnot de Bourgogne, UMR 5209 CNRS-Universit é de Bourgogne, 9. Av. A. Savary, BP 47870, F-21078 Dijon Cedex, France; O. PIRALI, P. ROY, Ligne AILES – Synchrotron SOLEIL, L’Orme des Merisiers, F-91192 Gif-sur-Yvette, France; L. MANCERON, Laboratoire de Dynamique, Interactions et Réactivité, UMR 7075 - Universit Pierre et Marie Curie - CNRS, Case 49, 4 Place Jussieu, F-75252, Paris Cedex, France; J. VANDER AUWERA, Service de Chimie Quantique et Photophysique, Universit é Libre de Bruxelles, CP 160/09, 50 avenue F.D. Roosevelt - B-1050 Brussels, Belgium. As a tetrahedral molecule, methane has no permanent dipole moment. The spectrum of this molecule, however, displays faint absorption lines in the THz region, due to centrifugal distorsion effects. This is important for planetary applications since this region is used to measure methane concentration in some planetary atmospheres, in particular in the case of Titana . Up to now, all measurements were relying on some old low resolution spectra b . Even if these results have been reexamined recently c, it seemed highly desirable to obtain much more precise laboratory data. The high-intensity synchrotron radiation, combined with a 150 m optical path in a White cell and a Bruker IFS 125 HR FTIR spectrometer at the AILES beamline of SOLEIL, enabled us to record this very weak spectrum at high resolution for the first time. Spectra were recorded at 9.91, 20, 50 and 100 mbar pressure with a resolution of 0.0011, 0.002, 0.005 and 0.01 cm , respectively. The rotational clusters are fully resolved and the good signal-to-noise ratio should enable precise measurement of transition intensities, yielding an accurate determination of the dipole moment derivative. Such results should allow a better determination of CH concentration in planetary objects. a A. Coustenis, R. K. Achterberg, B. J. Conrath et al., Icarus 189, 35–62 (2007). Oldani, M. Andrist, A. Bauder and A. G. Robiette, J. Mol. Spectrosc., 110, 95–105 (1985). c E. H. Wishnow, G. S. Orton, I. Ozier and H. P. Gush, J. Quant. Spectrosc. Radiat. Transfer 103, 102–117 (2007). b M. TC03 15 min 9:22 FOURIER TRANSFORM MICROWAVE AND INFRARED SPECTROSCOPIC INVESTIGATION OF PROPIOLACTONE ZIQIU CHEN and JENNIFER VAN WIJNGAARDEN, Department of Chemistry, University of Manitoba, Winnipeg MB R3T 2N2 Canada. The pure rotational spectrum of the four-membered ester ring propiolactone (C H O ) has been measured in a supersonic jet between 7 and 22 GHz using Fourier transform microwave (FTMW) spectroscopy. For the normal isotopologue, a total of 19 a- and b-type transitions have been recorded. Fifteen transitions due to three different C isotopologues have also been observed. The microwave spectrum was analyzed to obtain an improved set of ground state rotational constants in comparison to earlier microwave experiments a. The new set of rotational parameters was used to predict the rovibrational band structure of the lowest frequency modes of propiolactone. A total of 12 vibrational band origins have been observed between 400 and 1500 cm using the far infrared beamline of the Canadian Light Source coupled to a Bruker IFS125HR spectrometer. The spectra were recorded with a resolution of 0.000969 cm and although the intensities of the bands vary, 9 bands are of sufficient quality for complete rovibrational assignment. The progress of the assignment of this rich spectrum will be discussed. a D. W. Boone, C O. Britt and J. E. Boggs J. Chem. Phys. 43 (1190), 1965. 132 TC04 15 min 9:39 THz SPECTROSCOPY OF H D F. MATSUSHIMA, T. YONEZU, Y. MORIWAKI, and K. TAKAGI, Department of Physics, University of Toyama, Gofuku, Toyama 930-8555, Japan; T. AMANO, Department of Chemistry, University of Waterloo, Waterloo, Canada N2L 3G1. The pure rotational transition frequencies of H D , , and , have been measured in the laboratory precisely by using a tunable far-infrared spectrometer. Among them, the line was recently detected in space toward Sgr B2 by Cernicharo et al. . Their identification was made based on a calculated line frequency estimated from the spectroscopic data of Amano and Hirao . It has been found that our measured frequency of this line, 2363242.82(69) MHz, is lower by about 20 MHz than the estimated value. All the available THz lines and known millimeter- and submillimeter-wave lines together with the combination differences derived from the infrared transitions are fitted to the Watson effective Hamiltonian. A set of improved molecular constants are obtained. ————————————— J.Cernicharo, E. Polehampton, and J.R. Goicoechea. Astrophys. J., 657, L21-L24 (2007). T. Amano and T. Hirao, J. Mol. Spectrosc., 233, 7-14 (2005). TC05 15 min 9:56 LABORATORY STUDIES OF THE FORMATION OF INTERSTELLAR DUST FROM MOLECULAR PRECURSORS CESAR S. CONTRERAS and FARID SALAMA, Space Science Division, NASA-Ames Research Center, Moffett Field, CA, USA. The study of the formation and the destruction processes of cosmic dust is essential to understand and to quantify the budget of extraterrestrial organic molecules. Interstellar dust presents a continuous size distribution from large molecules, radicals and ions to nanometer-sized particles to micron-sized grains. The lower end of the carbonaceous dust size distribution is thought to be responsible for the ubiquitous spectral features that are seen in emission in the IR (UIBs) and in absorption in the visible (DIBs). The higher end of the dust-size distribution is thought to be responsible for the continuum emission plateau that is seen in the IR and for the strong absorption seen in the interstellar UV extinction curve. All these spectral signatures are characteristic of cosmic organic materials that are ubiquitous and present in various forms from gas-phase molecules to solid-state grains and all are expected to exhibit FIR spectral signatures. Space observations from the UV (HST) to the IR (ISO, Spitzer) help place size constraints on the molecular component of carbonaceous IS dust and its contribution to the IS features in the UV and in the IR. Studies of large molecular and nano-sized IS dust analogs formed from PAH precursors have been performed in our laboratory under conditions that simulate interstellar and circumstellar environments. The species (molecules, molecular fragments, ions, nanoparticles, etc...) formed in the pulsed discharge nozzle (PDN) plasma source are detected and characterized with a high-sensitivity cavity ringdown spectrometer (CRDS) coupled to a Reflectron time-of-flight mass spectrometer (ReTOF-MS). We will present new experimental results that indicate that nanoparticles are generated in the plasma. From these unique measurements, we derive information on the nature, the size and the structure of interstellar dust particles, the growth and the destruction processes of IS dust and the resulting budget of extraterrestrial organic molecules. Acknowledgements: This work is supported by NASA SMD (Planetary Science and APRA R&A Programs). C.S. Contreras acknowledges the support of the NASA Postdoctoral Program (NPP). Intermission 133 TC06 THE SUBMILLIMETER SPECTRUM OF CH CH CN IN ITS GROUND VIBRATIONAL STATEa 15 min 10:30 CAROLYN S. BRAUER, JOHN C. PEARSON, BRIAN J. DROUIN, SHANSHAN YU, JET PROPULSION LABORATORY, CALIFORNIA INSTITUTE OF TECHNOLOGY, 4800 OAK GROVE DR., PASADENA, CA 91109. Propionitrile (CH CH CN) is routinely observed with large column densities and at surprisingly high temperatures in hot core sources. The development of new, more sensitive observatories such as Herschel, ALMA and SOFIA have made it important to extend the laboratory data for propionitrile to coincide with the capabilities of the new instruments. In the present work, the laboratory measurements of the rotational spectrum of propionitrile have been extended to 1.6 THz. A global analysis of 4606 ground state transitions, which includes 2159 newly assigned transitions, has been fit to within experimental error to & , ' , using both Watson reduced and Watson reduced Hamiltonians. The newly assigned transitions are primarily *type, high ' and very high & asymmetry split -branch transitions. The derived constants show a decided advantage of the Watson reduction in the analysis of this near-prolate (< %) asymmetric top. The spectrum and molecular constants will be presented. a Research described in this paper was performed at the Jet Propulsion Laboratory, California Institute of Technology, under contracts and cooperative agreements with the National Aeronautics and Space Administration. TC07 15 min 10:47 ANALYSIS OF THE LOWEST IN-PLANE BEND AND FIRST EXCITED TORSIONAL STATE OF CH CH CNa CAROLYN S. BRAUER, JOHN C. PEARSON, BRIAN J. DROUIN, SHANSHAN YU, JET PROPULSION LABORATORY, CALIFORNIA INSTITUTE OF TECHNOLOGY, 4800 OAK GROVE DR., PASADENA, CA 91109. Propionitrile (CH CH CN) is observed with large column densities in a number of high-mass star-forming cores, where core temperatures exceed 200 K. It is a near-prolate (< %) asymmetric top with appreciable dipole moment components on both the and *axes ( % D, % D).a This, combined with the presence of four fundamental modes as well as four overtones and combination bands all occurring below 600 cm , results in a very rich spectrum. It is known to be a major contributor to spectral line confusion in ground-based observations and is expected to complicate observations by Herschel, SOFIA and ALMA, making it imperative to fully characterize the entire spectrum. The lowest in-plane bend, , is 206.9(0.5) cm ,b and the first excited torsional state, , which is just 186 GHz above, have been detected in hot cores with antenna temperatures of a few Kelvin. c The close proximity of and , as well as their low-lying nature, offers a unique opportunity to study the vibration-torsion-rotation coupling problem in the case of two nearly degenerate vibrational states. As expected from symmetry and their and nature, these states exhibit strong and *symmetry Coriolis interactions, as well as interactions resulting from different sets of Eckhart-Sayvetz conditions being required in and . In the present work, the and states of propionitrile have been analyzed to high frequency and angular momentum quantum number. The spectrum, molecular constants,and insights into the vibration-torsion-rotation problem will be discussed. a Research described in this paper was performed at the Jet Propulsion Laboratory, California Institute of Technology, under contracts and cooperative agreements with the National Aeronautics and Space Administration. a H. M. Heise, H. Lutz & H. Dreizler,Z.Nat.,29a,1345 (1974). b H. M. Heise, F. Winther & H. Lutz,J. Mol. Spectrosc.,90,531 (1981). c D. M. Mehringer, J. C. Pearson, J. Keene & T. G. Phillips,Ap.J.,608,306 (2004). 134 TC08 THE LABORATORY ROTATIONAL SPECTRUM OF SEARCH IN SAGITTARIUS B2(N) 15 min 11:04 -PROPYL CYANIDE AND AN ASTRONOMICAL HOLGER S. P. MÜLLER, I. Physikalisches Institut, Universit ät zu Köln, 50937 K öln; and Max-PlanckInstitut für Radioastronomie, 53121 Bonn, Germany; A. COUTENS, A. WALTERS, CESR, Universit é de Toulouse (UPS), and CNRS, 31028 Toulouse, France; J.-U. GRABOW, Institut f ür Physikalische Chemie und Elektrochemie, Lehrgebiet A, Universit ät Hannover, 30167 Hannover, Germany; A. BELLOCHE, K. M. MENTEN, Max-Planck-Institut f ür Radioastronomie, 53121 Bonn, Germany; S. SCHLEMMER, I. Physikalisches Institut, Universit ät zu Köln, 50937 K öln, Germany. We have carried out a molecular line survey of Sagittarius B2(N) in the 3 mm region with selected recordings at 2 and 1.3 mm to probe the chemical complexity in massive star-forming regions. Noteworthy results include the detection of aminoacetonitrile, a a possible precursor of the aminoacid glycine, the detection of C isotopologs of vinyl cyanide, b and the detection of ethyl formate as well as =-propyl cyanide. c The heavy atoms in the latter molecule form a chain. An isomer with a branched structure, 9-propyl cyanide, also exists, but its rotational spectrum has only been recorded in few transitions up to 40 GHz. de Therefore, laboratory measurements were extended. The molecule is rather asymmetric (< %) with a strong -dipole moment component of 4.05 (2) D and a still sizable -component of 1.4 (2) D. Measurements in Köln were carried out in selected regions between 40 and 600 GHz. Since the -type transitions appeared to be weaker than predicted additional Stark (and also zero-field) measurements have been carried out in Hannover between 6 and 20 GHz. We will present results of these laboratory spectroscopic investigations as well as the outcome of a search for the molecule in our Sgr B2(N) line survey. a A. Belloche, K. M. Menten, C. Comito, H. S. P. Müller, P. Schilke, J. Ott, S. Thorwirth, C. Hieret, Astron. Astrophys. 482 (2008) 179; Erratum 492 (2008) 796. b H. S. P. Müller, A. Belloche, K. M. Menten, C. Comito, P. Schilke, J. Mol. Spectrosc. 251 (2008) 319. c A. Belloche, R. T. Garrod, H. S. P. Müller, K. M. Menten, C. Comito, P. Schilke, Astron. Astrophys. (2009), accepted. d G. E. Herberich, Z. Naturforsch. 22a (1967) 543. e J. R. Durig, Y. S. Li, J. Mol. Struct. 21 (1974) 289. TC09 ROTATIONAL SPECTROSCOPY OF ETHYLAMINE INTO THE THz 15 min 11:21 ZBIGNIEW KISIEL, ADAM KRASNICKI, Institute of Physics, Polish Academy of Sciences, Al. Lotnik ów 32/46, 02-668 Warszawa, Poland; IVAN R. MEDVEDEV, CHRISTOPHER NEESE, SARAH FORTMAN, MANFRED WINNEWISSER, FRANK C. DE LUCIA, Department of Physics, The Ohio State University, Columbus, OH 43210; HOLGER S. P. M ÜLLER, I. Physikalisches Institut, Universit ät zu Köln, Zülpicher Str. 77, 50937 K öln, Germany. Ethylamine is one of the molecules that exhibits a challenging combination of two low frequency motions: inversion and internal rotation. The separation between these modes is fortunately appreciably greater than in the lighter methylamine, and the cm-wave rotational spectra of anti-ethylamine a and ./#0-ethylamine b have been assigned some time ago. Recent astrophysical interest prompted laboratory investigation of 9-ethylamine up to 270 GHz and an associated astronomical search for this species in Sgr B2(N). c We report extensive new coverage of the rotational spectrum of ethylamine obtained in the form of three broadband segments, each recorded by using a different instrumental technique. The spectrum in the 115-376 GHz region was obtained with the FASSST spectrometer, d at 555-650 GHz by using cascaded harmonic multiplication from a cm-wave synthesizer, and at 867-1081 GHz by also using FASSST, but with frequency tripled output from a 300 GHz-region BWO oscillator. The spectrum is at an advanced stage of analysis, carried out by means of the graphical assignment AABS package, e and results obtained for both 9- and ./#0-ethylamine are presented. a E.Fischer, E.Botskor, J. Mol. Spectrosc., 91, 116-127 (1982). E.Botskor, J. Mol. Spectrosc., 104, 226-247 (1984). c A.J.Apponi, et al., Astrophys. J., 673, 1240-1248 (2008). d I.Medvedev et al., J. Mol. Spectrosc., 228, 314-328 (2004). e Z.Kisiel et al., J. Mol. Spectrosc., 233, 231-243 (2005). b E,Fischer, 135 TC10 THE SPECTRUM OF METHYL FORMATE IN THE THZ REGION 15 min 11:38 M. TUDORIE, T. R. HUETa , L. MARGULES, M. GOUBET, Laboratoire de Physique des Lasers, Atomes et Molécules (PhLAM) UMR 8523 CNRS, B ât. P5, Université des Sciences et Technologies de Lille 1, 59655 Villeneuve d’Ascq Cedex, France; O. PIRALI, P. ROY, Ligne AILES, synchrotron SOLEIL, LOrme des Merisiers, Saint Aubin, BP 48, 91192 Gif-sur-Yvette, France; V. V. ILYUSHIN, Institute of Radio Astronomy of NASU, Chervonopraporna 4, 61002 Kharkov, Ukraine; I. KLEINER, LISA, CNRS/Universit és Paris 12 et 7, 61 Avenue du Général de Gaulle, 94010 Créteil, France. The THz spectrum of methyl formate-HCOOCH is currently investigated. At first a multi-pass cell having an optical path of 150 m coupled to an internal source of the Fourier Transform spectrometer of the AILES beamline, synchrotron SOLEIL (France), was used to obtain the methyl formate THz spectrum. Preliminary assignments of the pure rotation spectrum up to 80 cm , and of the very weak torsion band v = 1-0 around 130 cm are carried out. The assignments are based on the rotation-torsion energy levels calculated using the RAM approach b. The particular interest in v = 1 torsion-rotation band lies in the direct experimental determination of the barrier height V , which up to now was determined from pure rotational transitions only, and consequently in the contribution to the improvement of the global study of the rotational levels in the lowest torsional states of methyl formate. Secondly further measurements using the synchrotron radiation are planned. The latest results will be presented. a This work is supported by the ANR-08-BLAN-0054 contract Kryvda, Alekseev, J. Mol. Spectrosc. (2009), doi: 10.1016/j.jms.2009.01.016 b Ilyushin, TC11 15 min PRELIMINARY WORK TO ALMA: SUBMILLIMETER WAVE SPECTROSCOPY OF METHYL FORMATEa O 11:55 AND D SPECIES OF L. MARGULÈS, R. MOTIYENKO, T. R. HUET, Laboratoire PhLAM, CNRS UMR 8523, Universit é de Lille 1, 59655 Villeneuve d’Ascq Cedex, France.; H. MØLLENDAL, Centre for Theoretical and Computational Chemistry (CTCC), University of Oslo, P. O. Box 1033, Blindern, NO-0315 Oslo, Norway; J.C. GUILLEMIN, Sciences Chimiques de Rennes-Ecole Nationale Sup érieure de Chimie de Rennes-CNRS, 35700 Rennes, France; K. DEMYK, Centre d’Etude Spatiale des Rayonnements, Universit é de Toulouse 3, 31028 Toulouse cedex 4, France; M. CARVAJAL, Departamento de F ı̀sica Aplicada, Universidad de Huelva, Spain; I. KLEINER, and L. H. COUDERT, LISA, CNRS UMR 7583, Universit é Paris 12, 94010 Créteil Cedex France. New radiotelescopes, working in the submillimeter range, will be operating in the next few years: ALMA, Herschel, and SOFIA. A large amount of laboratory work is required in order to account for the increased resolution and accuracy needed to analyze the numerous data which will be obtained with these new instruments. There is a strong interest of the astrophysical community in isotopic species for two main reasons: (i) Their detection provides us with key information about interstellar chemical modeling, especially for complex organic molecules, like methyl formate, as their formation mechanisms is not well understood yet. (ii) They are responsible for a large fraction of U-lines and their assignments are necessary to allow the detection of new species. In this context we continue a systematic study of the isotopic species of methyl formate (HCOOCH ) initiated with H COOCH .b Our next investigation of HCOO CH allowed us the detection of 500 lines in Orion. c The treatment of the data concerning methyl formate is not obvious due to the internal rotation of the methyl group. This treatment is different in case of a symmetric (CH ) or an asymmetric (CHD ) rotor part. We will report here on recent results obtained for DCOOCH , HCOOCHD , HC OOCH , and HCO OCH . a This work is supported by ANR-08-BLAN-0054 and ANR-08-BLAN-0225 Møllendal, Alekseev, et al. J. Mol. Struct. 795 (2006) 4 c Carvajal, Margules, Tercero, et al. Astron. Astrophys. (2009) in press b Willaert, 136 TD. MINI-SYMPOSIUM: CAVITY ENHANCED SPECTROSCOPY TUESDAY, JUNE 23, 2009 – 8:30 AM Room: 1015 McPHERSON LAB Chair: KEVIN LEHMANN, University of Virginia, Charlottesville, Virginia TD01 INVITED TALK 30 min 8:30 ANALYSIS OF REACTION MECHANISMS IN FLAMES USING COMBINED CRD- AND LIF-SPECTROSCOPY ANDREAS BROCKHINKE, PATRICK NAU, MARKUS KÖHLER and KATHARINA KOHSEHÖINGHAUS, Physikalische Chemie I, Universit ät Bielefeld, Universitätsstraße 25, D-33615 Bielefeld, Germany. Laser-based non-intrusive diagnostic techniques are firmly established as the most versatile tools to study high-temperature gas-phase reactions in general and combustion processes in particular. While fossil fuels remain the most important primary energy carriers, alternative fuels gain in importance. Usually, these fuels contain significant amounts of oxygen, nitrogen and sulphur, leading to different reaction pathways than in the established combustion of hydrocarbons. In order to minimize the formation of pollutants and hazardous compounds (soot, CO, NO ) and increase efficiency, a deeper understanding of these reaction processes is essential. Optical measurements, in particular Cavity Ring-Down Spectroscopy (CRDS) and Laser Induced Fluorescence spectroscopy (LIF), have proven to be well suited for quantitative radical measurements in flames (e.g. OH, CH , C , HCO). Both techniques provide high sensitivity and selectivity. Our revised experimental setup is designed for quasi-simultaneous measurements, combining the positive features of both complementary techniques. In addition, invasive methods like mass-spectrometry are performed in order to gain a complete understanding of the flame species. In this contribution, we will focus on the quantitative determination of important minor species such as CN, NH , CH and formaldehyde in low-pressure flat flames. In addition to investigations of flames with hydrocarbon fuels, we present the first optical measurements in morpholine- and ethylamine-flames. Aim of these measurements is to study the conversion of fuel nitrogen to NO . Experimental results will be compared with numerical CHEMKIN-II simulations. TD02 MID-IR ETHENE DETECTION USING A QUASI-PHASE MATCHED LiNbO WAVEGUIDE 15 min 9:05 ROBERTO GRILLI, School of Chemistry, University of Bristol, Bristol BS8 1TS, U.K.; LUCA CIAFFONI, GRANT A. D. RITCHIE, Department of Chemistry, Physical and Theoretical Chemistry Laboratory, University of Oxford, South Parks Road, Oxford OX1 3QZ, U.K.; and ANDREW J. ORR-EWING, School of Chemistry, University of Bristol, Bristol BS8 1TS, U.K.. A periodically poled LiNbO waveguide has been used to produce up to 200 W of mid-infrared light around 3081 cm with a wide tunability range of 833 cm . Two commercial near-infrared diode lasers at 1.064 m (pump) and 1.583 m (signal) are mixed in a nonlinear optical crystal to achieve difference frequency generation. The 48 mm long direct-bonded quasi-phase matched periodically poled LiNbO waveguide shows a conversion efficiency of 12.3 %/W. The radiation sits in an important window of the mid-infrared spectral region, where a large number of fundamental vibrations of several hydrocarbons occur. Applications in trace gas detection have been demonstrated for ethene, using multi-pass absorption coupled with wavelength modulation spectroscopy to reach a minimum absorption coefficient of 3 10 cm Hz . The relatively high power of the mid-infrared idler radiation obtained shows great potential for higher sensitive techniques such as cavity enhanced absorption spectroscopy and cavity ring-down spectroscopy, and preliminary results will be presented. a a L. Ciaffoni, R. Grilli, G. Hancock, A.J. Orr-Ewing, R. Peverall and G. A. D. Ritchie Appl. Phys. B 94, 517-525, 2009. 137 TD03 15 min 9:22 MEASUREMENTS OF EXTINCTION BY AEROSOL PARTICLES USING CAVITY RING-DOWN SPECTROSCOPY AND OPTICAL FEEDBACK CAVITY RING-DOWN SPECTROSCOPY DANIEL MELLON, JIN KIM and ANDREW J. ORR-EWING, School of Chemistry, University of Bristol, Bristol BS8 1TS, U.K.. Cavity ring-down spectroscopy and optical feedback cavity ring-down spectroscopy using continuous-wave distributedfeedback diode lasers around 1.6 m and 400 nm have been used to measure the extinction of light by samples of monodisperse spherical aerosol particles 5 1 m in diameter. A statistical model is proposed to describe the linear relationship between the extinction coefficient () and its variance Var(). Application of this model to experimental measurements of Var() for a range of () values typically below 2 10 cm allows extinction cross sections for the aerosol particles to be obtained without need for knowledge of the particle number density. Samples of polystyrene spheres with diameters of 400 nm, 500 nm, 600 nm, 700 nm and 900 nm were used to test the model, by comparing extinction cross sections determined from the experiment with the predictions of Mie theory calculations. The fitting method used to extract decay constants, aggregation of particles and their cloud-like motion can all provide extra contributions to Var() and are understood with the aid of computer simulations. a a T.J.A. Butler, D. Mellon, J. Kim, J. Litman and A.J. Orr-Ewing J. Chem. Phys. A in press (2009) TD04 15 min 9:39 TIME-DEPENDENT EMISSION OF MOLECULAR IODINE FROM BROWN SEAWEED: AN APPLICATION OF INCOHERENT BROADBAND CAVITY-ENHANCED ABSORPTION SPECTROSCOPY SOPHIE DIXNEUFa , ANDY A. RUTH, Laser Spectroscopy Group, Physics Department, University College Cork, Ireland; STEWART VAUGHAN, School of Chemistry, University of Leeds, United Kingdom; RAVI M. VARMA, Laser Spectroscopy Group, Physics Department, University College Cork, Cork, Ireland; and JOHANNES ORPHAL, Laboratoire Inter-universitaire des Syst èmes Atmosphériques, Université Paris XII, Créteil, France. A large variety of gases enters the atmosphere from seawater and is the driving force of local and global atmospheric processes. Since knowing the composition of gases evolving from the sea and the total fluxes involved is a precondition for the development of quantitative atmospheric models, sea-to-air exchange mechanisms are subject of intense investigation. The release of volatile organic iodine compounds and of molecular iodine (I ) into the marine boundary layer is recognized to be of fundamental importance for (subsequent) ozone depletion events and marine aerosol formation, which in turn affects global radiative forcing. Although biogenic emission (iodovolatilization) of I by phytoplankton in open waters and via macrophytic algae in coastal areas, has been suggested to be one of the most important processes leading to the observed iodine concentrations in the marine troposphere, the dominant sources of molecular iodine and in particular the mechanisms of I release are still being debated. We used incoherent broadband cavity-enhanced absorption spectroscopy (IBBCEAS) for the first quasi in situ detection of molecular iodine after emission from the brown macroalgae, Laminaria digitata, under naturally occurring stress. Since IBBCEAS combines a high spatial and temporal resolution with high molecule-specific detection sensitivity it is ideally suited to study point sources of atmospheric trace constituents. In this context IBBCEAS complements long-path DOAS setups in the search for trace gas emission sources. In this presentation we will show that the release of I occurs in short, regularly occurring, strong bursts. The new data suggest that the control of I release by the plant may be based on a nonlinear reaction scheme involving the release of H O on the plants surface, leading to quasi-oscillatory emission behaviour. Preliminary measurement of flux estimates of I release per kg of dry weight of the plant will be discussed. a s.dixneuf@ucc.ie 138 TD05 MEDICAL DIAGNOSTIC BREATH ANALYSIS BY CAVITY RING DOWN SPECTROSCOPY 15 min 9:56 JOSEPH S. GUSS, MARKUS METSÄLÄ and LAURI HALONEN, Laboratory of Physical Chemistry, Department of Chemistry, P.O. Box 55, 00014 University of Helsinki, Finland. Certain medical conditions give rise to the presence of chemicals in the bloodstream. These chemicals — known as biomarkers — may also be present in low concentrations in human breath. Cavity ring down spectroscopy possesses the requisite selectivity and sensitivity to detect such biomarkers in the congested spectrum of a breath sample. The ulcercausing bacterium, Helicobacter pylori, is a prolific producer of the enzyme urease, which catalyses the breakdown of urea ((NH ) CO) in the stomach as follows: (NH ) CO + H O CO + 2NH Currently, breath tests seeking altered carbon-isotope ratios in exhaled CO after the ingestion of C- or C-labeled urea are used to diagnose H. pylori infection. a We present recent results from an ongoing collaboration with Tampere Area University Hospital. The study involves 100 patients (both infected and uninfected) and concerns the possible correlation between the bacterial infection and breath ammonia. a D. Y. Graham, P. D. Klein, D. J. Evans, Jr, D. G. Evans, L. C. Alpert, A. R. Opekun, T. W. Boutton, Lancet 1(8543), 1174-7 March 1987. Intermission TD06 10 min THE FANTASIO SET-UP (I): DESCRIPTION AND EXTENSION TOWARDS FEMTO-FANTASIO 10:30 K. DIDRICHE, C. LAUZIN, X. DE GHELLINCK, P. MACKO, A. RIZOPOULOS, P. VAN POUCKE, M. HERMAN, Service de Chimie quantique et Photophysique CP160/09, Facult é des Sciences, Université Libre de Bruxelles (U.L.B.), Av. Roosevelt, 50, B-1050, Bruxelles, Belgium; S. KASSI, Laboratoire de Spectrométrie Physique, Laboratoire de Spectromtrie Physique, Universit é Joseph Fourier de Grenoble, B.P. 87, 38402 Saint-Martin-d’Heres Cedex, France. We have built the FANTASIO set-up (for ”Fourier trANsform, Tunable diode and quadrupole mAss spectrometers interfaced to a Supersonic expansIOn”) to investigate jet-cooled molecules and dimers a . The set-up will be described. New developments are on the way, to be illustrated by preliminary results. These include the doubling of the vacuum pumping system efficiency. They will also allow for a Femto OPO system to be used as a broadband, cavity enhanced absorption source to be interfaced to the supersonic expansion and to the high resolution FTIR instrument of FANTASIO. a M. Herman, K. Didriche, D. Hurtmans, B. Kizil, P. Macko, A. Rizopoulos and P. Van Poucke, Mol. Phys., 105, 843 (2007). 139 TD07 15 min 10:42 THE FANTASIO SET-UP (II): HIGH RESOLUTION OVERTONE SPECTROSCOPY OF ACETYLENE CONTAINING VAN DER WAALS DIMERS C. LAUZIN, J. DEMAISON, K. DIDRICHE, P. MACKO, J. LIEVIN, M. HERMAN, Service de Chimie quantique et Photophysique CP160/09, Facult é des Sciences, Université Libre de Bruxelles (U.L.B.), Av. Roosevelt, 50, B-1050, Bruxelles, Belgium; A. PERRIN, Laboratoire Interuniversitaire des Syst èmes Atmosphériques (LISA) CNRS-UMR 7583 Université Paris Est et Paris 7, Faculté des Sciences et Technologie, 61, avenue du Général de Gaulle 94010 Créteil Cédex, France; W.J. LAFFERTY, Optical Technology Division, National Institute for Standards and Technology, Gaithersburg, MD 20899-8441, USA. We have used the CW-CRDS facility in the FANTASIO set-up described in the previous presentation to investigate acetylene-containing dimers formed in a supersonic expansion, in the 1.5 microns range. Ab initio calculations were also performed in some cases. The acetylene partners so far include argon a, carbon dioxide b and nitrous oxide c . The results will be illustrated. a C. Lauzin, K. Didriche, P. Macko, J. Demaison, J. Liévin, and M. Herman, J. Phys. Chem. A, in press (2009). Lauzin, K. Didriche, J. Liévin, M. Herman, and A. Perrin, J. Chem. Phys, submitted (2009). c K. Didriche, C. Lauzin, P. Macko, M. Herman, and W.J. Lafferty, Chem. Phys. Letters, doi:10.1016/j.cplett.2008.12.037 (2008). b C. TD08 FIBER-LASER-BASED NICE-OHMS FOR TRACE GAS DETECTION 15 min 10:59 A. FOLTYNOWICZ, W. MA, and O. AXNER, Department of Physics, Ume å University, SE-907 87 Ume å, Sweden. Noise-immune cavity-enhanced optical heterodyne molecular spectroscopy (NICE-OHMS) is an absorption technique that combines frequency modulation (FM) for reduction of noise with cavity enhancement for increased interaction length with the sample to provide ultra-high detection sensitivity. ab The carrier of the FM triplet is locked to a mode of an external cavity and the FM modulation frequency is matched to the cavity free spectral range (FSR), thus the sidebands are transmitted through adjacent cavity modes. As a result any residual frequency noise of the laser carrier leads to the same amplitude attenuation and phase shift of the sidebands, wherefore FM spectroscopy can be performed inside the cavity without introduction of additional noise, yet benefiting from the cavity enhancement of length and laser power. The main technical difficulty of NICE-OHMS is the locking of the laser frequency to a cavity mode. We will present a recently developed compact NICE-OHMS spectrometer based on an erbium-doped fiber laser, whose narrow linewidth (1 kHz/120 s) simplifies the locking procedure significantly. c The use of integrated-optics devices, such as a fiber-coupled electro-optic modulator, further reduces the complexity of the system. The fiber-laser-based NICE-OHMS spectrometer is capable of detecting both Doppler-broadened and sub-Doppler signals with a sensitivity in the 10 cm range, using a cavity with a finesse of 4800. de The two detection modes will be compared and experimental results from C H and CO at 1531 nm under low pressure conditions will be presented. The dependence of signal strengths and shapes on analyte concentration and other experimental parameters (such as intracavity power and pressure, cavity FSR and FM detection phase), as well as the optimum detection conditions will be discussed. a J. Ye, L. S. Ma, and J. L. Hall, J. Opt. Soc. Am. B 15, 6 (1998). Foltynowicz, F. M. Schmidt, W. Ma, and O. Axner, Appl. Phys. B 92, 313 (2008). c F. M. Schmidt, A. Foltynowicz, W. Ma, and O. Axner, J. Opt. Soc. Am. B 24, 1392 (2007). d F. M. Schmidt, A. Foltynowicz, W. Ma, T. Lock, and O. Axner, Opt. Express 15, 10822 (2007). e A. Foltynowicz, W. Ma, and O. Axner, Opt. Express 16, 14689 (2008). b A. 140 TD09 15 min 11:16 DETERMINATION OF ABSORPTION CROSS SECTIONS OF SURFACE-ADSORBED NITRIC ACID IN THE 290330 NM REGION BY BREWSTER ANGLE CAVITY RING-DOWN SPECTROSCOPY C. ZHU, B. XIANG, R. COLE, AND L. ZHU, Wadsworth Center, New York State Department of Health, and Department of Environmental Health Sciences, State University of New York, Albany, NY 12201. We have measured absorption cross sections of surface-adsorbed nitric acid in the 290-330 nm region with Brewster angle cavity ring-down spectroscopy. The 295 K absorption cross sections for nitric acid adsorbed on fused silica surfaces are at least two orders of magnitude larger than those in the gas phase in the wavelength region studied. Our work extends the application of Brewster angle cavity ring-down spectroscopy to the UV region, and further demonstrates the capabilities of this technique. Our results can account for the field-observed large differences between nitric acid photolysis rates on the surface and that of the gas phase. TD10 CAVITY RING DOWN ABSORPTION OF HD AT 90K 15 min 11:33 CARLOS E. MANZANARES and YASNAHIR PEREZ-DELGADO, Department of Chemistry and Biochemistry, Baylor University, Waco, Texas, 76798. Cavity ring down is an ideal technique to detect weak molecular absorptions because of the long optical path lengths (order of km) that can be achieved. Coupling the method to a custom fitted cryostat allows gas phase molecules to be studied at cryogenic temperatures in a thermally isolated vacuum chamber. A novel design is described to construct the complete instrument. With optical cavities of length between 10 cm (>) 43 cm, optical path lengths between 200 m and 8 km have been achieved. High vibrational overtones H-D are measured at 90 K. The experimental set up can be used to study kinetics and spectroscopy of atmospheric molecules, planetary atmospheres, and molecular complexes in the gas phase at temperatures below 298 K using liquid He or liquid as cryogens. 141 TE. RADICALS AND IONS TUESDAY, JUNE 23, 2009 – 8:30 AM Room: 2015 McPHERSON LAB Chair: CARL GOTTLIEB, Harvard Smithsonian Center for Astrophyics, Cambridge, MA TE01 15 min 8:30 THE SPECTRA OF SOLID XENON LUMINESCENCE EXCITED BY THE BULK ELECTRIC DISCHARGE. E. B. GORDON, Institute of Problems of Chemical Physics RAS, Chernogolovka, 142432 Russia; V. D. SIZOV AND V. I. MATYUSHENKO, Institute of Energy Problems of Chemical Physics RAS, Chernogolovka, 142432 Russia. The spectra of solid xenon bulk luminescence initiated by electric discharge were observed for the first time a . Along with powerful excitonic resonance emission in VUV the spectrum contained numerous strong lines in UV and visible originated from the transitions between excited states of the matrix. The main peculiarity in these UV and visible spectra was the complete absence of lines belonged to neutral excited species - atom-like Xe and molecular-like Xe excitons, although these lines are usually very strong in xenon gas discharges. The lines of molecular ions Xe were absent as well. The most lines were identified as atomic ion Xe transitions which are unobservable in relatively dense gas due to their fast conversion into Xe . The Xe lines positions were slightly (0.1 - 0.3 nm) shifted in relation to their positions in the gas phase and their shapes in many cases were rather distorted. The mechanism of solid xenon excitation and ionization by the fast electrons drifted in electric field has been proposed on the basis of experimental data analysis. a E.B.Gordon, V.I. Matyushenko, V.D.Sizov, and V.B.Fokin, Optics and Spectroscopy 34, 786 (2009). TE02 15 min 8:47 HIGH-RESOLUTION NEAR-INFRARED SPECTROSCOPY OF DEUTERATED CH HAIMING WANG, MARIA KLESHCHEVA, CHRISTOPHER P. MORONG, and TAKESHI OKA, Department of Chemistry, Department of Astronomy Astrophysics, and the Enrico Fermi Institute, University of Chicago, Chicago, IL 60637. Laboratory spectroscopy of deuterated molecular ions is essential in understanding deuterium ion chemistry-a significant area in astrochemistry since the discovery of many extraordinarily abundant deuterated species in prestellar cores and protostars in recent years. Aiming at providing approximate rotational constants for millimeter wave spectroscopists to identify the corresponding species in space, we are measuring the near-infrared spectrum of deuterated CH . CH is the intermediate between the abundant CH and yet to be observed but very important CH in interstellar chemistry. Its a b abundance is expected in diffuse clouds although our search for interstellar CH based on our infrared and near-infrared laboratory spectra has not been successful yet. CH and its deuterated species are also of special interest for theoretical studies because of their unique intramolecular dynamics, i.e., the Renner-Teller interaction and quasi-linearity. Using He-dominated liquid-N cooled plasmas (10 Torr) containing a small amount (0.1 Torr) of CD , we have mea to 12,500 cm with our Ti:sapphire laser spectrometer sured the spectra of CD in the near-infrared from 11,000 cm that combines velocity modulation and phase modulation with heterodyne detection for near shot-noise-limited sensitivity. , and bands of CD The have been identified and analyzed so far c . Currently a scan for CHD using CH D gas is underway. The spectrum will be discussed in comparison with the theoretical predictions by Bunker and colleagues d . a M. Rösslein, C. M. Gabrys, M.-F. Jagod, and T. Oka, J. Mol. Spectrosc. 153, 738 (1992). L. Gottfried and T. Oka, J. Chem. Phys. 121, 11527 (2004). c H.-M. Wang, C. P. Morong, and T. Oka, 62 , 63 OSU International Symposium on Molecular Spectroscopy, MJ02 (2007) and WG04 (2008). d P. R. Bunker, private communications. b J. 142 TE03 15 min 9:04 CHEMICAL PROBING SPECTROSCOPY OF H IN A CRYOGENIC RADIOFREQUENCY TRAP HOLGER KRECKELa , DENNIS BING, SASCHA REINHARDT, ANNEMIEKE PETRIGNANI, MAX BERG, and ANDREAS WOLF, Max-Planck-Institut f ür Kernpysik, Saupfercheckweg 1, 69117 Heidelberg, Germany. The H molecular ion is a key species for the chemistry of the interstellar medium. Being the simplest polyatomic ion it also serves as a benchmark system for quantum chemistry calculations. Due to the absence of a permanent dipole moment and since no stable electronically excited states are known, spectroscopy is restricted to vibrational transitions in the infrared. To date more than 800 transitions covering states up to 13 600 cm above the ground state have been observed. Nevertheless, for a better understanding of H dissociation and dynamics, it is necessary to extend that range considerably towards the dissociation limit of 35 000 cm . We have developed a chemical probing technique that is able b to probe high-lying H states with unprecedented sensitivity . The H ions are buffer-gas cooled in a radiofreqeuncy ion trap at 55 K. Argon is let in as a probe gas and laser transitions between 11 330 and 13 300 cm trigger the formation of ArH ions which are detected by a quadrupole mass spectrometer. Here, we report the detection of the weakest H transitions observed to date and discuss the possible extension of the scheme into visible wavelengths and beyond. a present b H. address: Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA Kreckel, D. Bing, S. Reinhardt, A. Petrignani, Max Berg, and A. Wolf, J. Chem. Phys. 129, 164312 (2008) TE04 15 min 9:21 A CONTINUOUS SUPERSONIC EXPANSION DISCHARGE NOZZLE FOR ROTATIONALLY COLD IONS CARRIE A. KAUFFMAN, KYLE N. CRABTREE, Department of Chemistry, University of Illinois, Urbana, Illinois 61801; BENJAMIN J. MCCALL, Departments of Chemistry and Astronomy, University of Illinois, Urbana, Illinois 61801. Molecular ions play an important role in chemistry and astronomy. In particular, molecular ions are key reaction intermediates, and in the interstellar medium, where temperatures and densities are low, they dominate the chemistry. Studying these ions spectroscopically in the laboratory poses a difficult challenge due to their reactivity. In our effort to study molecular ions, our research group is building SCRIBES (Sensitive Cooled Resolved Ion BEam Spectroscopy), which combines a cold ion source, mass spectrometry, and cavity ring-down spectroscopy. With this apparatus, we will be able to record rotationally-resolved gas-phase spectra, enabling interstellar searches for these species. The SCRIBES instrument requires a source of rotationally cold ions, and this has been accomplished by coupling a supersonic expansion with an electric discharge. Other groups (e.g. Thaddeus and McCarthy at Harvard, Salama et. al at NASA-Ames) have produced cold ions in a similar fashion, but always with a pulsed discharge source. Due to our need for a continuous ion source for SCRIBES, we have designed a continuous supersonic expansion discharge nozzle. We will discuss the various design factors considered during the construction of our continuous self-aligning cold ion source. TE05 15 min 9:38 PERFORMANCE OF A CONTINUOUS SUPERSONIC EXPANSION DISCHARGE NOZZLE EVALUATED BY LASER-INDUCED FLUORESCENCE SPECTROSCOPY KYLE N. CRABTREE, CARRIE A. KAUFFMAN, Department of Chemistry, University of Illinois, Urbana, IL, 61801; BENJAMIN J. MCCALL, Departments of Chemistry and Astronomy, University of Illinois, Urbana, IL, 61801. We have recently constructed a prototype continuous supersonic expansion discharge nozzle for the production of rotationally cold molecular ions. To assess the performance of this source, we have employed laser-induced fluorescence spectroscopy to measure the rotational temperature distributions of I and N as a function of position within the expan sion. These measurements are performed on the · (6-0), (8-1), (10-2), and (12-3) bands of I at 608 nm and the (4-0) band of N at 614 nm using a tunable cw dye laser. The temperature distributions obtained act as a feedback mechanism that aids in refinement of the source design with the aim of optimizing the densities and temperatures of the species within the expansion. 143 TE06 PROGRESS IN THE DEVELOPMENT OF AN INFRARED ION BEAM SPECTROMETER 15 min 9:55 KYLE B. FORD, ANDREW A. MILLS, HOLGER KRECKEL, MANORI PERERA and KYLE N. CRABTREE, Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, IL 61801.; BENJAMIN J. McCALL, Departments of Chemistry and Astronomy, University of Illinois at Urbana-Champaign, Urbana, IL 61801.. Spectroscopic analysis of molecular ions is generally performed using a plasma discharge to produce the ion of interest. However, spectroscopy of the ions is complicated by the high temperatures and abundance of neutrals found in a plasma. The technique of velocity modulation has been effective in selectively measuring the spectra of ions while discriminating against the spectra of the considerably more abundant neutral molecules, but it has only been applied to fairly high temperature plasmas. Supersonic expansions have been profitably used to cool molecular ions to low temperatures, but they have not been used in combination with an ion-selective technique. We are aiming to develop an instrument which can provide both cold ions and effective separation of ions from neutrals. Specifically, we are improving the ”direct laser absorption spectroscopy in a fast ion beam” technique developed in the Saykally group a. Our instrument will produce rotationally cold ions in a supersonic discharge source, then accelerate and manipulate them with ion optics. This ion beam will be steered into a field-free drift region, which will separate it from neutrals and make it collinear with a high finesse cavity to be probed with continuous wave cavity ringdown spectroscopy (cw-CRDS). This instrument, which we call SCRIBES (Sensitive Cooled Resolved Ion Beam Spectroscopy), will have the additional advantages of a sub-Doppler line width and mass-dependent Doppler splitting. Additionally, a time of flight mass spectrometer at the end of the apparatus will identify the species in the ion beam. We will report the progress that has been made in maximizing the ion current in the drift region, including progress in source design. We will also introduce the second generation instrument. Improvements over the previous design will be discussed, as well as advancements in the characterization and optimization of the instrument. a J. V. Coe, J. C. Owrutsky, E. R. Keim, N. V. Agman, D. C. Hovde, and R.J. Saykally J. Chem. Phys. 90, 3893 1989. TE07 ABSORPTIONS BETWEEN 3000 AND 5500 cm 15 min OF NORMAL AND OXYGEN-18 ENRICHED O 10:12 AND O TRAPPED IN SOLID NEON MARILYN E. JACOX and WARREN E. THOMPSON, Optical Technology Division, National Institute of Standards and Technology, Gaithersburg, MD 20899-8441. Very recently, Ricks, Douberly, and Duncan a have assigned absorptions in the 3000 to 4300 cm spectral region to combination bands of gas-phase cyc-O . Other experiments by Kelley, Robertson, and Johnson b identified vibronic bands between 4000 and 5300 cm of gas-phase O complexed with an argon atom. Absorptions corresponding to these bands have been observed in the present experiments for both cyc-O and O , as well as for several of their isotopologues trapped at 4.3 K in solid neon. The results will be compared with the gas-phase data, and possible assignments will be considered taking into account the results of isotopic substitution. a A. b J. M. Ricks, G. E. Douberly, and M. A. Duncan, Int. J. Mass Spectrom., doi:10.1016/j.ijms.2009.01.009 (2008). A. Kelley, W. H. Robertson, and M. A. Johnson, Chem. Phys. Lett. 362, 255 (2002). Intermission 144 TE08 15 min CORRELATED AB INITIO STUDY OF THE GROUND ELECTRONIC STATE OF THE H –O COMPLEX 10:45 WAFAA M. FAWZY, Department of Chemistry, Murray State University, Murray, KY 42071. The H –O (X ) complex has been examined using the coupled-cluster theory at the CCSD(T)/aug-cc-pVDZ and CCSD(T)/aug-cc-pVTZ levels. Electronic structure calculations show that the global minimum energy structure corresponds to a planar bent geometry with a well depth of 1550 cm . For this geometry, the distance between centers of masses of moieties of the complex is 2.57 Å, angstroms and the angles between the internuclear axes of the superoxide radical and the hydrogen molecule with respect to the axis that connects their centers of masses are Æ and Æ , respectively. These results indicate that the hydrogen molecule and the superoxide radical are held together by a strong hydrogen bond within the complex. Results of the current work will be discussed and compared to results of our recent ab initio studya of the H –O (X ) complex. a Wafaa M. Fawzy, in preparation for publication TE09 15 min 11:02 MASS-ANALYZED THRESHOLD IONIZATION OF LANTHANUM OXIDE CLUSTERS: La O AND La O LU WU, CHANGHUA ZHANG, SERGIY KRASNOKUTSKI, and DONG-SHENG YANG, Department of Chemistry, University of Kentucky, Lexington, KY 40506-0055. Lanthanum oxide clusters are produced by laser vaporization in a pulsed cluster source and identified by photoionization mass spectrometry. Vibrationally resolved ion spectra are obtained with mass-analyzed threshold ionization (MATI) spectroscopy. The MATI spectra of La O and La O exhibit a very strong 0-0 transition, indicating similar geometries for the neutral and ionized clusters and a very weakly bonding or non-bonding electron ejected from an outmost molecular orbital. The ionization energies of La O and La O are measured to be 36937(5) and 28028(5) cm , respectively. In addition, the spectra of both clusters display a number of vibrational intervals that are associated with metal-metal, metal-oxygen, and oxygen-oxygen vibrations. Preliminary data analysis shows that the La O cluster has a D planar structure and La O has a C cage-like structure, both with alternating La-O-La bonds. The spectra may be assigned to the Ag Ag transition in the case of La O and A A in La O . TE10 MICROWAVE DETECTION OF PROTONATED SO IN TWO ISOMERIC FORMS 15 min 11:19 V. LATTANZI, M.C. MCCARTHY, and P. THADDEUS, Harvard-Smithsonian Center for Astrophysics, 60 Garden St., Cambridge, MA 02138, and School of Engineering & Applied Sciences, Harvard University, 29 Oxford St., Cambridge, MA 02138; SVEN THORWIRTH, Max-Planck-Institut f ür Radioastronomie, Auf dem Hügel 69, 53121 Bonn, Germany. By means of Fabry-Pérot FT microwave spectroscopy, the rotational spectrum of protonated sulfur dioxide in two distinct isomeric forms, a cis and a trans geometry, is reported. Searches for both isomers were based on theoretical structures obtained at the CCSD(T)/cc-pwCVQZ level of theory corrected for zero-point vibrational effects at the CCSD(T)/ccpV(T+)Z level. At a similarly high level of theory, the cis isomer is calculated to be the global minimum on the potential energy surface, but the trans isomer is predicted to lie only a few kcal/mol higher in energy. The identification of cis HOSO has been confirmed by detection of rotational lines of DOSO and HO SO at precisely the expected frequency shifts. Because sulfur dioxide is a well known interstellar and extragalactic species, and because it possesses a large proton affinity, HOSO is a excellent candidate for radioastronomical detection. 145 TE11 10 min A LABORATORY AND THEORETICAL STUDY OF PROTONATED CARBON DISULFIDE, 11:36 HSCS M. C. MCCARTHY, P. THADDEUS, Harvard-Smithsonian Center for Astrophysics, 60 Garden St., Cambridge, MA 02138, and School of Engineering & Applied Sciences, Harvard University, 29 Oxford St., Cambridge, MA 02138; JEREMIAH J. WILKE AND HENRY F. SCHAEFER III, Center for Computational Chemistry, University of Georgia, 1004 Cedar St, Athens, GA 30602. The rotational spectrum of protonated carbon disulfide, HSCS , has been detected in the centimeter-wave band in a molecular beam by Fourier transform microwave spectroscopy. Rotational and centrifugal distortion constants have been determined from transitions in the ' ladder of the normal isotopic species, HS CS , and DSCS . The present assignment agrees well with high-level coupled cluster calculations of the HSCS structure, which, like earlier work, predict this isomer to be the ground state on the HCS potential energy surface; HCSS , an isomer with symmetry, is predicted to lie more than 20 kcal/mol higher in energy. Other properties of HSCS including its dipole moment, vibrational frequencies, and infrared intensities have also been calculated at the CCSD(T)/cc-pwCVQZ level of theory. Because carbon disulfide possesses a fairly large proton affinity, and because this nonpolar molecule may plausible exist in astronomical sources, HSCS is a good candidate for detection with radio telescopes in the sub-millimeter band where the stronger *-type transitions of this protonated cation are predicted to lie. TE12 INFRARED SPECTROSCOPY AND STRUCTURE OF PROTONATED BENZENE CLUSTERS 15 min 11:48 B. BANDYOPADHYAY, T. CHENG, M. A. DUNCAN, Department of Chemistry, University of Georgia, Athens, GA 30602-2556. Gas phase protonated benzene clusters are produced in a pulsed electrical discharge supersonic expansion cluster source. Infrared spectra of the cold argon-tagged species are obtained via infrared photodissociation spectroscopy. Theoretical investigations have been employed to probe the structures of these clusters. The infared spectroscopy (1000 cm to 3500 cm ) and structures of the protonated benzene dimer , trimer and tetramer will be discussed. Infrared spectrum of protonated benzene dimer shows a peak around 2840 cm corresponding to the sp CH stretch of the benzene ring. In the case of the trimer and tetramer, this peak is shifted down to 2640 cm , suggesting that the CH moiety of the protonated benzene is interacting with another benzene. Various possible isomeric structures are explored theoretically, but the infrared spectrum of protonated benzene dimer suggests the prescence of exclusively one isomer. 146 TF. RADICALS AND IONS TUESDAY, JUNE 23, 2009 – 1:30 PM Room: 160 MATH ANNEX Chair: HANNA REISLER, University of Southern California, Los Angeles, California TF01 LOW-ENERGY PHOTOELECTRON IMAGING SPECTROSCOPY OF ANIONS 15 min 1:30 CHRISTOPHER L. ADAMS, and J. MATHIAS WEBER, JILA, NIST, and Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309, USA; KENT M. ERVIN, Department of Chemistry, University of Nevada, Reno, 1664 N. Virginia St. MS 216, Reno, NV 89557-0216. We report on photoelectron emission from nitroalkane anions using low-energy velocity map photoelectron imaging. The excess electron of these radical anions is weakly bound with adiabatic electronic affinities around 1500 cm with relatively benign sensitivities to the length of the alkane chain. In addition to conventional photoelectron spectroscopy, we use vibrational excitation of the CH stretching vibration (2700-3000 cm ) to induce vibrational autodetachment. We have obtained an improved value for the adiabatic electron affinity (172 6 meV), and definitively assigned the vibrational features in the photoelectron spectrum of the nitromethane anion. In addition, the vibrational autodetachment spectrum offers insight into vibrational modes involved in vibrational autodetachment. TF02 INFRARED SPECTROSCOPY OF HYDRATED NITROMETHANE ANIONS 15 min 1:47 JESSE C. MARCUM, J. MATHIAS WEBER, JILA, NIST, and Department of Chemistry and Biochemistry, University of Colorado, Boulder, CO 80309-0440. The hydration of molecular anions is still not as thoroughly explored as for atomic anions. We present IR spectra and quantum chemical calculations of hydrated nitromethane anions. In the monohydrate, the nitro group of the ion interacts with the water molecule via two hydrogen bonds, one from each O atom. This motif is partially conserved in the dihydrate. Adding the third water molecule results in a ring-like structure of the water ligands, each of which forms one H bond to one of the O atoms of the nitro group and another to a neighboring water ligand, reminiscent of the hydration motif of the heavier halides. Interestingly, while the methyl group is not directly involved in the interaction with the water ligands, its infrared signature is strongly affected by the changes in the intramolecular charge distribution through hydration. 147 TF03 NEGATIVE ION PHOTOELECTRON SPECTRA OF HALOMETHYL ANIONS 15 min 2:04 KRISTEN M. VOGELHUBER, SCOTT W. WREN, JILA, University of Colorado and National Institute of Standards and Technology, and Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309; ANNE B. McCOY, Department of Chemistry, The Ohio State University, Columbus, Ohio 43210; KENT M. ERVIN, Department of Chemistry and Chemical Physics Program, University of Nevada, Reno, Nevada 89557; W. CARL LINEBERGER a , JILA, University of Colorado and National Institute of Standards and Technology, and Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309. Halomethyl anions undergo a significant geometry change upon electron photodetachment, resulting in multiple extended vibrational progressions in the photoelectron spectra. The normal mode analysis that successfully models photoelectron spectra when geometry changes are modest is unable to reproduce the experimental data using physically reasonable parameters. A three-dimensional anharmonic coupled-mode analysis was employed to accurately reproduce the observed vibrational structure. We present the 364 nm negative ion photoelectron spectra of the halomethyl anions CHX and (X = Cl, Br, I) and report electron affinities, vibrational frequencies, and geometries. CDX a Support from NSF and AFOSR is gratefully acknowledged TF04 NEW ABSORPTION SPECTRA OF CH NEAR 780 NM 15 min 2:21 JU XIN, Department of Physics and Engineering Technology, Bloomsburg University, 400 East Second Street, Bloomsburg PA 17815-1301; ZHONG WANG and TREVOR J. SEARS, Department of Chemistry, Brookhaven National Laboratory, Upton, New York 11973 and Department of Chemistry, Stony Brook University, Stony Brook, New York 11794. The near infrared and visible spectrum ( * ) of singlet CH has been the subject of much study. However, the region between the red end of the visible part of the spectrum and about 800 nm has not been recorded since the pioneering work of Herzberg and Johns. a We have remeasured the absorption spectrum between approximately 769 and 806 nm at near shot-noise-limited sensitivity and Doppler-limited resolution using a frequency-modulated extended cavity diode laser source. Rotational branches in 7 vibronic bands involving ' have been assigned using known ground state combination differences. Most of them have not previously been observed and some reassignments of the Herzberg and Johns analysis have been made. Comparison with the most complete available calculated ro-vibronic energy level structureb helped considerably in making the assignments, and the observed vibronic levels are assigned to levels of both and * electronic character. The calculated energy levels show moderate, up to 10 cm , apparently random, differences from the observed levels The new data will certainly help to refine the singlet potential and also provide additional avenues for future kinetics and dynamics studies of the radical. Acknowledgments: Work at Brookhaven National Laboratory was carried out under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy. Ju Xin acknowledges support from the Faculty and Student Teams program of the Educational Programs Department at Brookhaven National Laboratory. a G. b J. Herzberg and J. W. C. Johns Proc. R. Soc. London Ser. A, 295, 107 (1966) -P. Gu, G. Hirsch, R J Buenker, M. Brumm, G. Osmann, P. R. Bunker and P. Jensen J. Molec. Struc., 517-8, 247 (2000) 148 TF05 15 min 2:38 FINDING THE ELUSIVE IODOCARBENE: FLUORESCENCE EXCITATION AND SINGLE VIBRONIC LEVEL EMISSION SPECTROSCOPY OF CHI C. TAO, C. EBBEN, H. T. KO AND S. A. REID, Department of Chemistry, Marquette University, Milwaukee, WI 53233; Z. WANG AND T. J. SEARS, Department of Chemistry, Brookhaven National Laboratory, Upton, NY 11973. Among the triatomic halocarbenes, only the iodocarbenes remain to be characterized. The search for these elusive species is motivated by a controversy regarding the multiplicity of the ground state. Photoelectron spectra of Lineberger and coworkers a suggest a triplet ground state for CHI, at variance with recent * 9 99 studies, which suggest a singlet ground state with a singlet-triplet gap of around 4 kcal mol . In this work, we have succeeded in finding the spectra of CHI and its deuterated isotopomer using pulsed discharge jet spectroscopy. Rotationally resolved fluorescence excitation spectra are consistent with a singlet-singlet transition, and the derived rotational constants are in good agreement with theoretical predictions. Single vibronic level emission spectra confirm a singlet multiplicity for the ground state, and reveal extensive mixing of the singlet and triplet levels at higher energy. We are able to set a lower limit on the singlet-triplet gap of 4.1 kcal mol , in excellent agreement with theory. Extrapolation of the observed bending levels for CHI and CDI to a common origin suggests that the origin of the state lies near 10 500 cm , and we will report on high resolution measurements near the electronic origin made at Brookhaven National Laboratory. a M. K. Gilles, K. M. Ervin, J. Ho, and W. C. Lineberger, J. Phys. Chem. 96, 1130 (1992). TF06 15 min 2:55 FINE AND HYPERFINE STRUCTURE IN SUB-DOPPLER, INFRARED, CH-STRETCHING SPECTRA OF MONODEUTERATED METHYL RADICAL MELANIE A. ROBERTS, CHANDRA SAVAGE, FENG DONG, DAVID J. NESBITT, JILA, National Institute of Standards and Technology and University of Colorado, and Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309. High resolution direct absorption spectroscopy in the CH-stretching region is used to observe fully resolved rovibrational structure and partially resolved fine and hyperfine structure of monodeuterated methyl radical (CH D). CH D is readily made by passing a mixture of CH DI and Ne/He through the orifice of a slit nozzle and striking a discharge, which supersonically expands to permit spectroscopic study of radicals with a rotational temperature of approximately 15 K and slit-narrowed IR line widths of 0.002 cm . We obtained and analyzed rovibrational transitions in both the symmetric and antisymmetric CH-stretch regions. We also observed fine and hyperfine structure, arising from interactions between electron spin with molecular rotation and with H/D nuclear spins, respectively. This structure results in complex lineshapes under sub-Doppler resolution. Simultaneous least squares fitting of the set of spectral profiles is used to extract rotational, spin-rotation and Fermi contact information in the ground and vibrationally excited states. 149 TF07 15 min 3:12 HIGH RESOLUTION DIRECT ABSORPTION SPECTROSCOPY OF HYDROXYMETHYL RADICAL IN THE MID-INFRARED MELANIE A. ROBERTS, ERIN N. SHARP-WILLIAMS, DAVID J. NESBITT, JILA, National Institute of Standards and Technology and University of Colorado, and Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309. Hydroxymethyl radical has a rich history in the literature, with over 100 theoretical and experimental papers, and is an important molecule in both atmospheric and combustion chemistry. We recently obtained high resolution direct absorption spectra for CH-stretch excitation of hydroxymethyl radical, with fully resolved rovibrational bands in the mid-IR, by taking advantage of the low rotational temperatures and sub-Doppler linewidths obtained in a slit supersonic expansion. Jet cooled hydroxymethyl radical is formed by striking a discharge over a mixture of methanol and Ne/He carrier gas at the slit orifice of a nozzle. The rovibrational transitions are fit to a Watson A-reduced asymmetric top Hamiltonian to yield improved rotational constants and new insights into the large amplitude dynamics in this important radical species. The results both augment and make for interesting comparison with previous studies by Feng et al a , which were based on double resonance ionization detected IR methods to obtain moderate resolution spectra in the CH- and OH-stretching region. a L. Feng, J. Wei and H. Reisler, J. Phys. Chem. A 108, 7903 (2004). Intermission TF08 15 min 3:45 IMPROVEMENT OF THE ANALYSIS OF THE PEROXY RADICALS USING AN EVOLUTIONARY ALGORITHM GABRIEL M. P. JUST, PATRICK RUPPER AND TERRY A. MILLER, Department of Chemistry, The Ohio State University, 120 W. 18th Ave., Columbus OH, 43210; W. LEO MEERTS, Molecular and Biophysics group, Institute for Molecules and Materials, Radboud University Nijmegen, P.O. Box 9010, NL-6500 GL Nijmegen, The Netherlands. For quite awhile, our laboratory has had interest in the organic peroxy radicals which are relevant to atmospheric chemistry as well as low temperature combustion. We first studied these radicals via room temperature cavity ringdown spectroscopy (CRDS). We continued our investigation of the same radicals using a quasi-Fourier-transform laser source using a supersonic jet expansion in order to obtain partially rotationally resolved spectra which are nearly doppler limited. In order to analyze our spectra we decided to complement our conventional least-square-fit method of simulating spectra by using a evolutionary algorithm (EA) approach which uses both the frequency and the intensity information that are contained in our dense and complicated spectra. This presentation will focus on the CD O spectrum to demonstrate the capabilities and the quality of the fits obtained via the EA method and compare it with the traditional least-square-fit method. 150 TF09 15 min 4:02 ANALYSIS OF THE CAVITY RINGDOWN SPECTRA OF THE SMALLEST JET-COOLED ALKYL PEROXY RADICALS USING A EVOLUTIONARY ALGORITHM GABRIEL M. P. JUST, PATRICK RUPPER AND TERRY A. MILLER, Department of Chemistry, The Ohio State University, 120 W. 18th Ave., Columbus OH, 43210; W. LEO MEERTS, Molecular and Biophysics group, Institute for Molecules and Materials, Radboud University Nijmegen, P.O. Box 9010, NL-6500 GL Nijmegen, The Netherlands. Alkyl peroxy radicals long have been well known to be key intermediates in atmospheric chemistry as well as in low temperature combustion. For the last several years, our group has generated a data set for these radicals using room temperature cavity ringdown spectroscopy. We have recently extended our investigations of these radicals to obtain a similar data set of spectra under jet cooled conditions using a quasi-Fourier-transform-limited laser source, a supersonic slit jet expansion, and a discharge. We were able to observe partially rotationally resolved spectra of isomers and conformers of several peroxy radicals such as methyl peroxy, CH O /CD O , ethyl peroxy, C H O and C D O , propyl peroxy, C H O , and phenyl peroxy, C H O . To analyze our results we employed a new approach by using the evolutionary algorithm method, whereby we can effectively use both the frequency and the intensity information contained in the experimental spectra. This presentation will focus on the results from our fitted spectra which were obtained using this semi-automated method and will demonstrate the power of our technique . TF10 15 min 4:19 HIGH RESOLUTION INFRARED SPECTROSCOPY OF JET-COOLED PHENYL RADICAL IN THE GAS PHASE ERIN N. SHARP-WILLIAMS, MELANIE A. ROBERTS, DAVID J. NESBITT, JILA, National Institute of Standards and Technology and University of Colorado, and Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309. Phenyl radical (C H ) is one of the most important reactive intermediates, as it is formed from the homolytic cleavage of a CH bond in benzene (C H ), and hence it plays a central role in the combustion of fossil fuels that are typically rich in aromatics. We recently recorded the first high resolution infrared spectra of jet-cooled phenyl radical in the gas phase. This was obtained by direct absorption laser spectroscopy in a slit-jet discharge supersonic expansion of a phenyl halide precursor (C H X, 9%0% C H I and C H Br) diluted in a Neon/Helium gas mixture. We observed an A-type band, which arises from a fundamental excitation of the out-of-phase symmetric CH stretch ( ). The unambiguous assignment of the rotational structure in this band to C H is facilitated by comparing 2-line combination differences with the Fourier transform microwave (FTM) and direct absorption millimeter-wave (mm-wave) measurements of the ground state by McMahon 0 =% a . A least-squares fit to an asymmetric top Hamiltonian of the rotationally-resolved vibrational band is done to determine upper-state rotational constants and a gas-phase band origin ( ) of 3071.8904 (10) cm . This is in very good agreement with the value of 3071 cm for the out-of-phase symmetric CH stretch of phenyl reported by Friderichsen 0 =%b from matrix isolation studies, which indicates a surprisingly small red shift due to the low-temperature argon environment. a R. J. McMahon, M. C. McCarthy, C. A. Gottlieb, J. B. Dudek, J. F. Stanton and P. Thaddeus, Ap. J. 590, L61 (2003). J. G. Radziszewski, M. R. Nimlos, P. R. Winter, D. C. Dayton, D. E. David and G. B. Ellison, J. Am. Chem. Soc. 123, 1977 (2001). b A. V. Friderichsen, 151 TF11 15 min 4:36 SPECTRUM OF ETHYNYL RADICAL: NEW INSIGHTS INTO THE SPECREINVESTIGATING THE TROSCOPY OF VIBRONIC BANDS ERIN N. SHARP-WILLIAMS, MELANIE A. ROBERTS, DAVID J. NESBITT, JILA, National Institute of Standards and Technology and University of Colorado, and Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309; ROBERT F. CURL, Department of Chemistry and Rice Quantum Institute, Rice University, Houston, Texas 77005. The ethynyl radical, C H, is an important reactive intermediate both in combustion processes, as it is readily formed in an acetylene (C H ) flame, and in the chemistry of the interstellar medium, where it is suspected to be involved in the formation of longer carbon chain species (C H). We have recently interrogated several of the vibronic transitions to the lowlying excited state from the vibrationless level of the ground electronic state via high resolution infrared spectroscopy. This was done using direct absorption laser spectroscopy in a slit-jet discharge supersonic expansion of C H diluted in a Neon/Helium gas mixture. In comparing our spectra with those already published using magnetic rotation spectroscopy a b , we find discrepancies between rovibronic frequencies in the 0 band at 3600 cm . The inconsistency is localized in the excited state, by comparison of 2-line combination differences with mm-wave measurements of the ground state by Thaddeus and coworkers c. Calculating the energy levels using both Hund’s case (a) and (b) basis sets and revisiting the analysis in the aforementioned work, we have determined that the discrepancies arise from a parity mislabeling of the lambda-doubled excited states. The improved low J signal intensities and resolution of satellite transitions that are observable under sub-Doppler, jet-cooled conditions complement the previous data and permit refinement of the rotational, spin-rotational, and lambda-doubling constants. a W. B. Yan, C. B. Dane, D. Zeitz, J. L. Hall and R. F. Curl, J. Mol. Spectrosc. 123, 486 (1987). F. Curl, P. G. Carrick and A. J. Merer, J. Chem. Phys. 82, 3479 (1985). c T. C. Killian, C. A. Gottlieb and P. Thaddeus, J. Chem. Phys. 127, 114320 (2007). b R. TF12 15 min 4:53 AND ABSORPTIONS OF NO TRAPPED IN SOLID NEON THE MARILYN E. JACOX and WARREN E. THOMPSON, Optical Technology Division, National Institute of Standards and Technology, Gaithersburg, MD 20899-8441. transition of normal and isotopically substituted NO have been observed between Absorptions arising from the 7500 and 9500 cm . Details of the spectra will be discussed and assignments will be proposed. Absorptions arising transition of NO , with band origin near 15 000 cm , have also been observed for the normal species from the and two of its isotopologues which possess D symmetry. As in the gas phase, the absorptions are broadened because of predissociation. The observed band structure corresponds closely with that reported for the gas-phase molecule. 152 TF13 15 min 5:10 JET-COOLED LASER SPECTROSCOPY OF A JAHN-TELLER AND PSEUDO JAHN-TELLER ACTIVE MOLECULE: THE NITRATE RADICAL MING-WEI CHEN, Laser Spectroscopy Facility, Department of Chemistry, The Ohio State University, 120 W. 18th Avenue, Columbus, Ohio 43210; KANA TAKEMATSU, MITCHIO OKUMURA, Arthor Amos Noyes Laboratory of Chemical Physics, California Institute of Technology, Pasadena, California 91125; and TERRY A. MILLER, Laser Spectroscopy Facility, Department of Chemistry, The Ohio State University, 120 W. 18th Avenue, Columbus, Ohio 43210. Well-known as an important intermediate in atmospheric chemistry, the nitrate radical (NO ) has been extensively stud , , and ) ied both experimentally and theoretically. The three energetically lowest electronic states ( are strongly coupled by vibronic interactions and hence it is a textbook molecule for understanding the coupling between nearby potential energy surfaces. Such coupling has been treated in considerable detail theoretically. a However, corresponding experimental characterization of the interaction is much less detailed. The experimental results primarily consist transition of IR measurements of vibrational transitions in the ground state. bc In addition, the electronically forbidden - d has been observed in ambient temperature CRDS studies. To understand both the Jahn-Teller and pseudo Jahn-Teller coupling in the molecule, further measurements are required with different selection rules and/or higher resolution to resolve the rotational structures of different transitions. In our group, a high-resolution (source 100 MHz in NIR region), transition. Furthermore, jet-cooled CRDS systeme can be applied to rotationally resolve the electronically forbidden - our high-resolution LIF/SEP system (source 100 MHz) can provide the direct, rotationally resolved measurements - and - transitions by operating in the LIF and SEP modes respectively. Such data can provide unambiguous of the , and states. spectral assignments in the a J. F. Stanton, J. Chem. Phys., 126, 134309 (2007) Kawaguchi, E. Hirota, T. Ishiwata, and I. Tanaka, J. Chem. Phys., 93, 951 (1990) c K. Kawaguchi, T. Ishiwata, E. Hirota, and I. Tanaka, Chem. Phys., 231, 193 (1998) d A. Deev, J. Sommar, and M. Okumura, J. Chem. Phys., 122, 224305 (2005) e S. Wu, P. Dupr , and T. A. Miller, Phys. Chem. Chem. Phys., 8, 1682, (2006) b K. TF14 INFRARED VACUUM ULTRAVIOLET SPECTROSCOPY OF ALLYL RADICAL 10 min 5:27 B. REED, C. S. LAM, X. XING, K. C. LAU, C. Y. NG, Department of Chemistry, University of California, Davis, CA 95616; X. ZHANG, Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109; A. VASILIOU, G. B. ELLISON, University of Colorado, Boulder, CO 80309. An infrared (IR)-vacuum ultraviolet (VUV) double resonance experiment on the allyl (CH CHCH ) radical will be described. The pulsed field ionization-photoelectron (PFI-PE) spectrum of the allyl (CH CHCH ) radical has already been obtained and used to determine the accurate ionization energy of 65 584.6 +/- 2.0 cm (8.131 46 0.000 25 eV). Next, building on previous work which identified IR resonances at 3113.98 and 3110.59 cm , we anticipate the first IR-VUV double resonance spectrum of the allyl (CH CHCH ) radical. We have shown previously that high-resolution IR spectra of polyatomic neutral closed shell molecules can be obtained with high sensitivity by scanning the frequency of a single mode infrared optical parametric oscillator (IR-OPO) laser to excite the molecular species of interest and fixing the frequency of a tunable vacuum ultraviolet (VUV) laser to photoionize the IR excited species. The fact that this IR-VUV method is based on a VUV photoionization probe together with time of flight (TOF) mass spectrometry (MS) detection allows the identification of the neutral IR absorber, making the method applicable for IR spectroscopy measurements of radicals, isotopomers, and clusters, which normally exist as impure samples. 153 TF15 15 min 5:39 SPECTROSCOPIC IDENTIFICATION OF p-CHLORO--METHYLBENZYL RADICAL IN THE GAS PHASE SEUNG WOON LEE, GI WOO LEE, SANG KUK LEE, Department of Chemistry and the Chemistry Institute of Functional Materials,Pusan National University, Pusan 609-735, Republic of Korea. We report the first spectroscopic identification of the p-fluoro--methylbenzyl radical in the gas phase. Precursor p-fluoroethylbenzene seeded in a large amount of inert carrier gas helium was electrically discharged to produce the benzyl-type radicals in a corona excited supersonic expansion using a pinhole-type glass nozzle, from which the vibronic emission spectrum was recorded in the visible region using a long path monochromator. From an analysis of the spectrum observed, we found the formation of p-fluoro--methylbenzyl radical as well as p-fluorobenzyl radical in the jet from the precursor. After eliminating the bands belonging to p-fluorobenzyl radical using the known data, a we identified spectroscopically the formation of the p-fluoro--methylbenzyl radical, in which the energy of the D D electronic transition and a few vibrational mode frequencies in the ground electronic state were determined by comparison with those from an ab initio calculation and with those from the known data of the precursor. a S. K. Lee and D. Y. Baek Chem. Phys. Lett. 301(3-4), 407-412 (1999). 154 TG. INFRARED/RAMAN TUESDAY, JUNE 23, 2009 – 1:30 PM Room: 170 MATH ANNEX Chair: CAROLYN BRAUER, Jet Propulsion Laboratory, Pasadena, California TG01 FOURIER TRANSFORM SPECTROSCOPY WITHOUT MICHELSON INTERFEROMETER 15 min 1:30 J. MANDON, P. JACQUET, M. JACQUEY, G. GUELACHVILI, N. PICQU É, Laboratoire de Photophysique Moléculaire, CNRS, Bâtiment 350, Université Paris-Sud, 91405 Orsay cedex, France; B. BERNHARDT, R. HOLZWARTH, T.W. HÄNSCH, Max Planck Institut für Quantenoptik, Hans-Kopfermann-Str. 1, 85748 Garching, Germany. Michelson interferometers have been for decades the main component of Fourier transform spectrometers. With the advent of femtosecond frequency combs, which exhibit a broadband spectrum made of equidistant frequency markers, this obviousness is called into question. In this contribution, we report on Fourier transform spectroscopy based on two frequency combs (FC-FTS). FC-FTS bears on the same physical principle as traditional FTS. It has however some distinct important advantages related to the absence of moving part and to the metrological qualities of laser frequency combs. FC-FT spectrometers are compact and able to provide highly-resolved and sensitive broadband spectra of single events. Acquisition time is of the order of a few tens of microseconds for Doppler-limited resolution. Furthermore, it is now possible to routinely record, within a few seconds, Fourier spectra which typically exhibit kHz optical resolution, improving by one million the standard GHz resolution of Michelson-based FTS. Our technique for multiplex accessing of Hertz-level-self-calibrated spectra with negligible instrumental lineshape opens intriguing perspectives in intermediate metrology of molecular lineshapes and outperforms Fourier transform spectroscopy based on the Michelson interferometer. 155 TG02 15 min 1:47 PRECISION FOURIER TRANSFORM SPECTROSCOPY WITH FEMTOSECOND FREQUENCY COMBS P. JACQUET, J. MANDON, G. GUELACHVILI, N. PICQU É, Laboratoire de Photophysique Mol éculaire, CNRS, Bâtiment 350, Université Paris-Sud, 91405 Orsay cedex, France; B. BERNHARDT, R. HOLZWARTH, T.W. HÄNSCH, Max Planck Institut für Quantenoptik, Hans-Kopfermann-Str. 1, 85748 Garching, Germany. Fourier transform spectrometers play a crucial and intensive role in molecular spectroscopy. However, these instruments, most often based on Michelson 2300 Hz 7.7 10-8 cm-1 interferometers, are presently unable to address some of the new challenges associated with fundamental experiments or optical diagnostic. In recent years, femtosecond frequency combs, which are new laser sources exhibiting an optical spectrum made of very sharp and uniformly spaced lines, have revolutionized the field of frequency metrology. They lead also to the implementation of a new kind of Fourier interferometers, where two frequency combs with slightly different repetition rates beat with each other. These spectrometers may bring remarkable characteristics, amongst which extremely short measurement time. -1 6484.127 cm -1 We report on the implementation of an original and simple set-up for fre- 6483.930 cm quency comb Fourier transform spectroscopy, which reaches the unprecedented resolution of 1 kHz within 6 s recording time. Moving mirror of equivalent Michelson interferometers should cover 130 km path-difference excursion at 10 km.s velocity. We also record simultaneously Doppler-limited dispersion and absorption spectra within a few tens of microseconds. The comb structure of the light source provides self-calibration of the wavenumber scale. Precision spectroscopy of the overtone spectrum of acetylene, in the 1.5 m range, is reported as a first demonstration. TG03 INFRARED SPECTROSCOPY USING QUANTUM CASCADE LASERS 15 min 2:04 PENG WANG, TOM J. TAGUE , Bruker Optics, Billerica, MA 01821; LAURENT DIEHL, CHRISTIAN PFLÜGL, and FEDERICO CAPASSO, School of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138. A single Fabry-Perot quantum cascade laser (QCL, bandwidth 60cm-1) operated in continuous mode at 283K on a thermoelectric cooler has been combined with Fourier-transform infrared (FTIR) spectrometers for transmission measurement through strongly absorbing samples or samples in strongly absorbing solvents. Because of the high brightness of the QCL device, absorption features of many optically dense media can be investigated directly in transmission mode, which are usually not accessible with standard globar light sources used typically in FTIRs. Applications include but not limited to analysis of proteins in water solutions, tissues, thick films and tablets etc. 156 TG04 10 min 2:21 THE AILES IR AND THZ HIGH RESOLUTION SPECTROSCOPY BEAMLINE AT SOLEIL : CHARACTERISTICS AND PERFORMANCES PASCALE ROY, JEAN-BLAISE BRUBACH, MATHIEU ROUZIÈRES, MICHEL VERVLOET, OLIVIER PIRALIa , DIDIER BALCON , FRIDOLIN KWABIA-TCHANAb , LAURENT MANCERONc , Synchrotron SOLEIL, L’Orme des Merisiers, Saint-Aubin - BP 48, 91192 Gif-sur-Yvette CEDEX, France. A new infrared beamline (Beamline AILES) is now operating at the third generation Synchrotron Radiation source SOLEIL near Saclay, France. This beamline makes use of infrared synchrotron radiation from both edge emission and constant field emission of a bending magnet, with optics optimised for extracting a large solid angle (20 78 mrad ) and thus for operation in the far infrared region and use of high resolution (0.001 cm ) with high flux and brilliance. The expected and measured performances in term of flux, spatial distribution of the photons, spectral range and stability are discussed. Comparison with results obtained with standard laboratory sources show a 5 to 12-fold enhancement in signal-to-noise ratio over the 50 to 500 cm range, for high resolution measurements. The optical system, spectroscopic stations and workspace are described, as well as the beamtime application procedures. a Laboratoire de Photophysique Moléculaire, Université Paris-Sud, 91405 Orsay Cedex, France Interuniversitaire des Systèmes Atmosphériques, CNRS-Paris 7 and 12, UMR 7583, 61 av. du Général de Gaulle, Créteil France c Lab. Dynamique, Interactions et Réactivité, CNRS-UPMC, UMR 7075, case 49, 4 place Jussieu, 75252 Paris Cedex, France b Lab. TG05 15 min 2:33 FIRST HIGH RESOLUTION ABSORPTION SPECTRA USING THE FAR INFRARED SYNCHROTRON CONTINUUM SOURCE EXTRACTED BY THE “AILES” BEAMLINE AT SOLEIL OLIVIER PIRALIa , PASCALE ROY, JEAN-BLAISE BRUBACH, MATHIEU ROUZIÈRES, DIDIER BALCON , LAURENT MANCERONb and MICHEL VERVLOET, Synchrotron SOLEIL, L’Orme des Merisiers Saint-Aubin, 91192 Gif-sur-Yvette, France. In this talk we will present the first high resolution spectra obtained on the Far-Infrared (FIR) AILES beamline at SOLEIL. This bright FIR beam is used as a continuum source for high resolution absorption experiments. For this purpose a multipass cell (baselength of 2.52 m) has been developed in order to reach typical absorption pathlength of 150 m. We will show the absorption spectra of different molecules and the advantages of using FIR synchrotron sources compared to the classical continuum provided by globar and mercury lamps. a Laboratoire b Laboratoire de Photophysique Moléculaire, Université Paris-Sud, 91405 Orsay Cedex, France de Dynamique, Interactions et Réactivité, Université Pierre et Marie-Curie, France TG06 THE FAR-INFRARED BEAMLINE AT THE CANADIAN LIGHT SOURCE 10 min 2:50 BRANT BILLINGHURST, TIM MAY, Canadian Light Source Inc. 101 Perimeter Road, Saskatoon SK, S7N 0X4, Canada. The far-infrared beamline at the Canadian Light Source. is a state of the art facility, which offers significantly more farinfrared brightness than conventional globar sources. While there is the potential to direct this advantage to many research areas, to date most of the effort has been directed toward high-resolution gas phase studies. The infrared radiation is collected from a bending magnet through a 55 X 37 mrad port to a Bruker IFS 125 HR spectrometer, which is equipped with a nine compartment scanning arm, allowing it to achieve spectral resolution better than 0.001 cm . Currently the beamline can achieve signal to noise ratios up to 8 times that which can be achieved using a traditional thermal source. Data from the recently completed commissioning experiments will be presented along with a general overview of the beamline. 157 TG07 15 min 3:02 THE FAR INFRARED SPECTRUM OF THIOPHOSGENE: ANALYSIS OF THE FUNDAMENTAL BAND AT 500 A.R.W. McKELLAR, Steacie Institute for Molecular Sciences, National Research Council of Canada, Ottawa, ON K1A 0R6, Canada; B.E. BILLINGHURST, Canadian Light Source, 101 Perimeter Road, University of Saskatchewan, Saskatoon, SK S7N 0X4, Canada. Thiophosgene (Cl CS) is a model system for studies of vibrational dynamics. Many hundreds of vibrational levels in the ground electronic state have been experimentally observed, allowing a detailed anharmonic force field to be developed including all six vibrational modes. a But there have been no previous high resolution studies of this molecule in the infrared, presumably because its mass and multiple isotopic species result in very congested spectra. Here we report a detailed study of the strong fundamental band (symmetric C Cl stretch) based on a spectrum obtained using synchrotron radiation with the Bruker IFS125 FT spectrometer at the Canadian Light Source far infrared beamline. Thiophosgene is an interesting example of an accidentally near-symmetric oblate rotor. Indeed, its inertial axes switch with isotopic substitution: for Cl CS, the C symmetry axis coincides with the inertial axis, but for Cl CS, this changes to the * axis. Fortunately for us, the ground state microwave spectrum has been well studied. b Even so, it has required the full spectral resolution of the present results, with observed line widths of about 0.0008 , to achieve a true line-by-line analysis. a For b J.H. example: P.D. Chowdary, B. Strickler, S. Lee, and M. Gruebele, Chem. Phys. Letters 434, 182 (2007). Carpenter, D.F. Rimmer, J.G. Smith, and D.H. Whiffen, J. Chem. Soc. Faraday Trans. 2 71, 1752 (1971). TG08 15 min 3:19 MOLECULAR ALIGNMENT EFFECTS IN AMMONIA AT 6.14 m, USING A DOWN-CHIRPED QUANTUM CASCADE LASER SPECTROMETER K. G. HAY, G. DUXBURY and N. LANGFORD, Department of Physics, SUPA, John Anderson Building, University of Strathclyde, 107 Rottenrow, Glasgow G4 0NG, Scotland,UK. In recent intra-pulse experiments in acetylene a we have seen the generation of short emission pulses using the fast frequency down-chirp of a pulsed quantum cascade (QC)laser. These follow the absorptive part of rapid passage signals and are caused by the effects of molecular alignment in low pressure gases. These effects occur when the sweep rate of a laser through a Doppler broadened line is much faster than the collisional relation rate. At higher pressures of the pure gas, a series of free induction decay signals may often be observed. In our current spectrometer using a 6.14 m, laser, in which both the bandwidth of the detection system and the temperature stabilisation of the QC laser itself have been greatly improved, we have been able to study the time dependence of rapid passage effects in ammonia. Using pulses of duration up to 2 microseconds, within which the chirp rate varies from about 100 MHz/ns at the beginning to very slow rate approaching 6 MHz/ns at the end, we can study the interplay between chirp rate and collision processes. By using the base temperature tuning of the laser we can set the centre of the chosen line at the appropriate position within the scan. The absorption path length within our astigmatic Herriott cell is 60 m, so that the gas pressures used are very low. As the QC emission bandwidth chosen lies close to the centre of the band of ammonia, a large number of low J transitions may be studied in detail. a K. G. Hay,G. Duxbury, and N. Langford J. Mod. Opt.55, 3293 2008. Intermission 158 TG09 15 min 3:50 WATER SPECTROSCOPY IN THE 1 m REGION – A CASE STUDY FOR COLLISIONAL NARROWING GEORG WAGNER, MANFRED BIRK, DLR, D 82234 Wessling, Germany. Water spectra in the 1 m region were recorded with the Bruker IFS120HR spectrometer located in Oberpfaffenhofen, Germany. Nineteen measurements in the temperature range 230 to 320 K, water pressures from 1 to 16 mb, and air pressures from 0 to 1000 mb were taken at an absorption path of 80 m. The peak-to-peak noise level was in the order of 0.1%, allowing a detailed study of the line profiles. The Galatry and speed-dependent Voigt profiles were used to fit the lines within the noise level. The dependence of the Dicke narrowing parameter on quantum numbers and pressure will be discussed. A detailed error assessment was performed for using the Voigt profile alone, i.e. omitting Dicke narrowing. Consequences for the spectroscopic database and the retrieval of atmospheric measurements will be described. Spectroscopic parameters together with estimates on the continuum will be discussed. The work was carried out within the WALES project (Water Vapour Lidar Experiment in Space) and supported by the WDC-RSAT (World Data Center for Remote Sensing of the Atmosphere). TG10 15 min 4:07 TIME DEPENDENT MEASUREMENTS OF DICKE NARROWING OF A WATER LINE AT 7.84 MICRONS USING A FREQUENCY DOWN-CHIRPED QC LASER SPECTROMETER K. G. HAY, G. DUXBURY and N. LANGFORD, Department of Physics, SUPA, John Anderson Building, University of Strathclyde, 107 Rottenrow, Glasgow G4 0NG, Scotland,UK ; N. TASINATO, Dipartimento di Chimica Fisica, Universita Ca Foscari di Venezia, 30123 Venezia, Italy. The K doublet and of the of water lies within the tuning range of our frequency down-chirped long pulse 7.84m quantum cascade laser. At the best instrumental resolution of our spectrometer, ca. 0.004 cm , the pair of transitions are unresolved, and appear as a single line strongly affected by Dicke narrowing. Using a pulse duration of 1.3 microseconds the chirp rate varies from approximately 130 MHz/ns at the beginning of the pulse to about 20 MHz/ns at the end. The time taken to sweep through a Doppler broadened half width then varies from 1 ns to about 8 ns. We have exploited these time windows to study the effects of collisions between water and the inert gases helium, neon and argon, and also the molecules nitrogen and carbon dioxide. Analysis of these results has led to a semi-quantitative comparison between the effect of chirp rate and the atomic and molecular collision partners. The experimental signals have also been compared with those calculated by numerical solution of the coupled Maxwell-Bloch equations. TG11 15 min 4:24 HIGH PRECISION MID-IR SPECTROSCOPY OF NEAR 4.3 WEI-JO TING, PEI-LING LUO,CHIEH-HSING CHUNG, Dept. of Physics, National Tsing Hua University, Hsinchu, Taiwan 30013, R.O.C; HSHAN-CHEN CHEN, Inst. of Photonics Technologies, National Tsing Hua University, Hsinchu, Taiwan 30013, R.O.C; YU-HUNG LIEN, and JOW-TSONG SHY, Dept. of Physics, National Tsing Hua University, Hsinchu, Taiwan 30013, R.O.C. We have observed the sub-Doppler saturation spectrum of the near 4.3 using a mW-level DFG (Difference Frequency Generation) source. The DFG radiation is generated by a 1-W Ti:sapphire laser and a Nd:YAG laser amplified by 10-W fiber amplifier in a 50-mm long PPLN (Periodically Poled Lithium Niobate) crystal. We are able to generate 2 mW DFG power at 4.3 . The Nd:YAG laser is frequency-doubled, and frequency stabilized on one hyperfine transition. The Ti:sapphire laser is locked onto the center of transition and its frequency is measured by an OFC (Optical Frequency Comb). In this talk, we will report our recent measurements on the high J 0001 0000 fundamental band transitions and the hot band 0111 0110 transitions. To increase the signal-to-noise ratio of the observed spectra, the absorption cell in heated to a temperature 8 Æ . 159 TG12 15 min 4:41 OZONE : CRITICAL EVALUATION OF THE STATISTICS OF THE DARK STATE ANALYSES VIA NEW OBSERVATIONS A. BARBE, Groupe de Spectrométrie Moléculaire et Atmosphérique, U.M.R. CNRS 6089, Université de REIMS, Moulin de la Housse, B.P. 1039, 51687 REIMS cedex 2, FRANCE; E. STARIKOVA, LTS, Institute of Atmospheric Optics, 634055 TOMSK, RUSSIA; M.-R. DE BACKER-BARILLY, VL.G. TUYTEREV, ; and Groupe de Spectrométrie Moléculaire et Atmosphérique, U.M.R. CNRS 6089, Université de REIMS, Moulin de la Housse, B.P. 1039, 51687 REIMS cedex 2, FRANCE; A. CAMPARGUE, Groupe de Spectrom étrie Moléculaire et Atmosphérique, U.M.R. CNRS 6089, Université de REIMS, Moulin de la Housse, B.P. 1039, 51687 REIMS cedex 2, FRANCE. The analyses of high resolution infrared spectra of ozone very often require the introduction of perturbing rovibrational states for which no corresponding transitions are observed. It is customary to call these bands (respectively states) dark bands (dark states). These bands have weak dipole transition moments, as in the case of ozone, there is no bands forbidden by the symmetry. In consequence, this denomination depends of the signal/noise ratio of the experimental spectra. Recent progress in the theory and improvements of sensitivity of experiments are continuously achieved, allowing us to assign five B type bands, which were considered as dark in recent previous works. These bands are + , + , + + for O and 2+ + , + for . As a lot of information coming from dark states (band centres, rotational constants) is useful for the Potential Energy Surface (P.E.S) determination, one needs realistic error bars to make consistent comparisons. These new data offer excellent opportunities to compare these error bars (now correctly known) with those previously derived from the dark state fits. This is the aim of this presentation. TG13 15 min 4:58 REAL TIME IN FLIGHT DETECTION OF METHANE, NITROUS OXIDE, CARBON DIOXIDE AND NITRIC OXIDE USING A CHIRPED QC LASER SPECTROMETER K. G. HAY, G. DUXBURY and N. LANGFORD, Department of Physics, SUPA, John Anderson Building, University of Strathclyde, 107 Rottenrow, Glasgow G4 0NG, Scotland,UK. Frequency down-chirped long pulse quantum cascade laser spectrometers have proved to be useful tools for measuring trace levels of atmospheric gases. In this contribution we show that a resolution of ca. 0.005 cm may be achieved using a pulsed laser. We also demonstrate the sensitivity of these instruments via two examples of the use of these spectrometers for in flight measurements of trace concentrations. These comprise two series of low level flights in the small NERC Dornier aircraft over the South Wales peninsula in the UK. The recent results obtained in February 2009 using a three channel instrument designed by Cascade Technologies are compared with those made using our single channel instrument in 2007. a One of the main changes made in the current instrument is the replacement of the fast liquid nitrogen cooled MCT detector used in the earlier flights by an even greater bandwidth, Peltier cooled, MCT detector, which has proved to give better detectivity as well as better resolution. It also eliminates the reliance on liquid nitrogen.The altitudes of the flights ranged from about 500 to 800 m. The gases detected in the original flights were methane, nitrous oxide and water.The wavelength micro-windows chosen for the flight in February 2009 were set to detect nitrous oxide, nitric oxide and carbon dioxide. a K. G. Hay, S. Wright, G. Duxbury and N. Langford App. Phys. B90, 329 2008. 160 TG14 10 min 5:15 REAL-TIME ANALYSIS OF RAMAN SPECTRA FOR TEMPERATURE FIELD CHARACTERIZATION IN AIRCRAFT EXHAUST NOISE STUDIES J. WORMHOUDT, D. D. NELSON, K. ANNEN, Aerodyne Research, Inc., Billerica, MA 01821; R. J. LOCKE, ASRC Aerospace Corporation, Cleveland, OH 44135; and M. WERNET, NASA Glenn Research Center, Cleveland, OH 44135. Raman scattering has long been used as a non-intrusive diagnostic of temperatures in combustion exhaust flows, using a variety of spectral analysis techniques. As part of their ongoing program of experiments to support development of computer codes that calculate exhaust flow fields and predict jet noise, NASA Glenn Research Center is developing a laser Raman diagnostic system that will measure mean temperatures and temperature fluctuations in hot and cold jet flows. We describe a software package, ART (Analysis for Raman Temperatures), that analyzes Raman spectra of air for temperature and density using vibrational or resolved or unresolved rotational bands, presenting results in a variety of real-time displays. Each analysis technique presents its own challenges in obtaining the most precise and accurate values, and we will comment on these issues by exhibiting example spectra of each type. The ART program is closely related to another Aerodyne software package (TDLWintel) which automates the acquisition and analysis of tunable laser absorption spectra. TG15 10 min 5:27 COLLISIONAL EXCITATION OF AUTOMOTIVE FUEL COMPONENTS (ETHANOL AND ISOOCTANE) RACHELLE H. COBB, ALLEN R. WHITE,, Department of Mechanical Engineering, Rose-Hulman Institute of Technology, 5500 Wabash Ave., Terre Haute, IN 47803; REBECCA B. DEVASHER, Department of Chemistry, Rose-Hulman Institute of Technology, 5500 Wabash Ave., Terre Haute, IN 47803. It is possible to excite fuel components indirectly via a 10.6 um CO2 laser. A 9CO2 laser excitation of pure ethanol caused little or no change in absorption in the C-H stretch region. However, the ethanol/isopropanol mixture did show a response proportional to laser excitation. Further studies indicate that excitation of isooctane/isopropanol mixture is also possible via collisional energy transfer between the laser excited isopropanol and isooctane. TG16 ANALYSIS OF URINARY CALCULI USING INFRARED SPECTROSCOPIC IMAGING 15 min 5:39 VALDAS SABLINSKAS, DAIVA LESCIUTE, Dept. of General Physics and Spectroscopy, Faculty of Physics, Vilnius University, Sauletekio av. 9 bl. 3, LT-01222, Vilnius, Lithuania. ; VAIVA HENDRIXSON, Dept. of Physiology, Biochemistry and Laboratory Medicine, Faculty of Medicine, Vilnius University, M. K. Ciurlionio str. 21, LT-03101, Vilnius, Lithuania. Kidney stone disease is a cosmopolitan disease, occurring in both industrialized and developing countries and mainly affecting adults aged 2060 years. The formation of kidney stones is a process that includes many factors. Its primary and contributing pathogenic factors are genetic, nutritional and environmental, but also include personal habits. Information about the chemical structure of kidney stones is of great importance to the treatment of the kidney diseases. The usefulness of such information was first recognized in early 1950s. Analysis of urinary stones by various chemical methods, polarization microscopy, x-ray diffraction, porosity determination, solid phase NMR, and thermo analytical procedures have been widely used. Unfortunately, no one method is sufficient to provide all the clinically useful information about the structure and composition of the stones. Infrared spectroscopy can be considered a relatively new method of kidney stone analysis. It allows to identify any organic or inorganic molecules the constituents of kidney stones. So far this method had never been used to collect information about kidney stone component patterns in Lithuania. Since no epidemiological studies have been performed in this field, the medical treatment of kidney stone disease is empirical and often ineffective in hospitals around the country. The aim of this paper is to present some results of analysis of kidney stones extracted from local patients using FTIR spectroscopical microscopy. 161 TH. MINI-SYMPOSIUM: FIR/THz AIR/SPACE MISSIONS TUESDAY, JUNE 23, 2009 – 1:30 PM Room: 1000 McPHERSON LAB Chair: HOLGER MÜLLER, Universität zu Köln, Köln, Germany TH01 INVITED TALK 30 min 1:30 TERAHERTZ SPECTROSCOPY OF MOLECULES IN THE INTERSTELLAR MEDIUM AND AROUND STARS – SURE BETS AND CHALLENGES KARL M. MENTEN, Max-Planck-Institut f ür Radioastronomie, Auf dem H ügel 69, D-53121 Bonn. In the very near future, powerful new observatories will revolutionize broad band astronomical spectroscopy at THz frequencies. These include the Herschel Space Observatory, the Atacama Large Millimeter Array and, at somewhat lower, GHz, frequencies the Expanded Very Large Array. The latter two, “radio”-style interferometers will allow sub-arcsecond, high spectral resolution imaging with total instantaneous observing bandwidths up to 100 times larger than present day facilities. This will allow comprehensive multi-transition/multi species studies that offer new approaches to a variety of astrophysical/chemical areas all of which are dependent on the availability of extensive laboratory data. To give a few examples: For many interesting sources it will be possible to get a complete astrochemical “fingerprint” in a single observing session with high-quality images of the distributions of the individual species! Targets include the extremely molecule-rich hot molecular cores around protostellar objects and emission from vibrationally excited lines from the innermost circumstellar envelopes of nearby asymptotic branch branch stars which will be imaged with a resolution better than the stellar diameter. Complete, high spectral resolution scans of various keystone objects over the whole 480–1250 and 1410–1920 GHz ranges will be conducted by the Heterodyne Instrument for the Far-Infrared (HIFI) aboard Herschel. These include lines from various important hydride species and, importantly, water vapor that are not observable from the ground. Organic molecules have hundreds of GHz/THz lines. However, due to the generally low abundances and large partition functions of “new” (yet to identified) very complex species, all of these are weak and have to be picked out of a thicket of also weak rotational lines from within relatively low energy vibrationally excited levels from various isotopologues of known species. Here, comprehensive model spectra of all the species known to exist in a source have to be constructed to “weed out” the contaminants. This requires comprehensive laboratory data, which as of now is far from existing. Moreover, Herschel will allow access to types of transitions, e.g., vibrational ones from carbon chain species, for which spectroscopic data has yet to be obtained. I shall give an overview of the challenges and great opportunities of astronomical molecular spectroscopy in the coming years and the crucial role of laboratory spectroscopy. 162 TH02 15 min 2:05 MOLECULAR SPECTROSCOPY AND THE ATACAMA LARGE MILLIMETER/SUBMILLIMETER ARRAY (ALMA) ANTHONY J. REMIJAN, NORTH AMERICAN ALMA SCIENCE CENTER (NAASC), National Radio Astronomy Observatory, 520 Edgemont Road, Charlottesville, VA 22903. The next generation of powerful millimeter/submillimeter (e.g. ALMA, LMT & Herschel) and radio (GBT, NRAO’s our most over-subscribed telescope, & eVLA) observatories require extensive resources to help identify and analyse spectral line transitions. The Atacama Large Millimeter/submillimeter Array (ALMA), an international astronomy facility, is a partnership of East Asia, Europe and North America in cooperation with the Republic of Chile. The North American ALMA Science Center (NAASC) in Charlottesville, Virginia, is responsible for supporting the science use of ALMA by the North American astronomical community (the USA via the NRAO and Canada via the National Research Council of Canada) and for research and development activities in support of future upgrades of ALMA. In this presentation, I will first present the current state of the ALMA project and the NAASC and second, the steps taken by the NA ALMA partners to address the spectroscopic needs of the observatory including project ”Splatalogue”. Finally, I will discuss the additional plans of the NAASC to provide tools for the analysis of spectroscopic products of the observatory, such as spectral line data cubes. TH03 THE HERSCHEL SPACE OBSERVATORY, OPENING THE FAR INFRARED 15 min 2:22 JOHN C. PEARSON, JET PROPULSION LABORATORY, CALIFORNIA INSTITUTE OF TECHNOLOGY, 4800 OAK GROVE DR., PASADENA, CA 91109. The Herschel Space Observatory (Herschel) is a multi user observatory operated by the European Space Agency with a significant NASA contribution. Herschel features a passively cooled 3.5 meter telescope expected to operate near 78 Kelvin and three cryogenic instruments covering the 670 to 57 m spectral region. The mission life time, determined by the consumption of 2500 liters of liquid helium, is expected to be at least 3.5 years with at least 3 years of operational lifetime in an L2 orbit. The three payload instruments are the Spectral and Photometric Imaging Receiver (SPIRE), Photodetector Array Camera and Spectrometer (PACS), and the Heterodyne Instrument for Far Infrared (HIFI). SPIRE covers 200-670 m and is a three band bolometer based photometer and a two band imaging Martin-Puplett FTS with a spectral resolution of up to 600. PACS covers 57-200 m and is a three band bolometer based photometer and a grating slit spectrometer illuminating photoconductor arrays in two bands with a resolution of up to 5000. HIFI covers 480-1272 GHz and 14401910 GHz and is a series of seven dual polarization heterodyne receivers with a spectral resolution up to . The observatory performance, selected science program and upcoming opportunities will be discussed. TH04 THE STRATOSPHERIC OBSERVATORY FOR INFRARED ASTRONOMY (SOFIA) 15 min 2:39 R. D. GEHRZ, Department of Astronomy, University of Minnesota, 116 Church Street, S. E., Minneapolis, MN 55455; E. E. BECKLIN, Universities Space Research Association, NASA Ames Research Center, MS 211-3, Moffett Field, CA 94035. SOFIA is a 2.5-meter infrared airborne telescope in a Boeing 747-SP that will begin will begin science flights in mid-2009. Flying in the stratosphere at altitudes as high as 45,000 feet, SOFIA will be used to conduct spectroscopic and imaging observations throughout the infrared and sub-mm region with an average transmission of greater than 80 percent. The SOFIA first-generation instrument complement includes broadband imagers, moderate resolution spectrographs capable of resolving broad features due to dust and large molecules, and high resolution spectrometers suitable for kinematic studies of molecular and atomic gas lines at km/s resolution. The characteristics and status of the observatory and its instrumentation will be briefly reviewed. SOFIA‘s operations schedule and opportunities for observers and instrument developers will be described. 163 TH05 15 min 2:56 INFRARED SPECTROSCOPY OF ASTROPHYSICAL GAS, GRAINS, AND ICES WITH THE STRATOSPHERIC OBSERVATORY FOR INFRARED ASTRONOMY (SOFIA) R. D. GEHRZ, Department of Astronomy, University of Minnesota, 116 Church Street, S. E., Minneapolis, MN 55455; E. E. BECKLIN, Universities Space Research Association, NASA Ames Research Center, MS 211-3, Moffett Field, CA 94035. The joint U.S. and German Stratospheric Observatory for Infrared Astronomy (SOFIA) will be a premier facility for studying the physics and chemistry of the stellar evolution process for many decades. SOFIA spectroscopic science applications will be discussed, with special emphasis on investigations related to infrared spectroscopy of astrophysical gas, grains, and ices. Examples will be given of spectroscopic studies of the interstellar medium, protostars, obscured sources in molecular cloud cores, circumstellar disks around young stellar objects, remnants of nova and supernova explosions, and winds of evolved stellar systems. TH06 15 min 3:13 TERAHERTZ SPECTROSCOPY AND GLOBAL ANALYSIS OF H O SHANSHAN YU, BRIAN J. DROUIN, JOHN C. PEARSON AND HERBERT M. PICKETT, Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109. Eight ground state inversion transitions of H O in the 0.9-1.6 THz region have been measured using the frequency multiplier submillimeter spectrometer (FMSS) at JPL. The accuracy of these measurements is estimated to be 300 kHz. The ions were generated in a DC discharge through a gas mixture of a few mTorr of H and 30 mTorr of H O. A multistate analysis was carried out for H O , which includes the lines observed in this work, previous submillimeter and terahertz inversion transitions in the ground state, and previous infrared data on all the four vibrational fundamental bands. Accurate molecular parameters were obtained with taking into account the strong Coriolis interaction between the symmetric OH stretching mode and the doubly degenerate asymmetric OH stretching mode . Frequency predictions, particularly for high-& transitions in the ground state and in the and fundamental bands, have been greatly improved by including in our analysis 200 more high-& transitions, which were excluded in previous analyses. The more precise measurements and new predictions reported here will support the analysis of astronomical observations by the future high resolution spectroscopy telescopes such as Herschel, SOFIA, and ALMA. TH07 15 min 3:30 ACCURATE POTENTIAL ENERGY SURFACE, ROVIBRATIONAL ENERGY LEVELS, AND TRANSITIONS OF AMMONIA ISOTOPOLOGUES: NH , NH , ND and NT XINCHUAN HUANG, MS 245-6, NASA Ames Research Center, Moffett Field, CA, 94035; DAVID W. SCHWENKE, MS T27B-1, NASA Ames Research Center, Moffett Field, CA, 94035; TIMOTHY J. LEE, MS 245-1, NASA Ames Research Center, Moffett Field, CA, 94035. A further refined, global potential energy surface (PES) is computed for the symmetry isotopologues of ammonia, including NH , NH , ND and NT . The refinement procedure was similar to that used in our previously reported PESa , but now extends to higher & energy levels and other isotopologues. Both the diagonal Born-Oppenheimer correction and the non-adiabatic correction were included. & rovibrational energy levels and transition frequencies of NH computed on this PES are in excellent agreement with HITRAN data. Statistics on nearly 4100 transitions and more than 1000 energy levels demonstrate the accuracy achieved by the state-of-the-art ”Best Theory + Experiment” strategy. Most transition frequencies are of % % cm accuracy. Similar accuracy has been found on NH & rovibrational energy levels. Several transitions and energy levels in HITRAN have been identified as unreliable or suspicious, and some have been re-assigned. For ND and NT , & calculations have been performed. Agreement for pure rotation-inversion transitions is nearly perfect, with more reliable energy levels presented. On the other hand, our & results suggest a re-analysis on the ND band origin is needed. Finally, we will discuss possible future refinements leading to an even better final PES for Ammonia. a X. Huang, D.W. Schwenke, and T.J. Lee, J. Chem. Phys. 129, 214304 (2008). 164 Intermission TH08 15 min 4:00 MEASUREMENT AND ANALYSIS OF ATMOSPHERICALLY BROADENED LINEWIDTHS AND LINESHAPES IN THE MILLIMETER SPECTRAL REGION COREY CASTO and FRANK C. DE LUCIA, Department of Physics, The Ohio State University, Columbus, OH 43210-1106. Millimeter and sub-millimeter spectroscopy ordinarily takes advantage of the sharpness of near Doppler limited linewidths to separate molecular effects from instrumental effects. As a result, spectroscopically broader effects that manifest themselves at atmospheric pressures are more difficult to study experimentally. We have previously described an approach to the study of these phenomena, FASSST Cavity Ring Down spectroscopy. We had observed ozone spectra at room temperature where ozone reacts with materials in our cavity making it difficult to compare spectra with theory. In this talk, we will describe room temperature spectra of sulfur dioxide and cold temperature spectra of ozone and compare them with theoretical models and parameters based on low pressure measurements. TH09 15 min 4:17 PRESSURE BROADENING OF SEVERAL TERAHERTZ TRANSITIONS OF WATER FROM 20K TO 200K MICHAEL J. DICK, BRIAN J. DROUIN and JOHN C. PEARSON, Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California 91109. The pressure broadening of the 0 to 1 , 1 to 2 , 3 to 3 , 2 to 3 and 3 to 3 transitions of water by hydrogen and helium has been investigated using the collisional cooling technique. This technique has allowed the broadening to be examined over the temperature range of 20K to 200K, far below the freezing point of water. The results of the investigation show a general trend of two distinct regions of broadening for each rotational line. Above 50K, the temperature dependence of the broadening follows the expected power law behavior. Below 50K, the broadening decreases very rapidly with temperature. This behavior is similar to that observed in a recent study of the pressure broadening of the 556 GHz line of water completed in our lab. However, this behavior is in sharp contrast to that predicted by previous theoretical calculations. We will present the results of our current investigation. This will include a discussion comparing the current study with the results of the previous experimental and theoretical work. The pressure broadening is a window into the collisional excitation and the implications of our results for the interpretation of water spectra in the interstellar medium will be discussed. 165 TH10 ASSIGNMENT AND ANALYSIS OF LOW-BARRIER ASYMMETRIC TOPS WITH SPFIT/SPCAT 15 min 4:34 BRIAN J. DROUIN, JOHN C. PEARSON, Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109-8099. The interstellar medium contains a cornucopia of organic molecules. Unfortunately, a number of these molecules have highly complex spectra that require great efforts to achieve the comprehensive spectral understanding that might allay the confusion presented by unidentifiable features expected from next-generation submillimeter telescopes. Pickett’s program suite SPFIT/SPCAT was developed to nurture the need for a cohesive and comprehensive database and, as such, has become the cornerstone of the two most utilized astrophysical molecular databases (JPL and CDMS ). Over the last several years this highly versatile fitting program has undergone significant modification (Pickett developed a front-end program known as IAMCALC) in order to accommodate the generic hindered rotor. Two years ago we laid out the plan for comprehensive assignments of acetaldehyde, which had been systematically studied up to 0.6 THz with the Reduced axis system internal rotation code (Belgi) , and now this plan is essentially complete with assignments of the ground and first two torsional states accomplished through 1.6 THz. The ground and first torsional state are fit to near experimental uncertainty. The application of this approach to methyl formate, for which a similar data set has been compiled , will also be discussed. Pickett HM. J. Mol. Spec. 1991; 148(2): 371-377. Pickett HM, et al., J. Quant. Spectrosc. Radiat. Transfer. 1998; 60(5), 883-890. Müller HSP, Schlöder F, Stutzki J, Winnewisser G. J. Mol. Struct. 2005; 742: 215-227. Kleiner, Lovas & Godefroid, J. Phys. Chem. Ref. Data. 1996, Vol 25(4). Carvajal M, et al., J. Mol. Spec. 2007; 246(2), 158-166. TH11 MILLIMETER WAVE AND TERAHERTZ SPECTRA OF C-13 METHANOL 15 min 4:51 LI-HONG XU, RONALD M. LEES, Department of Physics and Centre for Laser, Atomic, and Molecular Sciences, University of New Brunswick, Saint John, NB E2L 4L5, Canada; HOLGER S. P. M ÜLLER, CHRISTIAN P. ENDRES, FRANK LEWEN, STEPHAN SCHLEMMER, I. Physikalisches Institut, Universitt zu Köln, 50937 K öln, Germany; KARL M. MENTEN, Max-Planck-Institut f ür Radioastronomie, 53121 Bonn, Germany. Methanol is a very ubiquitous molecule in space. A previous combined analysis of microwave and millimeter wave spectra of C-13 methanol together with Fourier transform far-infrared spectra was limited to the first two torsional states (i.e. 1 and 1 for & values up to 20). a We have recently carried out new millimeter and terahertz measurements for CH OH on several different spectrometers in the Cologne laboratory to overcome the limits in frequency and quantum number coverage. The new measurements have been carried out in the frequency windows 34–70 GHz, 75–120 GHz, 240–340 GHz, 370–500 GHz and 1.12–1.35 THz. With the new data, we are extending our previous global treatment to include the first three torsional states (i.e. 1 , 1 and 2 for & values up to 30). We hope to provide the radio astronomical community with a C-13 methanol database that will have been improved substantially compared to the existing one. b The new database will be available in the Cologne Database for Molecular Spectroscopy, CDMS c , in support of present and future astronomical studies associated with the launch of HIFI (Heterodyne Instrument for the Far-Infrared) on board the Herschel Space Observatory, the flying of SOFIA (Stratospheric Observatory For Infrared Astronomy) and the commissioning of ALMA (Atacama Large Millimeter/Submillimeter Array). a Li-Hong Xu, M. S. Walsh, R. M. Lees, 1996, J. Mol. Spectrosc. 179, 269-281. Xu, F. J. Lovas, 1997, J. Phys. Chem. Ref. Data, 26, 17-156; also available in the CDMS, see . c H. S. P. Müller, S. Thorwirth, D. A. Roth, G. Winnewisser, 2001, Astron. Astrophys. 370, L49-L52; H. S. P. Müller, F. Schlöder, J. Stutzki, G. Winnewisser, 2005 J. Mol. Struct. 742, 215-227; web-page: http://www.astro.uni-koeln.de/cdms/. b Li-Hong 166 TH12 15 min 5:08 GAS CELL OBSERVATIONS OF METHANOL FROM 0.6 TO 1.9 THZ USING THE HERSCHEL SPACE OBSERVATORY HIFI INSTRUMENT RONAN D. HIGGINS, Department of Experimental Physics, National University of Ireland, Maynooth, Co. Kildare, Ireland; JOHN C. PEARSON, Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA; STEVE D. LORD, NHSC, California Institute of Technology, Pasadena, CA 91125, USA; DAVID TEYSSIER, Herschel Science Centre, European Space Astronomy Centre (ESAC), 28691 Villanueva de la Ca ñada, Madrid, Spain. The Herschel HIFI instrument, in its ground testing, collected over 6000 spectra of methanol (with natural terrestrial isotopic abundance). These data were gathered primarily to validate the instrument’s spectroscopic functionality and proper operation. They have a secondary benefit of increasing the database of methanol lines. Furthermore, the data has enormous and largely untapped potential for a fundamental spectroscopic investigation. We present the analysis of this broad range of methanol spectra and detail the instrument effects seen. Additionally we detail the new insight into the torsional states and self-broadening characteristics of methanol. TH13 THE SUBMILLIMETER SPECTRUM OF THE GROUND TORSIONAL STATE OF CH DOH 15 min 5:25 JOHN C. PEARSON, CAROLYN S. BRAUER, SHANSHAN YU, and BRIAN J. DROUIN, JET PROPULSION LABORATORY, CALIFORNIA INSTITUTE OF TECHNOLOGY, 4800 OAK GROVE DR., PASADENA, CA 91109. Methanol and its isotopologues are well known tracers of gas grain chemistry with deuteration of the methyl group being energetically favorable in very cold environments on grain surfaces. In order to study the early evolution of star forming cores, constrain grain chemistry, and to develop a methodology for addressing the completely asymmetric internal rotation problem, the spectrum of CH DOH in its ground torsional state has been investigated to 1.6 THz. The study has facilitated the assignment of a complete ladder of highly interconnected energy levels in the 0 , 0 and sub-states. The ground state spectrum of completely asymmetric CH DOH with symmetry has been assigned to & 8 and ' in each substate, respectively. This ' range facilitates coverage of one full period of (' and provides some valuable insight into the completely asymmetric internal rotation problem. The energy level structure also provide a unique opportunity for a direct comparison to normal methanol with its internal rotation. The spectral features, analysis and energy level structure will be discussed and compared to that of normal methanol. 167 TI. ATMOSPHERIC SPECIES TUESDAY, JUNE 23, 2009 – 1:30 PM Room: 1015 McPHERSON LAB Chair: MARK MARSHALL, Amherst College, Amherst, Massachusetts TI01 15 min 1:30 ABSORPTION SPECTRUM OF 2-NITROOXYBUTYL PEROXY RADICAL The NATHAN EDDINGSAAS, KANA TAKEMATSU, and MITCHIO OKUMURA, Arthur Amos Noyes Laboratory of Chemical Physics, California Institute of Technology, Pasadena, California 91125. The nitrate radical is an important atmospheric oxidant in the nighttime sky. Nitrate radicals react by addition to alkenes, and in the presence of oxygen form nitrooxyalkyl peroxy radicals. The peroxy radical formed from the reaction of 2-butene, electronic absorption specnitrate radical, and oxygen was detected by cavity ringdown spectroscopy (CRDS) via its electronic transition is a bound-bound transition with enough structure to distinguish between different trum. The peroxy radicals as well as different conformers of the same peroxy radical. Two conformers of the nitrooxybutyl peroxy radical have been observed; the absorption features are red shifted from the same absorption features of sec-butyl peroxy radical. Calculations on the structure of nitrooxyalkyl peroxy radicals and general trends of the position of the absorption transitions have also been performed and compared to those of unsubstituted peroxy radicals. TI02 THE DISSOCIATION ENERGY OF THE HOOO RADICAL 15 min 1:47 M.E. VARNER, J. VÁZQUEZ, M.E. HARDING, J.F. STANTON, Department of Chemistry, The University of Texas at Austin, TX; J. GAUSS, Institut f ür Physikalische Chemie, Universität Mainz, Germany. The dissociation of the hydrogen trioxyl radical (HOOO) to OH and O has been studied theoretically using coupled cluster methods. The calculated dissociation energy for the trans-HOOO isomer is 2.4 kcal/mol including zero-point corrections. The minimum energy path to dissociation has been explored and an exit barrier has been revealed, thereby rationalizing the apparent disagreement between theory and experiment on the magnitude of the bond energy. TI03 15 min 2:04 INFRARED ABSORPTION OF GASEOUS -CLCOOH AND -CLCOOH RECORDED WITH A STEP-SCAN FOURIER-TRANSFORM SPECTROMETER YUAN-PERN LEE AND LI-KANG CHU, Department of Applied Chemistry and Institute of Molecular Science, National Chiao Tung University, Hsinchu 30010, Taiwan and Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 10617, Taiwan. Two conformers of ClCOOH were produced upon irradiation at 355 nm of a gaseous flowing mixture of Cl , HCOOH, and N . A step-scan Fourier-transform infrared spectrometer coupled with a multipass absorption cell was utilized to monitor the transient spectra of ClCOOH. Absorption bands with origins at 1808.0 and 1328.5 cm are attributed to the C=O stretching and COH bending modes of -ClCOOH, respectively; those at 1883.0 and 1284.9 cm are assigned as the C=O stretching and COH bending modes of -ClCOOH, respectively. These observed vibrational wavenumbers agree with corresponding values for -ClCOOH and -ClCOOH predicted with B3LYP/aug-cc-pVTZ density-functional theory and the observed rotational contours agree satisfactorily with simulated bands based on predicted rotational parameters. The observed relative intensities indicate that -ClCOOH is more stable than -ClCOOH by 3 kJ mol . A simple kinetic model is employed to account for the production and decay of ClCOOH. 168 TI04 ANALYSIS OF THE BAND OF THE FCO RADICAL: PRELIMINARY RESULTS 15 min 2:21 A. PERRIN, Laboratoire Inter Universitaire des Systemes Atmosph ériques, CNRS, Universités Paris 12 et 7, 61 Av du Général de Gaulle, 94010 Créteil Cedex France; M. STŘIŽÍK, VŠB-Technical University of Ostrava, Faculty of Safety Engineering, Lumı́rova 13, CZ-70030, Ostrava 3 - V ýškovice, Czech Republic, Institute of Thermomechanics, v.v.i., Academy of Sciences of the Czech Republic, Dolejškova 5, CZ-18200 Prague 8, Czech Republic; H. BECKERS, H. WILLNER, Inorg. Chemistry, University of Wuppertal, D-42119 Wuppertal, GERMANY; Z.ZELINGER, P.PRACNA, J. Heyrovský Institute of Physical Chemistry, Academy of Sciences of the Czech Republic, Dolejškova 3, CZ-18223 Prague 8, Czech Republic; V. NEVRL Ý, E. GRIGOROVÁ, VŠB-Technical University of Ostrava, Faculty of Safety Engineering, Lumı́rova 13, CZ-70030, Ostrava 3 - Výškovice, Czech Republic, Institute of Thermomechanics, v.v.i, Academy of Sciences of the Czech Republic, Dolejškova 5, CZ-18200 Prague 8, Czech Republic.. The unique fluoroformyloxyl radical (FCO ) is assumed to participate in atmospheric processes such as the degradation of hydrofluorocarbons that have been considered as chlorofluorocarbon substitutes. Despite this atmospheric interest, the molecular and spectroscopic properties of FCO have not yet sufficiently been explored. The high resolution FT IR gas phase spectrum of the fluoroformyloxyl (FCO ) radical was recorded in the 650 - 1500 cm spectral range at the University of Wuppertal. Using this spectrum and the ground state parameters achieved recently a we carried out the first high resolution study of the -type band (C-F stretching mode) centered at 970.209 cm . The analysis was difficult because the band is congested. In addition the spin doublets are difficult to identify except for high K values. However, we could take advantage of the fact that only K =odd values are observable for symmetry reasons. The line position calculation accounts for the spin rotation doubling and for the Fermi-type resonances linking the 2 and 5 spin rotation energy levels. a Kolesnikova, Varga, Beckers, Simeckova, Zelinger, Nova Striteska, Kania, Willner, and Urban, J. Chem Phys 128, 224 (2008) TI05 15 min 2:38 CONFORMATIONAL ANALYSIS OF 1-ALKENE SECONDARY OZONIDES BY MEANS OF MATRIX ISOLATION FTIR SPECTROSCOPY VALDAS SABLINSKAS, SIMONA STRAZDAITE, JUSTINAS CEPONKUS, Dept. of General Physics and Spectroscopy, Faculty of Physics, Vilnius University, Sauletekio av. 9 bl. 3, LT-01222, Vilnius, Lithuania. An ability of ozone to break double C=C bond in olefins is known for more than five decades. Understanding of those reactions is very important in atmospheric chemistry. During different steps of the reaction the primary ozonide (POZ), carbonyl oxide (COX) and the secondary ozonide (SOZ) are formed. Fate of the reaction depends on many parameters such as type of radical, conformation of alkene, temperature of the reaction and environmental effects. Despite of numerous studies of the reaction by different spectroscopic techniques the precise mechanism of the reaction is still unknown. It is experimentally observed that the SOZ is more stable than POZ. Stability of the SOZ depends on the size and configuration of the radical. Unfortunately, it is not much known about the spatial structures of the SOZes. The aim of this study is to define the geometrical structures and stability of the different conformers of the 1-butene and 1-heptene secondary ozonides by combined analysis of the matrix isolation FTIR spectral data with the results of Density Functional Theory (DFT) calculations. Intermission 169 TI06 15 min 3:15 TEMPERATURE DEPENDENCE OF THE VIBRATIONAL RELAXATION OF OH( = 1, 2) BY O, O , AND CO C. ROMANESCU, H. TIMMERS, K. S. KALOGERAKIS, G. P. SMITH, and R. A. COPELAND, SRI International, Molecular Physics Laboratory, 333 Ravenswood Ave., Menlo Park, CA 94025. The hydroxyl radical is a key reactant in the energy budget of the atmospheres of terrestrial planets. In the Earth s upper atmosphere, OH( 9) is formed by the H + O reaction. Recently, OH( = 1 and 2) emission has been observed in the atmosphere of Venus. a The magnitude of this emission is controlled by the competition between radiative decay and vibrational relaxation by the most abundant collider, CO . The data needed to model the emission rates of vibrationally excited OH radical include the vibrational quenching rates at temperatures relevant to the planetary atmospheres and the branching ratio between single- and multi- quantum relaxation steps. The latter parameter plays a crucial role in establishing the emission rates, as demonstrated by recent model calculations. b Given the importance of rate constants and branching ratios for understanding the behavior of atmospheric OH on both Earth and Venus, we applied a two-laser approach to measure the rate constants for the vibrational relaxation of OH( = 1, 2) by O-atoms, O , and CO . In these experiments, ozone is almost completely photolyzed at 248 nm and most of the resulting O( ) atoms quenched to O( " ) by collisions with N and CO . A small fraction of O( ) reacts with H O, forming OH( 2). The temporal evolutions of OH( = 1, 2) are measured using laser induced fluorescence and kinetic simulations are used to extract the rate constants and the relaxation branching ratios. Experiments were performed at temperatures between 210 and 300 K. We find that the collisional removal rate constants for OH( = 2) increase as the temperature decreases. The CO branching ratio indicates that most of OH( = 2) relaxes to OH( = 1) following collisions with CO , i.e., the cascading removal pathway is predominant. This work was supported by NASA Geospace Science and Planetary Atmospheres Programs. The participation of H. Timmers was supported by an NSF Research Experiences for Undergraduates (REU) Program. a G. b A. Piccioni et al., Astronomy & Astrophysics, 483, L29 (2008) G. Garcia-Muñoz et al., Icarus, 176,75 (2005); X. Zhu and J. H. Yee, Icarus, 189, 136 (2007) TI07 15 min 3:32 EXPERIMENTAL AND THEORETICAL INVESTIGATIONS OF HBr+He ROTATIONAL ENERGY TRANSFER M. H. KABIR, I. O. ANTONOV, J. M. MERRITT, and M. C. HEAVEN, Department of Chemistry, Emory University, Atlanta, GA 30322. Optically pumped HBr lasers are currently being investigated to evaluate their potential for high-energy laser applications. Vibrational cascade lasing from molecular HBr at wavelengths near 4-m has been demonstrated when the 3-0 vibrational overtone was excited by a Nd:YAG laser (Kletecka et al. IEEE J. Quant. Electron. 40, 1471 (2004)). Lasing was observed on various rotational lines of the 3-2 and 2-1 bands. For computational modeling and optimization of the HBr laser, stateto-state rotational energy transfer rate constants are needed for HBr+HBr and HBr+He collisions. The present work is focused on the latter. Rotational energy transfer in HBr+He collisions was investigated using an ionization-detected pump-probe double resonance technique at ambient temperature. Rotational state selective excitation of 1 for & was achieved using a pulsed infrared OPO/OPA system, and the time evolution of HBr (1 , & ) was monitored using 2+1 resonantly enhanced multiphoton ionization (REMPI) spectroscopy via the g -X (0-1) band. The experimental data was simulated by fitting to numerical solutions of a set of coupled differential equations describing the full relaxation processes. State-tostate rate constant matrices were generated using fitting and scaling laws. State-to-state rotational transfer rate constants were also calculated using a HBr+He potential energy surface (obtained using the CCSD(T) level of theory) and quantum scattering calculations. Comparisons of experimental and theoretical results will be presented. 170 TI08 15 min 3:49 THE ATMOSPHERIC CHEMISTRY EXPERIMENT, ACE: ORGANIC MOLECULES FROM ORBIT J. J. HARRISON, G. GONZALEZ ABAD, N. ALLEN, P. F. BERNATH, Department of Chemistry, University of York, Heslington, York, YO10 5DD, UK; and C. BOONE, Department of Chemistry, University of Waterloo, Waterloo, ON, N2L 3G1, Canada. Volatile organic compounds (VOCs) are responsible for air pollution. In recent years it has become possible to detect tropospheric VOCs using satellite instruments such as the Atmospheric Chemistry Experiment Fourier transform spectrometer (ACE-FTS). The ACE-FTS is a high resolution (0.02 cm ) instrument covering the 750-4400 cm spectral range in solar occultation mode. ACE was launched by NASA in August 2003 and the FTS continues to operate without any degradation in performance. The primary ACE mission goal is the study of ozone chemistry in the stratosphere although it is making a wide range of other measurements. The partial list of VOCs retrieved from ACE-FTS spectra include methane, methanol, formaldehyde, ethane, ethene and ethyne (see http://www.ace.uwaterloo.ca for a complete list of species and reprints of published papers). In this talk, new global retrievals for formic acid will be presented. The ACE-FTS records spectra in the 3 micron region, which is particularly suitable for the retrieval of hydrocarbons. Methane and ethane are very strong in the 3 micron region, however the existing line parameters are not satisfactory. New high resolution laboratory spectra of ethane have therefore been recorded for the range of temperatures and pressures needed for atmospheric retrievals. Preliminary ethane retrievals will be presented using the laboratory spectra in the form of cross sections, rather than the existing HITRAN line parameters used previously. TI09 GLOBAL METHYL CHLORIDE MEASUREMENTS FROM THE ACE-FTS INSTRUMENT 15 min 4:06 NATALIE WEIGUM, CLARE McELCHERAN, KALEY A. WALKER, JEFFREY R. TAYLOR, Department of Physics, University of Toronto, Toronto, Ontario, Canada M5S 1A7; CHRIS BOONE, PETER F. BERNATH, Department of Chemistry, University of Waterloo, Waterloo, Ontario, Canada N2L 3G1; GEOFFREY C. TOON, GLORIA MANNEY, Jet Propulsion Laboratory, Pasadena, CA 91109, USA; SUSAN STRAHAN, BRYAN DUNCAN, YASUKO YOSHIDA, Goddard Earth Science and Technology Center, University of Maryland, Baltimore County, Baltimore, MD 21250, USA; and YUAHNG WANG, School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, GA USA. One of the most abundant chlorine-containing molecules in the atmosphere is methyl chloride; a species whose sources are almost entirely natural. The most common sources of methyl chloride are tropical plants, senescent or dead leaves and biomass burning. As the impacts of the Montreal Protocol and its subsequent amendments are becoming apparent in the reduction of chlorofluorocarbons in the atmosphere, naturally-produced methyl chloride is playing an increasingly significant role in the atmospheric ozone budget. While much is known about the concentration of methyl chloride at ground level, there are relatively few measurements of its altitude distribution. Solar occultation profiles from the Atmospheric Chemistry Experiment (ACE) satellite mission have been used to produce the first study of the global distribution of methyl chloride in the upper troposphere and stratosphere. Measurements from the infrared Fourier transform spectrometer (ACE-FTS) on board ACE, collected over three years from February 2004 to March 2007, were used in the analysis. These results were compared with results from the MkIV balloon-borne Fourier transform spectrometer, the Global Modelling Initiatives (GMI) combination troposphere and stratosphere model and the GEOS-Chem troposphere model. This paper will discuss the challenges of retrieving methyl chloride from atmospheric spectra. Also, it will discuss the differences between the global methyl chloride distribution as determined from the ACE-FTS and the MkIV FTIR measurements and the GMI and GEOS-Chem models. 171 TI10 15 min 4:23 ABSOLUTE CHEMICAL ANALYSIS OF COMPLEX MIXTURES IN THE SUBMILLIMETER/TERAHERTZ. CHRISTOPHER F. NEESE, IVAN R. MEDVEDEV AND FRANK C. DE LUCIA, Department of Physics, 191 W. Woodruff Ave., Ohio State University, Columbus, OH 43210 USA; GRANT M. PLUMMER, Enthalpy Analytical, Inc., 2202 Ellis Rd., Durham, NC 27703 USA. There has been a resurgence of interest in spectroscopic sensors. Much of this has been driven by increases in performance made possible by advances in lasers and laser systems and the significant applications in medicine, environmental monitoring, and national security that these performance enhancements make possible. Similar increases in performance have occurred in sub-millimeter/THz solid state technology, allowing the development of SMM/THz sensors. In the SMM/THz the rotational fingerprints of small static gas samples provide complexly redundant signatures, resolvable for even moderately large molecules because of the small Doppler limit. These fingerprints, combined with the 8 resolvable spectral channels and 8 distinctly measureable frequencies of cw SMM/THz systems lead to ‘absolute’ specificity, even in complex mixtures. Additionally, clutter from common atmospheric gases is minimal. Interferents such as water, carbon dioxide, and methane either have no rotational spectra, or very sparse spectra in the SMM/THz. Details of the quantitative analyses of mixtures will be provided. TI11 SUB-MILLIMETER/THZ SPECTROSCOPY AT THE CONGESTION LIMIT 15 min 4:40 DAVID L. GRAFF, CHRISTOPHER F. NEESE, IVAN R. MEDVEDEV AND FRANK C. DE LUCIA, The Ohio State University, Department of Physics, Columbus, Ohio 43210. Sub-millimeter/THz spectroscopy has long been viewed as a promising technique for chemical analysis given its high information content. For line-widths of 0.6 MHz, there exist 100,000 resolution elements in 60 GHz of spectral space. However, the analysis of large and complex molecules requires the identification of molecules with small rotational constants and/or many low energy vibrational and torsional states. This leads to spectra characterized by high line densities and large partition functions, potentially populating nearly every resolution element with weak lines. Here we report on a study of spectral congestion and will compare data and information taken from high resolution techniques that depend upon the narrow line-widths of individual lines for detection, modulation schemes based on the near universality of strong Stark modulation in large molecules at high & , and absolute absorption measurements based on cavities. 172 TI12 15 min 4:57 THE WATER-VAPOR CONTINUUM ABSORPTION IN THE MID-INFRARED WINDOWS AT TEMPERATURES FROM 311 K TO 363 K Yu. I. BARANOV, AND W. J. LAFFERTY, Optical Technology Division, NIST, Gaithersburg, MD 208998441, USA. The water-vapor continuum absorption in the mid-infrared 10 m and 4 m atmospheric windows plays an important role in the radiative balance of the Earth. We have derived the continuum absorption coefficients from spectra recorded at NIST with a resolution of 0.1 over a wide range of pressures from 2.8 kPa (21 torr) to 15.1 kPa (113 torr) and temperatures from 311 K to 363 K with path lengths ranging from 74 to 116 m. These measurements were performed with a BOMEM DA3-002 FTIR spectrometer with a 2 m base multi-pass cell. The spectral range was from 800 to 3500 . We have published the results obtained in the 10 m region recently a . At the conditions given above, the continuum absorption in the higher frequency atmospheric window is quite detectable reaching as high as 4%. In order to avoid mistakes caused by the non-linear behavior of a MCT detector we later recorded an additional set of spectra with a highly-linear InSb detector. Both sets of spectra provide absorption coefficients coinciding within error bars. Our results around 5 m are in good agreement with those obtained from the widely used MT-CKD continuum model b . However, at shorter wave lengths, the values diverge dramatically increasing up to one order of magnitude at the center of the window. Despite the comparatively large uncertainties of our data, comparison with all other available results leads us to the conclusion that the MT-CKD model greatly underestimates the self-broadened continuum over the 4 m atmospheric window. We have also extended our measurements to lower frequencies with the use of KRS-5 cell windows. The current spectral range is down to 600 . a Yu. b S. I. Baranov, W. J. Lafferty, Q. Ma, R. H. Tipping, JQSRT 109, 2291, (2008) A. Clough, F. X. Kneizys, and R. W. Davies, Atmos. Res. 23, 229, (1989) 173 TJ. ELECTRONIC TUESDAY, JUNE 23, 2009 – 1:30 PM Room: 2015 McPHERSON LAB Chair: DENNIS CLOUTHIER, University of Kentucky, Lexington, Kentucky TJ01 15 min 1:30 HIGH-RESOLUTION SPECTROSCOPY OF p RYDBERG STATES OF He : 1. RYDBERG-STATE-RESOLVED THRESHOLD IONIZATION SPECTRA OF METASTABLE He JINJUN LIU, DANIEL SPRECHER, MATTHIAS RAUNHARDT, MARTIN SCH ÄFER, and FRÉDÉRIC MERKT, ETH Zürich, Laboratorium f ür Physikalische Chemie, Wolfgang-Pauli-Strasse 10, 8093 Z ürich, Switzerland. A supersonic beam of metastable He a molecules was generated using a pulsed discharge at the exit of a pulsed valve prior to the gas expansion into vacuum. a Transitions to high p Rydberg states were recorded using photoionization and Rydberg-state-resolved threshold ionization spectroscopy. b Overview scans at moderate resolution (0.3 cm ) were obtained with ionization fields ranging from 1.3 to 133 V/cm, lowering the ionization thresholds by 5.5 and 55 cm , respectively. Using a solid-state UV laser system c with a 20 MHz bandwidth, high-resolution spectra of Rydberg series with up to 150 and with resolved fine structure of the initial He a ( ) state were recorded. The assignment of the observed Rydberg states is based on multichannel quantum defect theory calculations from a recent study of pulsed-fieldionization zero-kinetic-energy (PFI-ZEKE) photoelectron and photoionization spectra of He (see following talk). The extrapolation of the observed Rydberg series to their limits enabled the determination of the ionization energy of the a state and the rotational structure of the He ion with a precision of better than 20 MHz. a M. Raunhardt, M. Schäfer, N. Vanhaecke, F. Merkt, J. Chem. Phys. 128, 164310 (2008). Seiler, U. Hollenstein, G. M. Greetham, F. Merkt, Chem. Phys. Lett. 346, 201 (2001). c R. Seiler, Th. A. Paul, M. Andrist, F. Merkt, Rev. Sci. Instr. 76, 103103 (2005). b R. TJ02 15 min 1:47 HIGH-RESOLUTION SPECTROSCOPY OF p RYDBERG STATES OF He : 2. AUTOIONIZATION DYNAMICS AND MQDT CALCULATIONS MARTIN SCHÄFER, MATTHIAS RAUNHARDT, DANIEL SPRECHER, JINJUN LIU, and FR ÉDÉRIC MERKT, ETH Zürich, Laboratorium f ür Physikalische Chemie, Wolfgang-Pauli-Strasse 10, 8093 Z ürich, Switzerland. The threshold ionization spectra of He (a ) reveal a dense structure of very sharp features that can be attributed to transitions to Rydberg states converging on the first ( ) rotational levels of the X 1 ground ionic state. Many of these states associated with rotationally excited levels of the ion core (rotational quantum number ) are embedded in the ionization continua associated with the and ionization channels. The rotational autoionization dynamics is complex and is strongly influenced by the application of weak electric fields. Several series are immune to ionization and the corresponding states are metastable. The energy level structure and the rotational autoionization dynamics have been analyzed by multichannel quantum defect theory (MQDT). An interpretation of the effects of the electric fields on the autoionization dynamics is proposed. 174 TJ03 OBSERVATION OF A LINEAR ISOMER OF THE C -Xe VAN DER WAALS COMPLEX 15 min 2:04 KENG SENG THAM, JUN-MEI CHAO, GUIQIU ZHANG, ANTHONY J. MERER, YEN-CHU HSU, Institute of Atomic and Molecular Sciences, Academia Sinica, P. O. Box 23-166, Taipei 10617, R. O. C.; WEI-PING HU, Department of Chemistry, National Chung-Cheng University, Taiwan, R. O. C. Our emission spectra of the C -Xe vdW (van der Waals) complex obtained near the 2 band of the ÃX̃ system of C showed that a stable linear isomer is present at high C -bending vibrational levels (1 4) of the ground electronic state. Ab initio calculations at the level of CCSD(T)/cc-pVTZ (effective core potential of the Xe atom) support our spectral assignments. The linear isomer lies about 250 cm above the T-shaped isomer. From the calculated potential, large amplitude vdW bending motion is expected in the high 1 levels; this explains the congested emission spectra observed from vdW bands near the 2 band of C . Molecular orbitals at the level of HF-SCF showed that bonding with the 5 orbital of the Xe atom in a linear configuration (along the -axis of C ) is stabilized by mixing some high-lying $ bonding character into one of the C-C bonds. This type of bonding is not possible in the Ar and Kr complexes because in these two complexes 3 or 4 orbitals of the rare gas atoms are used. The isomerization from the T-shaped isomer to the linear isomer probably occurs rapidly in the à state. TJ04 15 min 2:21 THE ELECTRONIC SPECTRUM AND MOLECULAR STRUCTURE OF THE ARSENYL (H As=O) FREE RADICAL SHENG-GUI HE, Institute of Chemistry, Chinese Academy of Sciences, Zhongguancun, Beijing 100080, P.R.C.; FUMIE X. SUNAHORI, JIE YANG, AND DENNIS J. CLOUTHIER, Department of Chemistry, University of Kentucky, Lexington, KY 40506-0055. The H As=O radical has been identified for the first time by laser-induced fluorescence (LIF) and single vibronic level (SVL) emission techniques. The radical was generated by a pulsed electric discharge in a mixture of AsH and CO and electronic transition in the 510-410 nm region. high-pressure argon and detected by observation of the Moderate resolution LIF and SVL emission spectra of H AsO, D AsO, and HDAsO have been recorded and analysis shows unequivocally that the spectrum is due to the arsenyl radical. High-resolution spectra of the bands of H AsO and D AsO, which consist of strong -type and weaker -type transitions, revealed spin-splittings and small, but significant arsenic hyperfine splittings due to a Fermi contact interaction in the ground state. The effective molecular structures of H AsO in the ground and excited states have been determined from the rotational constants and will be discussed in the context of the analogous nitroxyl (X N=O) and phosphonyl (X P=O) radicals. TJ05 DISCOVERY OF THE ELECTRONIC SPECTRA OF HPS AND DPS 10 min 2:38 ROBERT A. GRIMMINGER, JIE WEI, BLAINE ELLIS and DENNIS J. CLOUTHIER, Department of Chemistry, University of Kentucky, Lexington, KY, 40506; ZHONG WANG and TREVOR SEARS, Department of Chemistry, Brookhaven National Lab, Upton, NY 11973. The hitherto unknown electronic spectrum of the closed shell transient molecule HPS has been observed in the 685 - 846 nm region by laser-induced fluorescence and single vibronic level emission techniques. HPS (and DPS) were produced in a pulsed electric discharge jet using a precursor mixture of 3% PH and 1% H S (or PD and D S) in high pressure A electronic transition on the basis of chemical argon. The weak set of observed bands are assigned to the A evidence, isotope shifts and the correspondence of the vibrational frequencies, excitation energy, and band contours with predictions based on our own high level ab initio calculations. Theory predicts that the HPS bond angle decreases on electronic excitation, contrary to expectations based on Walsh diagrams. 175 TJ06 15 min 2:50 THE ELECTRONIC SPECTRA OF THE JET-COOLED BORON DIFLUORIDE (BF ) AND BORON DICHLORIDE (BCl ) FREE RADICALS JIE YANG, JIE WEI, FUMIE SUNAHORI, MOHAMMED GHARAIBEH, BLAINE ELLIS, ALFRED CHEN, and DENNIS J. CLOUTHIER, Department of Chemistry, University of Kentucky, Lexington, KY 40506-0055, USA; SHENG-GUI HE, Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, The Chinese Academy of Sciences, Zhongguancun, Beijing 100080, PRC. transitions of Laser-induced fluorescence (LIF) and single vibronic level (SVL) emission spectra of the the jet-cooled boron difluoride (BF ) and boron dichloride (BCl ) radicals have been observed. In each case, the radical was produced in a pulsed discharge jet using a precursor mixture of the corresponding boron halide (BF or BCl ) in high pressure argon. Due to a large change in geometry from a bent ground state to a linear excited state, the LIF spectra are very extensive and the emission spectra show long bending progressions. Strong LIF bands of BF and BF (from isotopically enriched BF ) were observed in the cm region and isotope shifts were identified. The rotational constants obtained from high resolution LIF spectra of the two isotopologues were used to determine the effective zero-point structure of the ground state. For BCl , weaker and much more complex LIF spectra, which have as yet defied vibrational analysis, were recorded in the cm region. SVL emission spectra of five isotopologues have been obtained, affording a detailed vibrational analysis of the ground state of BCl . TJ07 ULTRAHIGH-RESOLUTION SPECTROSCOPY OF THE 15 min 3:07 TRANSITION OF NO RADICAL SHUNJI KASAHARA, KENICHIROU KANZAWA, YOSUKE SEMBA, KAZUTO YOSHIDA, Molecular Photoscience Research Center, Kobe University, Kobe 657-8501, Japan; MASAAKI BABA, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan; TAKASHI ISHIWATA, Faculty of Information Sciences, Hiroshima City University, Hiroshima 731-3194, Japan; EIZI HIROTA, The Graduate University for Advanced Studies, Kanagawa 240-0193, Japan. Ultrahigh-resolution spectroscopic technique is powerful tool for studying the structure and dynamics of excited molecules in detail and unambiguously. Rotationally resolved high-resolution fluorescence excitation spectra of the band of the transition of NO radical has been observed by crossing a single-mode laser beam perpendicular to a collimated molecular beam. The observed line width was 25 MHz, which was the residual Doppler width, and the absolute wavenumber was caliblated with accuracy 0.0001 cm . The rotational structure of this band has been reported by Carter et al. a , but the rotational assignment is still remained because the spectrum is too complicated. We are trying to assign the observed rotational lines by using the combination difference in the ground state. Besides the main rotational lines, a number of small lines were observed as the background. It suggests the 1 level is interacts with the other vibronic levels. a R. T. Carter, K. F. Schmidt, H. Bitto, and J. R. Huber, Chem. Phys. Lett., 257, 297 (1996). 176 TJ08 15 min 3:24 - ABSORPTION SPECTRA OF CYCLOPENTYL AND CYCLOHEXYL PEROXY OBSERVATION OF THE RADICALS BY CAVITY RINGDOWN SPECTROSCOPY PHILLIP S. THOMAS, RABI CHHANTYAL-PUN, AND TERRY A. MILLER, Laser Spectroscopy Facility, Department of Chemistry, The Ohio State University, 120 W. 18th Avenue, Columbus OH 43210. Alkyl peroxy radicals are important intermediates in combustion chemistry. These molecules, formed from the addition of oxygen to organic radicals, are also pivotal species in atmospheric oxidation of organic compounds. Previous spectroscopic - transition; however, this system cannot be used to exact detailed structural studies have monitored the intense - manifold has been used to selectively information due to predissociation in the state. On the other hand, the weak distinguish between isomers and conformers of a number of straight and branched aliphatic peroxy radicals. This research, mediated by cavity ringdown spectroscopy (CRDS) is now extended to include cyclic chain systems, beginning with cyclopentyl and cyclohexyl peroxy radicals. - CRDS spectra of cyclopentyl, cyclohexyl, and cyclohexylIn this work, we present a full vibrational analysis of the d peroxy radicals. For cyclohexyl peroxy, the spectrum obtained is consistent with calculated predictions for both axial and equatorial gauche conformers; for cyclopentyl peroxy, a single gauche conformer is observed. Contrary to our expectations, we see no clear evidence for the cis- conformers for either peroxy. Shapes of the electronic origin bands are well reproduced by hot band simulations, and Franck-Condon simulations facilitate assignment of the numerous active COO bending vibrations observed for cyclohexyl peroxy. Mode mixing appears to have important consequences on the spectrum in the O-O stretch region. Intermission TJ09 THE GAS-PHASE SPECTRA OF THE 1-INDANYL RADICAL 15 min 4:00 TYLER P. TROY, MASAKAZU NAKAJIMA, NAHID CHALYAVI, RAPHA ËL G. C. R. CLADY, KLAAS NAUTA, SCOTT H. KABLE, and TIMOTHY W. SCHMIDT, School of Chemistry, The University of Sydney, NSW 2006, AUSTRALIA. The gas-phase resonant two color two photon ionization (R2C2PI) spectrum of the 1-indanyl radical (m/z=117) has been identified in the region 20800 — 22600 cm in a molecular beam. The radical was produced from the discharge of 1 % indene in Argon . Laser induced fluorescence (LIF) spectra were recorded in the same region revealing those features observed in R2C2PI. Other precursor molecules were investigated and it was found that the indane precursor resulted in the strongest signal. The fluorescence of the 1-indanyl radical origin band (21158 cm ) was dispersed in order to determine the ground state vibrational energies. The dispersed fluorescence (DF) spectrum is consistent with the previously observed condensed-phase emission spectrum of the 1-indanyl radical a . The DF values were compared with those ground state energies determined by DFT. Franck-Condon factors computed based on the ab initio results showed good agreement with the observed spectrum. Based on the theoretical results we assigned the observed bands. The LIF spectrum contained other bands inconsistent with the 1-indanyl radical. These have been determined to be carried by 1-phenylpropargyl radical b and another currently unknown radical determined by R2C2PI to have m/z=133. a T. b N. Izumida, K. Inoue, S. Noda, and H. Yoshida, Bull. Chem. Soc. Jpn. 54, 2517 (1981). J. Reilly, D. L. Kokkin, M. Nakajima, K. Nauta, S. H. Kable, and T. W. Schmidt, J. Am. Chem. Soc. 130, 3137 (2009). 177 TJ10 SPATIALLY SEPARATING STRUCTURAL ISOMERS OF NEUTRAL MOLECULES 15 min 4:17 FRANK FILSINGER, JOCHEN KÜPPER, GERARD MEIJER, Fritz-Haber-Institut der Max-PlanckGesellschaft, Faradayweg 4-6, 14195 Berlin, Germany; JONAS L. HANSEN, LOTTE HOLMEGAARD, JENS H. NIELSEN, IFTACH NEVO, JOCHEN MAURER, and HENRIK STAPELFELDT, Department of Chemistry, University of Aarhus, DK-8000 Aarhus C, Denmark. Large (bio)molecules exhibit multiple conformers (structural isomers), even under the cold conditions present in a supersonic jet. For various applications, i. e., scattering experiments or time resolved studies, it would be highly desirable to prepare molecular packets of individual conformers. It is well known that polar molecules can be manipulated using strong electric fields. Recently, we have demonstrated that electrostatic deflection of a molecular beam can be used for quantum-state selection of large molecules. a Here, we demonstrate how this quantum state selectivity can be exploited to spatially separate the individual conformers of large molecules based on their distinct mass-to-dipole moment (m/) ratios. In a proof-of-principle experiment, we have spatially isolated both, cis and trans, conformers of 3-aminophenol. We will compare this approach to conformer selection using alternating gradient (dynamic) focusing in an m/-selector. b a L. b F. Holmegaard et al., Phys. Rev. Lett., 102, (2009),023001 Filsinger et al., Phys. Rev. Lett. 100, (2008),133003 TJ11 15 min 4:34 SLOW ELECTRON VELOCITY MAPPING FOR THE STUDY OF CATIONIC STATES OF AROMATIC MOLECULES CHIH-HSUAN CHANG, Department of Chemistry, Brookhaven National Laboratory, Upton, New York 11973; GARY V. LOPEZ and PHILIP M. JOHNSON, Department of Chemistry, Stony Brook University, Stony Brook, New York 11794; TREVOR J. SEARS, Department of Chemistry, Brookhaven National Laboratory, Upton, New York 11973 and Department of Chemistry, Stony Brook University, Stony Brook, New York 11794. Slow electron velocity mapping (SEVM), a variant of velocity map imaging (VMI), has been implemented to study the vibronic levels of ionized aromatic molecules. The technique of velocity map imaging has been shown to be a powerful method and has gained enormous impetus since its development by Parker et al. a SEVM is a versatile photoelectron spectroscopy method that reveals the low energy ionic vibrational structure and also retains the VMI capability to measure angular distributions of the photoelectron. Photoelectron images of the cationic vibrational structure and their angular dependence reflect the character of both the final state and the neutral level from which ionization occurs. Hence, from the photoelectron energies and angular distributions, information on the vibronic character of levels in the first neutral excited state (S1) and the cation state (D0) of molecules can be obtained by resonantly enhanced multiphoton ionization (REMPI). Phenylacetylene (PA) and fluorene were studied and probed using REMPI excitation schemes and the SEVM technique. In the case of PA, the angular distribution of the electrons correlated with ioization via the 6a mode involving the breathing of the benzene ring shows a distinct mode-dependent effect, illustrating the technique. However, in the case of fluorene, only the vibrationless level and stretching vibrational modes in the cation state showed Franck-Condon activity and had nearly isotropic photoelectron distributions. Future work on polycyclic aromatic hydrocarbon systems related to fluorene, such as carbazole, dibenzofuran, and dibenzothiophene is planned. Acknowledgments: Work at Brookhaven National Laboratory was carried out under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy. a A. T. J. B. Eppink and D. H. Parker Rev. Sci. Instrum. 68, 3477 (1997). 178 TJ12 15 min 4:51 IONIZATION ENERGY MEASUREMENTS AND SPECTROSCOPY OF HfO AND HfO J. M. MERRITT, V. E. BONDYBEY, and M. C. HEAVEN, Department of Chemistry, Emory University, Atlanta, GA 30322. Rotationally resolved spectra of the HfO cation have been recorded using the pulsed field ionization zero electron kinetic energy (PFI-ZEKE) technique. The - band system in HfO was resonantly excited to provide vibrational and rotational state selectivity in the two photon ionization process. Using the PFI-ZEKE technique a value of 7.91687(10) eV was determined for the ionization energy (IE) of HfO, 0.37 eV higher than the values reported previously using electron impact ionization measurements. Underestimation of the IE in the previous studies is attributed to ionization of thermally excited states. A progression in the HfO stretching vibration up to = 4 was observed in the PFI-ZEKE spectrum, allowing for determination of the ground electronic state vibrational frequency of = 1017.7(10) cm and anharmonicity of 7 ? = 3.2(2) cm . The rotational constant of HfO was determined to be 0.403(5) cm . Benchmark theoretical ab initio calculations were carried out in order to explore the effects of electron correlation on the predicted molecular properties. Survey scans utilizing laser induced fluorescence and resonance enhanced multiphoton ionization detection revealed many previously unassigned bands in the region of the F-X and G-X bands of HfO, which we attribute to nominally forbidden singlet triplet transitions of HfO. TJ13 15 min 5:08 HIGH RESOLUTION ELECTRONIC SPECTROSCOPY OF THE ARGON VAN DER WAALS COMPLEXES OF 1, 2, 3, 6, 7, 8-HEXAHYDROPYRENE IN THE GAS PHASE. a PHILIP J. MORGAN, ADAM J. FLEISHER, JOSEPH R. ROSCIOLI b and DAVID W. PRATT, Department of Chemistry, University of Pittsburgh, PA 15260. The study of van der Waals complexes provides structural and dynamical information about the weak chemical forces that exist between aromatic molecules and rare gas atoms. In this report, we describe the rotationally resolved fluorescence excitation spectra of the S S origin bands of the single argon atom complexes of 1, 2, 3, 6, 7, 8-hexahydropyrene. Analysis of the spectra provides information about the geometries of both conformers of the bare molecule and their argon complexes in both electronic states. The equilibrium positions of the argon atom in both conformers will be discussed. a Work supported by NSF (CHE-0615755) address: JILA, National Institute of Standards and Technology and University of Colorado, and Department of Chemistry and Biochemistry, University of Colorado, Boulder, CO 80309. b Present TJ14 15 min 5:25 NONRADIATIVE DECAY PATHWAYS OF THE FIRST EXCITED ELECTRONIC STATES OF 1:1 HYDROGEN BONDED COMPLEXES OF 7-AZAINDOLE WITH PHENOL AND FORMAMIDE MOITRAYEE MUKHERJEE, ANAMIKA MUKHOPADHYAY AND TAPAS CHAKRABORTY, Physical Chemistry Department, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700032. On UV excitation, the monomer and doubly hydrogen-bonded homodimer of 7-azaindole decay via two radically different photophysical pathways. While the monomer emits intense UV fluorescence, the dimer undergoes ultrafast nonradiative relaxation to a tautomeric configuration and emits green fluorescence. The latter channel is also preferred by the complexes of 7-azaindole with aliphatic alcohols, and the propensity of the tautomerization process is determined by acidity of the alcohols. In contrast, we report here that in spite of being a stronger acid the aromatic alcohol phenol hinders the said tautomerization in a 1:1 complex environment, and the excitation energy is funnelled through a new nonradiative decay channel. We also have measured the medium effect on the process, and propose a mechanism for relaxation of the locally excited state in terms of electronic energy transfer coupled with proton transfer between the two dimer moieties. On the other hand, in case of 7-azaindole-formatide 1:1 complex, sharp bands in the gas phase fluorescence excitation spectrum are displayed only for excitations with about 200 cm excess vibronic energy. The medium effect of the onset of the nonradiative decay process has been probed by performing the measurement in a cyclohexane solution at room temperature. The details of the finding will be presented in the talk. 179 TJ15 15 min 5:42 HYDROGEN BONDING EFFECTS ON NONRADIATIVE CHANNELS OF INDOLE BY APROTIC POLAR SOLVENTS MOITRAYEE MUKHERJEE, TAPAS CHAKRABORTY, Physical Chemistry Department, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700032. We report here the fluorescence properties of 1:1 hydrogen bonded complexes of indole with a series of aprotic polar solvents in cold inert gas inert gas matrices below 10K. Measurements of the dispersed fluorescence spectra following selective excitations to various vibronic levels in S of the monomer as well as complexes display the hydrogen bonding effects on Franck-Condon active modes in the emission spectra. To estimate the matrix effect on the observed results, measurements have been performed also in a hydrocarbon solvent at room temperature, and it is noted that complexation causes significant enhancement of the quantum yield of fluorescence. The observed spectral behaviour contrasts the predictions of some of the recent theoretical studies of solvent effects on the non-radiative decay channels of indole, and we propose here alternative mechanisms. 180 WA. PLENARY SESSION WEDNESDAY, JUNE 24, 2009 – 8:30 AM Room: AUDITORIUM, INDEPENDENCE HALL Chair: MALCOLM CHISHOLM, The Ohio State University, Columbus, Ohio WA01 POTENTIOLOGYa IN SPECTROSCOPY: IT MATTERS 40 min 8:30 ROBERT J. LE ROY, Guelph-Waterloo Centre for Graduate Work in Chemistry and Biochemistry, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada. Spectroscopists have long attempted to summarize what they know about small molecules in terms of a knowledge of potential energy curves or surfaces. For most of the past century, this involved deducing polynomial-expansion force-field coefficients from energy level expressions fitted to experimental data, or for diatomic molecules, by generating tables of many-digit RKR turning points from such expressions. In recent years, however, it has become increasingly common either to use high-level ab initio calculations to compute the desired potentials, or to determine parametrized global analytic potential functions from direct fits to spectroscopic data. In the former case, this invoked a need for robust, flexible, compact, and ‘portable’ analytic potentials for summarizing the information contained in the (sometimes very large numbers of) ab initio points, and making them ‘user friendly’. In the latter case, the same properties are required for potentials used in the least-squares fitting procedure. In both cases, there is also a cardinal need for potential function forms that extrapolate sensibly, beyond the range of the experimental data or ab initio points. This talk will describe some recent developments in this area, and make a case for what is arguably the ‘best’ general-purpose analytic potential function form now available. Applications to both diatomic molecules and simple polyatomic molecules will be discussed. a potentiology (noun): study focusing on the development of new interatomic pair potential forms; sometimes pursued in an obsessive compulsive manner [The New Yorel Dictionary (2002, unpublished)]. 181 WA02 40 min 9:15 STRUCTURE AND RADIATIONLESS TRANSITION OF PAHS : ULTRAHIGH-RESOLUTION SPECTROSCOPY AND AB INITIO CALCULATION MASAAKI BABA, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan. Polycyclic aromatic hydrocarbons (PAHs) are fascinating objects of basic studies on molecular structure and excited-state dynamics. We have observed and analyzed rotationally resolved ultrahigh-resolution spectra of the transition of naphthalene, anthracene, pyrene and perylene (all symmetry) in collimated supersonic jets. We conclude that radiationless transitions are all slow in the zero-vibrational level of the isolated PAH molecule. Possible radiationless processes are intersystem crossing (ISC), internal conversion (IC), and predissociation. a Predissociation does not take place because all of the bond energies are larger than the excitation energy. The observed radiationless process has been presumed to be ISC so far. However, it is inconsistent with El-Sayed’s rule that spin-orbit interaction is very weak between the $$ and $$ states. b We have observed Zeeman splitting of each rotational line and shown that the magnetic moment is very small in the state. Therefore, the main radiationless process is not ISC to the triplet state, but IC to the hot ground state. IC is caused by non-Born-Oppenheimer vibronic interaction, c which is expected to be very weak if the molecular structure is identical for both electronic states. The experimentally determined rotational constants are almost identical for the and states. It is consistent with the observed long lifetime and high fluorescence quantum yield of PAHs. We carried out * 9 99 calculation, and the resultant values of rotational constants of the state are in extremely good coincidence with the experimental ones for naphthalene and anthracene. On the contrary, for the excited state, it is necessary to perform huge SAC-CI calculation to obtain satisfactory results. Fast IC has been found, for instance, in high vibrational levels of benzene (channel 3), which is due to unavoided potential crossing (conical intersection). However, it is not likely in large PAHs because of the small geometrical change upon electronic excitation, which has been revealed by accurate determination of rotational constants. a H. Katô and M. Baba, Chem. Rev., 95, 2311 (1995) El-Sayed, J. Chem. Phys., 38, 2834 (1963) c S. H. Lin, J. Chem. Phys., 44, 3759 (1965) b M. Intermission WA03 40 min 10:20 HALOGEN BONDS AND HYDROGEN BONDS IN THE GAS PHASE: SIMILARITY REVEALED THROUGH ROTATIONAL SPECTROSCOPY. A. C. LEGON, School of Chemistry, University of Bristol, Bristol, BS8 1TS, U.K.. Many hydrogen-bonded species B HX, where B is a simple Lewis base and X is halogen atom, were extensively investigated by rotational spectroscopy in the 1980/90’s to yield various properties of the isolated complexes. Systematic variation of B, and then X, allowed generalisations concerned with the hydrogen bond to be identified. More recent examinations of several series of complexes B XY, where XY is either a homo- or hetero-dihalogen molecule, have revealed striking parallelisms between the properties of the B XY and those of their hydrogen-bonded counterparts B HX, thereby suggesting that the generalisations made for the hydrogen-bonded series also apply to B XY. Accordingly, the weak intermolecular bond in B XY has been called a halogen bond. Here, attention will focus mainly on angular geometry for selected pairs B HCl and B ClF. It will be shown that B HCl and B ClF are essentially isomorphous for a given B, but with the hydrogen bond exhibiting a greater propensity to be non-linear. To test the effect that weakening the hydrogen bond has on its deviation from linearity, reference will be made to some complexes B HCCH in which ethyne is the H-atom donor. 182 WA04 IMAGING PAIR-CORRELATED PREDISSOCIATION OF HYDROGEN-BONDED DIMERS 40 min 11:05 HANNA REISLER, Department of Chemistry, University of Southern California, Los Angeles, CA 900890482. Photofragment imaging is used to interrogate state-specific energy flow patterns in predissociation of hydrogen-bonded mixed dimers of polyatomic species. Imaging-based dynamic spectroscopy provides action spectra of photofragments following infrared excitation of selected vibrational transitions in the dimer. Pair-correlated energy distributions are inferred from velocity map images of specific product rovibronic states. Predissociation of dimers of acetylene with hydrogen chloride and ammonia will be discussed, as well as the ammonia-water dimer. Dissociation energies are determined and compared with theory and energy flow patterns are analyzed. The experiments demonstrate that while general propensity rules exist on how energy is coupled to the dissociation coordinate, it is the fine details of how excitation is deposited in the dimer and its subsequent propagation through the two dimer moieties that give rise to state-specific effects. Calculations based on the hard-ellipsoid model illustrate how kinematic constraints can determine points of impact and the ensuing transformation of linear to angular momentum. 183 WF. DYNAMICS WEDNESDAY, JUNE 24, 2009 – 1:30 PM Room: 160 MATH ANNEX Chair: FLEMING CRIM, University of Wisconsin, Madison, Wisconsin WF01 STUDIES OF THE PREDISSOCIATED, QUASILINEAR OPTICAL DOUBLE RESONANCE SPECTROSCOPY B 15 min 1:30 STATE OF CH Cl AND CD Cl BY OPTICAL- C. TAO, C. MUKARAKATE AND S. A. REID, Department of Chemistry, Marquette University, Milwaukee, WI 53233. Last year at this meeting, we reported studies of the predissociated, quasilinear B state of fluorocarbene (CHF and CDF) using a fluorescence dip detected optical-optical double resonance technique via the A state.a Recently, we have extended these observations to chlorocarbene, measuring OODR spectra of both CH Cl and CD Cl. By recording OODR spectra of both isotopomers, we are able to pinpoint the origin of the B state, while lies near 22 400 cm . In contrast to CHF, the B origin in chlorocarbene lies below the energetic threshold of the lowest dissociation channel, C( P) + HCl. However, at higher energies several channels open up, including C-H and C-Cl bond fission, and the OODR spectra show significant lifetime broadening. Trends in the measured linewidths with energy will be discussed. a C. Tao, S. A. Reid, T. W. Schmidt, and S. H. Kable, J. Chem. Phys. 125, 051105 (2007). WF02 PHOTOFRAGMENTATION DYNAMICS OF 15 min 1:47 JOSHUA P. MARTIN, JOSHUA P. DARR, W. CARL LINEBERGER, JILA and Department of Chemistry and Biochemistry, University of Colorado, Boulder, CO 80309; ANNE B. MCCOY, Department of Chemistry, The Ohio State University, Columbus, OH 43210. We report photofragmentation studies of mass-selected ( =0-18) cluster anions following 400, 500 and 600 nm excitation. Photodissociation of following excitation 19 a 500 nm photon results exclusively in an anionic photoproduct. However, excitation at either 400 nm or 600 nm results in 30% and 70% anionic photoproducts. Complexation of with two or more molecules opens a third product channel, recombination of the chromophore on the ground state, a channel that is observable at all three photon energies. The product branching ratios for photodissociation of show sharp contrast to trends previously observed in dihalide studies of )* and , but are strikingly similar to results found for . Notably, a peak in the percentage of recombined photoproducts observed as a function of the number of solvent molecules shifts to larger values as photon energy increases and does not reach 100% in the first solvation shell. It is likely that an intracluster reaction involving formation of the molecule plays a significant role in the dynamics observed following excitation of the anion. Supported by NSF and AFOSR 184 WF03 15 min 2:04 DISSOCIATION DYNAMICS OF THE IBr (CO ) VAN DER WAALS CLUSTER: A DIRECT VIEW OF SOLVENTDRIVEN NON-ADIABATIC TRANSITIONS LEONID SHEPS, ELISA M. MILLER, ROBERT PARSON, and W. CARL LINEBERGER a , JILA, Department of Chemistry and Biochemistry, University of Colorado at Boulder, Boulder, CO 80309; MATTHEW A. THOMPSON, US Naval Research Lab, Washington, DC 20375; SAMANTHA HORVATH and ANNE B. McCOY, Department of Chemistry, The Ohio State University, Columbus, OH 43210. We present the results of several time-resolved pump-probe experiments that explore the photodissociation of a simple dihalide anion, IBr , clustered with a single CO solvent molecule. A 100-fs pump laser pulse (4=800 or 400 nm) initiates the dissociation of IBr on either the A’ or the higher-lying B state of the anion. A second, time-delayed, tunable 100-fs laser pulse probes the subsequent dynamics by photoelectron spectroscopy. In the bare anion the A’ and B states correlate exclusively to the I or the Br photoproducts, respectively. However, the addition of a single solvent molecule induces charge switching in a subset of the excited molecules midway through the dissociation, resulting in mixed photoproduct distributions (both I and Br ) from both states. In the case of dissociation on the A’ state (which correlates asymptotically to I ), the CO solvent molecule produces charge switching to Br in about 3+ of the products, even though it cannot induce potential curve crossings. Electronic structure calculations and MD simulations point to a subtle mechanism for these non-adiabatic charge hops, involving the effects of the CO bending vibration to bridge the energetic gap of the charge transfer. Conversely, for dissociation on the higher-lying B state (which correlates asymptotically to Br ), the photoproduct ratio is about 60+ Br :40+ I , indicating large amounts of charge switching. In this case it is energetically possible for the CO molecule to cause the B state to cross with the nearby a’ state, which correlates with I . The charge switching mechanism, which is likely to be more complex than for the A’ state, will be discussed in detail. a We gratefully acknowledge the funding from NSF and AFOSR WF04 15 min 2:21 ULTRAFAST STUDY OF BROMINE RADICAL IN SOLUTION: THE ROLE OF COMPLEXES AND VIBRATIONAL EXCITATION STACEY L. CARRIER, THOMAS J. PRESTON, ANDREW C. CROWTHER, F. FLEMING CRIM, The University of Wisconsin - Madison Department of Chemistry, 1101 University Avenue, Madison, WI 53705. The bromine radical is an interesting species to interrogate with vibrationally mediated chemistry. It forms a long-lived complex in the liquid phase, and hydrogen abstraction from a solvent molecule is endothermic. Photolysis of a bromine precursor forms an iso-compound within 1 ps, which decays to a radical-solvent complex on a 10 ps timescale. We use these features to examine the reaction of the Br radical complex with an excited C-H oscillator. A potential reaction pathway that becomes available upon vibrational excitation is H abstraction from the excited oscillator by Br. Vibrational excitation can also cause dissociation of the Br complex. We follow the progress of these reactions using transient broadband UV-Vis spectroscopy. 185 WF05 15 min 2:38 LASER-INDUCED ALIGNMENT AND ORIENTATION OF QUANTUM-STATE-SELECTED LARGE MOLECULES FRANK FILSINGER, JOCHEN KÜPPER, GERARD MEIJER, Fritz-Haber-Institut der Max-PlanckGesellschaft, Faradayweg 4-6, 14195 Berlin, Germany; LOTTE HOLMEGAARD, JENS H. NIELSEN, IFTACH NEVO, JONAS L. HANSEN, and HENRIK STAPELFELDT, Department of Chemistry, University of Aarhus, DK-8000 Aarhus C, Denmark. For many experiments in chemistry and physics, i. e., reactive scattering, X-ray or electron diffraction experiments, a high level of control over the spatial orientation of molecules would be very beneficial. It is well known that molecules can be aligned and oriented in space using strong dc electric fields or laser pulses. a Here, we demonstrate that the degree of laserinduced alignment and orientation can be considerably improved, if quantum state selected samples are used. b A strong inhomogeneous electric field is used in a Stern-Gerlach-type experiment to disperse iodobenzene molecules in a supersonic jet according to their rotational quantum state. Molecules in the lowest rotational quantum states are deflected most and can be used as targets for further experiments. This method is widely applicable to all, small and large, polar molecules and should eventually enable experiments on pure samples of strongly aligned or oriented ground-state molecules offering new prospects in molecular sciences. a H. b L. Stapelfeldt and T. Seideman, Rev. Mod. Phys., 75, (2003), 543 Holmegaard et al., Phys. Rev. Lett., 102, (2009), 023001 Intermission WF06 THE QUANTITATIVE ANALYSIS OF THE ROTATIONAL SPECTRUM OF NCNCS 15 min 3:15 MANFRED WINNEWISSER, BRENDA P. WINNEWISSER, IVAN R. MEDVEDEV, and FRANK C. DE LUCIA, Department of Physics, The Ohio State University, Columbus Ohio, 432101106; STEPHEN C. ROSS, Department of Physics and Centre for Laser, Atomic, and Molecular Sciences, University of New Brunswick, P.O. Box 4400, Fredericton NB E3B 5A3, Canada; and JACEK KOPUT, Department of Chemistry, Adam Mickiewicz University, 60-780 Poznan, Poland. The analysis of the rotational data which were the basis of our two previous publications a b about NCNCS as an example of quantum monodromy has been completed, and the data extended to include the 6th excited state of the quasilinear bending mode. This talk will present the results of fitting the data with the GSRB Hamiltonian, which provides structural and potential parameters. Ab initio calculations contributed some parameters that could not be determined from the data. The predicted variation of the expectation value of (, which is the complement of the CNC angle, and of the electric dipole transition moment, upon rovibrational excitation indicate the mapping of monodromy in the potential function into these properties of the molecule. a B. b M. P. Winnewisser, M. Winnewisser, I. R. Medvedev, M. Behnke, F. C. De Lucia, S. C. Ross and J. Koput Phys. Rev. Lett. 95 (243002), 2005. Winnewisser, B. P. Winnewisser, I. R. Medvedev, F. C. De Lucia, S. C. Ross and L. M. Bates J. Mol. Struct. 798 (1-26), 2006. 186 WF07 15 min 3:32 ANOMALOUS CENTRIFUGAL DISTORTION AND A GENERALIZED DEFINITION OF A QUASILINEAR MOLECULE BRENDA P. WINNEWISSER, MANFRED WINNEWISSER, IVAN R. MEDVEDEV, and FRANK C. DE LUCIA, Department of Physics, The Ohio State University, Columbus Ohio, 432101106; JACEK KOPUT, Department of Chemistry, Adam Mickiewicz University, 60-780 Poznan, Poland; and STEPHEN C. ROSS, Department of Physics and Centre for Laser, Atomic, and Molecular Sciences, University of New Brunswick, P.O. Box 4400, Fredericton NB E3B 5A3, Canada. Monodromy in the bending potential function is mapped into the rotation-bending spectrum, as shown in the previous talk. The form this takes in NCNCS for the parameter corresponding to in an asymmetric rotor will be demonstrated. Years ago, extremely large values of and , as well as higher order terms, were found for HNCO, HNCS, and most importantly, H O, and discussed as “anomalous centrifugal distortion”. At that time no one understood the physical origin of the phenomenon, although we knew it must have something to do with the bending mode. Today we can correlate it directly with monodromy in the bending potential function. The early definition of a quasilinearity parameter a, allowing us to classify molecules with a more or less large amplitude bending mode, limited the concept to those that were rather close to the linear limit, specifically with the ground state below or only just above the top of the barrier to linearity. Recent work has shown that a considerably larger group of molecules should actually be considered quasilinear. This talk will show why this is so, and conclude with the definition of a generalized quasilinearity parameter which can be used to implement such a classification. a K. Yamada and M. Winnewisser Z. Naturforsch. 31A (139-144), 1976. WF08 15 min 3:49 REACTION DYNAMICS OF VIBRATIONALLY EXCITED CH D MOLECULES WITH CHLORINE CHRISTOPHER J. ANNESLEY, ANDREW E. BERKE, F. FLEMING CRIM, The University of Wisconsin Madison Department of Chemistry, 1101 University Avenue, Madison, WI 53705. State-resolved reactions of CH D molecules with Cl atoms probe the consumption and disposal of vibrational and translational energy. Using state-resolved detection it is possible to determine the relative effects of these on the reaction and gain a better understanding of the reactivity differences between modes. In one recent experiment, we explored the effect of exciting either the combination of the C-H symmetric stretch and the C-D stretch ( + ), the combination of the C-D stretch and the C-H antisymmetric stretch ( + ), or the combination of the C-D stretch and the first overtone of the CH bend ( + 2 ). The reaction dynamics largely follow a spectator picture in which the surviving bond retains its initial vibrational excitation. In at least 80% of the reactive encounters of vibrationally excited CH D with Cl, cleavage of the C-H bond produces CH D radicals with an excited C-D stretch, and cleavage of the C-D bond produces CH radicals with an excited C-H stretch. Deviations from the spectator picture seem to reflect mixing in the initially prepared eigenstates and, possibly, collisional coupling during the reaction. 187 WF09 15 min 4:06 THE Cl+H HCl+H REACTION INDUCED BY IRRADIATION OF Cl IN SOLID PARAHYDROGEN SHARON C. KETTWICH and DAVID T. ANDERSON, Department of Chemistry, University of Wyoming, Laramie, WY 82071-3838, USA; PAUL L. RASTON, Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada. Matrix isolation spectroscopy is a technique which enables highly reactive species to be trapped in a host environment and studied spectroscopically. Solid parahydrogen (H ) has been employed as a matrix host because of its interesting quantum mechanical properties and also because of its general inertness towards trapped dopants. However, in some cases H can react with impurities yielding new product molecules and providing insight into non-classical reaction pathways. In this talk I will present the results from a series of experiments where molecular chlorine (Cl ) doped H crystals were exposed to two different irradiation schemes (namely only or conditions) that gave rise to very different products. Cl doped H crystals irradiated with light produced almost exclusively (+) isolated Cl-atom photofragments, indicating the reaction Cl+H & HCl+H is not readily occurring. Cl doped H exposed simultaneously to irradiation and broadband @ light yielded HCl photoproducts indicating that the following reaction is playing a significant (+) role in the in situ photochemistry: Cl+H & HCl+H. The kinetic analysis of these experiments with two very different reaction pathways for only or conditions will be presented. Further, the results of current investigations involving spin-orbit excited Cl-atoms generated using photons will be discussed in order to explore the intriguing possibility of non-Born Oppenheimer reaction dynamics in the simple Cl+H reaction. WF10 15 min 4:23 THEORETICAL STUDIES OF THE ROLE OF VIBRATIONAL EXCITATION ON THE DYNAMICS OF THE HYDROGEN-TRANSFER REACTION OF F( P) + HCl FH + Cl( P) SARA E. RAY, GÉ W. M. VISSERS and ANNE B. McCOY, Department of Chemistry, The Ohio State University, Columbus, OH 43210. Hydrogen-transfer reactions are probed through vibrational excitation of the HCl bond in the pre-reactive F HCl complex. Such open-shell species provide a challenge for quantum dynamical calculations due to the need to take into account multiple potential energy surfaces to accurately describe the system. A three-dimensional, fully-coupled potential energy surface has been constructed based on electronic energies calculated at the multireference configuration interaction+Davidson correction (MRCI+Q) level of theory with an aug-cc-pVnZ ( ) basis.a Spin orbit calculations have also been included. b Here we present the results of time-dependent quantum wave packet calculations on the asymmetric hydrogen-transfer reaction of F( P) + HCl. In these calculations, the reaction is initiated by vibrationally exciting the HCl stretching motion in the pre-reactive F HCl complex. The wave packet is propagated on the coupled potential energy surfaces. Product state distributions were calculated for reactions initiated in the first three vibrationally excited states of HCl, 1 . a M. b M. P. Deskevich, M. Y. Hayes, K. Takahashi, R. T. Skodje, and D. J. Nesbitt J. Chem. Phys. 124(22) 224303 (2006) P. Deskevich and D. J. Nesbitt private communication(2007) 188 WF11 PROBING THE REACTION PATH OF 15 min 4:40 CH + H CH CH + H AND ISOTOPOLOGUES CHARLOTTE E. HINKLE, ANNE B. McCOY, Department of Chemistry, The Ohio State University, Columbus, OH 43210. Protonated methane has long been of interest to astrochemists due to its presumed importance as a reaction intermediate in the reaction involving CH + HD within the interstellar medium. Within the interstellar medium there is a nonstatistical H/D isotopic abundance observed for isotopologues of CH . While classical trajectory calculations have been performed into the fragments, CH + H , CH D + H and CH + HDa , these calculations do not dissociating CH and CH D account for a large portion of the available energy being tied up in the zero point energy of the reactants and products. b Earlier work in our group on CH D showed the deuterium atoms were localized to the CH group, rather than the H moiety. Classical calculations fail to account for this observed localization, instead showing full delocalization of D between both CH and H . With a quantum mechanical treatment, the energetics and wave functions will depend on which asymptotic channel is chosen, while in the classical treatment, these channels will be energetically equivalent. By performing Diffusion Monte Carlo simulations in Jacobi coordinates, we can constrain the distance between the CH and H subunits. Using this technique we have evaluated a one-dimensional reaction potential that includes the full anharmonic zero point energy in the remaining degrees of freedom and can determine how energetics of this reaction change upon partial deuteration of CH or H . We have also evaluated the probability amplitude associated with the wave functions that are obtained in the DMC simulations at various values of the reaction coordinate. a Z. b A. Jin, B. J. Braams, J. M. Bowman, J. Phys. Chem. A 110, 1569 (2006). B. McCoy, B. J. Braams, A. Brown, X. Huang., Z. Jin, J. M. Bowman, J. Phys. Chem. A 108, 4991 (2004). WF12 INTRAMOLECULAR VIBRATIONAL ENERGY REDISTRIBUTION IN THE REACTION H + CO H + HCO /HOC 15 min 4:57 TSUNEO HIRANO, Department of Chemistry, Faculty of Science, Ochanomizu University, Tokyo 112-8610, Japan; HUI LI, ROBERT J. LE ROY, and TAKAYOSHI AMANO, Department of Chemistry, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada. Observations of the rotational lines of HCO produced in an extended negative glow discharge revealed high vibrational temperatures for the stretching vibrational modes, and non-thermal population distributions among the different > levels of excited bending vibrational states. a b These results provide critical tests of our understanding of the dynamics and intramolecular vibrational energy redistribution (IVR) in this reaction process. The IVR in the HNC HCN isomerization reactionc has been studied previously by ab initio direct dynamics and vibration-mapping d methods. An extension of the method used for the HNC/HCN isomerization reaction yields a new procedure for studying “IVR in reactions” which is applied to HCO /HOC production in the H + CO reaction, as described by the five-dimensional potential energy surface and pathways for this reaction reported recently by Li et al. e Dynamics calculations have been performed for “co-linear configuration” reactions in which H approaches the C end of CO with a translational temperature of 20 K (a typical kinetic temperature of dark clouds) or 330 K (a typical translational temperature for ions in a glow discharge). As H approaches CO with the lower-temperature translational energy, the hopping of H to the CO moiety to form HCO occurs over a period of about 100 fs, and the H–C stretching mode of the product HCO is highly excited. This excitation can relax within the same vibrational ladder and/or be transferred to the bending mode through anharmonic coupling. Details of direct dynamics calculations for this process will be reported. a T. Hirao, S. Yu, and T. Amano,J. Chem. Phys., 127,074301 (2007). Hirao, S. Yu, and T. Amano, J. Mol. Spectrosc., 248, 26 (2008). c Y. Kumeda, Y. Minami, K. Takano, T. Taketsugu, and T. Hirano, J. Mol. Struct. (THEOCHEM), 458, 285 (1999) d T. Hirano, T. Taketsugu, and Y. Kurita, J. Phys. Chem., 98, 6936 (1994). e H. Li, T. Hirano, T. Amano, and R.J. Le Roy, J. Chem. Phys., 129, 244306 (2008). b T. 189 WF13 15 min 5:14 MEASUREMENT OF THE VIBRATIONAL POPULATION DISTRIBUTION OF BARIUM SULFIDE SEEDED IN AN ARGON SUPERSONIC EXPANSION FOLLOWING PRODUCTION THROUGH THE REACTION OF LASER ABLATED BARIUM WITH CARBONYL SULFIDE CHRIS T. DEWBERRY, GARRY S. GRUBBS II, KERRY C. ETCHISON, and STEPHEN A. COOKE, The Department of Chemistry, University of North Texas, P.O. Box 305070, Denton, TX, 76203-5070. A chirped pulsed Fourier transform microwave spectrometer has been used to examine the reaction products of laser ablated barium with carbony sulfide. We find the & = 2 - 1, = 0, transition for Ba S, at 12370.1938(20) MHz, is 8.94 times as intense as the same transition for the Ba S isotopologue, at 12404.4384(20) MHz. This is in reasonable agreement to the ratio of the natural abundances of Ba : Ba = 9.12 : 1. Given this agreement we are able to use the Ba S & = 2 - 1 spectra to qualitatively monitor vibrational populations of BaS in the supersonic expansion following the ablation event. We are able to see the & = 2 - 1 rotational transition for the parent isotopologue in up to the = 6 vibrational level. The ablation conditions have been altered, i.e. Nd:YAG laser power, laser pulse duration, backing gas pressure, OCS (H S) concentration, and carrier gas (Ar, Ne, 30:70 He:Ne and pure He), and the effects on the BaS spectrum monitored. We can also monitor OCS depletion due to the laser event by running the experiment with the laser on then off. Along side these experiments we have also recorded the nuclear quadrupole coupling constants, 0+A ( Ba) and 0+A ( Ba) in BaS and performed a multi-isotopomer fit to the experimental data. Results will be presented. WF14 DC SLICED PHOTODISSOCIATION STUDY OF OZONE AT 226NM 10 min 5:31 PRASHANT. CHANDRA. SINGH, L. SHEN, A. G. SUITS, Department of Chemistry, Wayne State University, Detroit, MI 48201; G. C. MCBANE, Grand Valley State University, Allendale, MI 49401; R. SCHINKE, Max Planck Institute for Dynamics and Self-organization, D-37073 Gottingen, Germany. Ozone photodissociation below 234 nm gives rise to a bimodal recoil velocity dstribution in the minor channel giving O ( P ) as a product, and the source of this bimodality has so far eluded definitive explanation. It has long been asribed to coincident production of highly vibraitonally excited O possibly through some distinct intersection seam of the relevant potential energy surfaces, but extensive theoretical effort has failed to find a plausible pathway for this. We have used the DC sliced imaging method to reinvestigate the product O ( P ) of ozone photodissociation at 226nm at very high velocity resolution. The experimental results are focused exclusively on the slow component for the O ( P ) fragments formed in the photodissociation of ozone at the 226.06 nm for J=1 and 225.65 nm for J=2. The total translational energy distributios for the slow components show two distinct peaks that are coincident, within 0.01 eV, with the onset of v=0 and 1 of the state of O as a cofragment. Furthermore, trajectory calculations show that, at this excitation energy, the region of the ozone ”B” state that correlates with the Herzberg states of oxygen is accessible, and a fraction of trajectories reach this intersection region. These combined experimental and theoretical investigations provide compelling evidence that the origin of the slow peaks in the O( P ) product of ozone dissociation below 234 nm is the channel yielding the state of O as a coproduct. 190 WG. INFRARED/RAMAN WEDNESDAY, JUNE 24, 2009 – 1:30 PM Room: 170 MATH ANNEX Chair: ROBERT McKELLAR, National Research Council of Canada, Ottawa, ON, Canada WG01 STATUS ON THE GLOBAL VIBRATION-ROTATION MODEL IN ACETYLENE 15 min 1:30 B. AMYAY, M. HERMAN, Service de Chimie quantique et Photophysique CP160/09, Facult é des Sciences, Université Libre de Bruxelles (U.L.B.), Av. Roosevelt, 50, B-1050, Bruxelles, Belgium; A. FAYT, Laboratoire de Spectroscopie Moléculaire, Université Catholique de Louvain, Chemin du Cyclotron, 2, B-1348 LouvainLa-Neuve, Belgium. We have developed a global model to deal with all vibration-rotation levels in acetylene up to high vibrational excitation energy, typically up to 9000 wavenumbers. It has been applied to a number of isotopologues, considering all known vibration-rotation lines published in the literature, for various purposes such as line assignment a and astrophysical applications b . Coriolis interaction is now systematically being introduced in the model. Recent results concerning the analysis of hot emission FTIR spectra recorded around 3 microns by R. Georges et al. at the University of Rennes (France) and of CW-CRDS spectra recorded around 1.5 microns by A. Campargue et al. at the University of Grenoble (France) will help illustrate the role of this vibration-rotation coupling in the global polyad scheme. a S. b A. Robert, M. Herman, A. Fayt, A. Campargue, S. Kassi, A. Liu, L. Wang, G. Di Lonardo, and L. Fusina, Mol. Phys., 106, 2581 (2008). Jolly, Y. Benilan, E. Cané, L. Fusina, F. Tamassia, A. Fayt, S. Robert, and M. Herman, J.Q.S.R.T., 109, 2846 (2008). WG02 15 min 1:47 EXPLORING THE VIBRATIONAL STRUCTURE OF THE VINYLIDENE ANION USING ARGON PREDISSOCIATION SPECTROSCOPY KRISTIN J. BREEN, HELEN K. GERARDI, GEORGE H. GARDENIER, TIMOTHY L. GUASCO, JENNIFER E. LAASER, ERIC G. DIKEN, GARY H. WEDDLE and MARK A. JOHNSON, Sterling Chemistry Laboratory, Yale Universtiy, PO Box 208107, New Haven, CT 06520. We report Ar-mediated vibrational spectra of the vinylidene anion, a relevant intermediate in various chemical processes, and its fully deuterated form in order to characterize the vibrational energy levels present in this species. Identification of the C-H asymmetric and symmetric stretching frequencies was made and confirmed by the deuterium isotope shift. This information could then be used to clarify the origin of two higher energy peaks around 4000 and 4200 cm in the light isotope, which occur quite close to the photodetachment threshold. Preliminary analysis indicates their assignment to combination bands involving excitation of the C=C stretch along with the C-H fundamentals. The work was then extended to include the NNO molecule as a messenger species. 191 WG03 15 min 2:04 UNRAVELLING THE MECHANISM OF RESONANT TWO-PHOTON PHOTODETACHMENT OF THE VINYLIDENE ANION, H C=C , USING VELOCITY-MAP PHOTOELECTRON IMAGING H. K. GERARDI, K. J. BREEN, G. H. GARDENIER, T. L. GUASCO, J. E. LAASER, G. H. WEDDLE, and M. A. JOHNSON, Sterling Chemistry Laboratory, Yale University, PO Box 208107, New Haven, CT 06520. Vinylidene, an isomer of acetylene and the simplest unsaturated carbene, has been studied extensively due to its role as a possible intermediate in a wide range of important chemical reactions. The neutral form of vinylidene is an extremely short-lived species and therefore information about its structure and potential energy surface may be gained through the study of its stable anionic form. Using velocity-map photoelectron imaging to investigate the behavior of the anion, we observe electron loss with excitation energies lower than the established electron adiabatic detachment energy (ADE). An in-depth analysis of the velocity-map images and corresponding photoelectron spectra taken at various energies within the C-H stretching region as well as at energies around the ADE provide plausible explanations for the observed behavior. The study also reveals interesting angular distributions specific to certain vibrational modes that are not trivial to understand at this point. WG04 15 min 2:21 DETECTION AND ANALYSIS OF ROTATIONALLY RESOLVED TORSIONAL SPLITTINGS IN PHENOL (C H OH): THE HIGH RESOLUTION FTIR SPECTRUM OF PHENOL BETWEEN 600 AND 1300 CM SIEGHARD ALBERT, MARTIN QUACK, PHYSICAL CHEMISTRY, ETH Z ÜRICH, CH-8093 ZÜRICH, SWITZERLAND. One of the great challenges of high resolution infrared spectroscopy is to understand the rovibrationally resolved spectra and dynamics of large molecules involving numerous degrees of freedom and large amplitude motions like bending, torsion or inversion modes a . Complicated resonance networks can be built up through the coupling of such modes and the energy flow can be studied upon excitation bc . Excellent examples of the study of such phenomena are the FTIR spectra of aromatic systems which can now be rovibrationally resolved using state-of-the-art technology d. As a benchmark molecule we shall discuss phenol. Its vibrational spectrum has already been assigned at low resolution e and its photodissociation has been studied recently f . Its rotationally resolved infrared spectrum has now been recorded in the range 600–1300 cm with our Bruker ZP2001 spectrometer with a resolution of better than 0.001 cm . This spectrum was used in an analysis of the out-of-plane modes ( = 687.00544 cm ) and ( = 881.70033 cm ). Here, no torsional splittings or resonances were observed, as opposed to the spectrum of the -type bands (OH-sensitive), (OH-sensitive), (CO-stretch), ) (OH-bend) and the combination bend B (CH-bend + torsion). We will discuss the & -dependent doublets with splittings ranging from 0.01 to 0.04 cm observed in the rovibrational spectra, and will present an analysis of the combination band B with band centers of the two torsional components = 1198.24163 cm and = 1198.20114 cm . A comparison between the phenol and fluorobenzene spectra will also be presented. a S. Albert and M. Quack, ChemPhysChem 2007, 8, 1271, M. Quack, J. Mol. Struct. 1995, 347, 245. R. Dübal and M. Quack, J. Chem. Phys. 1984, 81(9), 3779. M. Quack, Ann. Rev. Phys. Chem. 1990, 41, 839. c S. Albert, M. Winnewisser and B.P. Winnewisser, Ber. Bunsenges. Phys. Chem. 1996, 100, 1876, S. Albert, M. Winnewisser and B.P. Winnewisser, Ber. Bunsenges. Phys. Chem. 1997, 101, 1165. d S. Albert, K.K. Albert and M. Quack, Trends in Optics and Photonics 2003, 84, 177. e H.D. Bist, J. Brand and D.R. Willams, J. Mol. Spectrosc. 1967, 24, 402. f M.L. Hause, Y.H. Yoon, A.S. Case and F. Crim, J. Chem. Phys. 2008, 128, 104307. b H. 192 WG05 15 min 2:38 SH-STRETCHING INTENSITIES AND INTRAMOLECULAR HYDROGEN BONDING IN ALKANETHIOLS B. J. MILLER, J. R. LANE, A. H. SODERGREN, H. G. KJAERGAARD, Department of Chemistry, University of Otago, P.O. Box 56, Dunedin, New Zealand; M. E. DUNN, AND V. VAIDA, Department of Chemistry and Biochemistry and CIRES, University of Colorado, Campus Box 215, Boulder, CO 80309. The SH-stretching overtone transitions of tert-butylthiol and ethanethiol are observed using FT-IR, NIR and photoacoustic spectroscopies. The intensities of these are compared with OH-stretching overtones from the corresponding alcohols. We explain the paucity of SH-stretching intensity using an anharmonic oscillator local mode model. SH- and OH-stretching overtone spectra of 1,2-ethanedithiol and 2-mercaptoethanol are recorded to observe the different effects that hydrogen bonding involving SH - - - S, SH - - - O and OH - - - S have on the spectra. We discuss these effects with the help of high level ab initio calculations. WG06 10 min 2:55 INVESTIGATION OF MEMBRANE PEPTIDES BY TWO-DIMENSIONAL INFRARED SPECTROSCOPY EMILY ANN BLANCO, MARTIN T. ZANNI, Department of Chemistry, University of Wisconsin Madison, 1101 University Ave, Madison, WI 53706. Two-dimensional infrared spectroscopy (2D IR) is a useful tool for studying the structure of membrane peptides. Isotope labeling individual amino acids with 13C=18O decouples the isotope labeled amide I from the other amide I modes in the peptide. Work has been done on both the M2 ion channel and ovispirin antimicrobial peptide, studying the diagonal linewidths of the isotope labeled amide I. The diagonal linewidth of the isotope labeled amide I gives information about the local environment of that residue, which in turn gives structural information about the membrane peptide. WG07 15 min 3:07 GAS PHASE RAMAN SPECTRA OF BUTADIENE AND BUTADIENE-d AND THE INTERNAL ROTATION POTENTIAL ENERGY FUNCTION PRAVEENKUMAR BOOPALACHANDRAN, JAAN LAANE, Dept. of Chemistry, Texas A&M University, College Station, TX 77843-3255; and NORMAN C. CRAIG, Dept. of Chemistry & Biochemistry, Oberlin College, Oberlin, OH 44074. The Raman spectrum of butadiene has been previously reported by Carreira a and by Engeln and co-workers b . Both studies reported a series of bands corresponding to double quantum jumps of , the internal rotation vibration, of the trans rotamer. Both studies also reported weaker bands assigned to the higher energy conformer. Carriera assigned these to the cis form while Engeln assigned them to the gauche form. Recent high level calculations by Feller and Craig c also assign the higher energy form as gauche. In the present study we report the gas phase Raman spectrum of butadiene and its d isotopomer at both Æ C and Æ C. Several new spectral features in the 330 to 210 cm region were observed and the effect of heating on the band intensities was studied. In addition, combination bands were observed in the 630 to 690 cm ( + ) and 1130 to 1180 cm ( + ) regions. A periodic potential energy function with V , V , V , V , and V terms was utilized to fit the data. This function was compared to the results from previous work and to the theoretical calculation. a L. Carreira, J. Phys. Chem. 62, 3851 (1975). Engeln, D. Consalvo, and J. Reuss, J. Chem. Phys. 160, 427 (1992). c D. Feller and N. C. Craig, J. Phys. Chem. 113, 1601 (2009). b R. 193 WG08 10 min 3:24 SECONDARY PERIODICITY IN THE STRUCTURAL AND VIBRATIONAL CHARACTERISTICS OF 3,3DIMETHYLCYCLOPROPENES DI- AND MONOSUBSTITUTED BY –X (X = C, Si, Ge, Sn, Pb) Yu. N. PANCHENKO, A. V. ABRAMENKOV, Div. of Phys. Chem., Dept. of Chem., M. V. Lomonosov Moscow State University, Moscow 119992, Russian Federation; and G. R. DE MAR É, Université Libre de Bruxelles, Faculté des Sciences, Service de Chimie Quantique et de Photophysique, CP160/09, 50 av. F. D. Roosevelt, B1050 Brussels, Belgium. The regularities of changes in the structural parameters and vibrational wavenumbers have been traced for certain moieties of the title compounds. The optimized geometrical parameters and the force fields of disubstituted 3,3-dimethylcyclopropenesa and monosubstituted 3,3-dimethylcyclopropenes b were determined at the HF/3-21G* and DDAll levels, respectively. The choice of these theoretical levels was brought about by peculiarities of GAUSSIAN 03 suite of programs for Sn and Pb atoms. The theoretical vibrational wavenumbers were calculated from the corresponding scaled force fields. The regularities obtained in the form of the zigzag lines are analogous to regularities that are characteristic to the atoms of the 14 (IVA) group of the Mendeleyev Periodic Table. This is known as the secondary periodicity phenomenon. a Yu. b G. N. Panchenko, G. R. De Maré, A. V. Abramenkov, and A. de Meijere, Spectrochim. Acta 65A, 575 (2006). R. De Maré, Yu. N. Panchenko, and A. V. Abramenkov, Spectrochim. Acta 67A, 1094 (2007). Intermission WG09 15 min 3:50 DENSITY FUNCTIONAL THEORY STUDY ON MOLECULAR STRUCTURE AND VIBRATIONAL SPECTRA OF 4-AMINO-1-METHYLBENZENE M. KUMRU, T. BARDAKCI, L. SARI, Fatih University, Faculty of Arts and Sciences, Department of Physics, 34500 Bykekmece, Istanbul, TURKEY. We have discussed the applicability limits of HF, MP2 and DFT-B3LYP methods on 4-amino-1-methylbenzene in our previous work [1]. We have found the DFT-B3LYP method very promising for vibrational spectral analyses. In this study, we extend DFT calculations with different basis sets for more appropriateness to exprimental results. The optimized molecular structures, vibrational frequencies and coresponding vibrational assigments of 4-amino-1-methylbenzene have been obtained from the DFT-B3LYP, DFT-B3PW91 and DFT-PBEPBE methods implementing the 6-311G+** and aug-ccPVQZ basis sets. Scale factors, which bring computational frequencies in closer agreement with the experimental data, have been calculated for predominant vibrational motions of the normal modes at each level considered. All observed harmonic IR and Raman bands of 4-amino-1-methylbenzene have been assigned in the frameworks of the calculations. The comparison of calculations with FT-IR and FT-Raman spectra of 4-amino-1-methylbenzene have been carried out. We are planing to extend this work to the transition metal complexes in the form of MX2L2 [M: Transition metals e.g. Mn(II), Co(II) and Ni(II) . . . ; X : Halogens e.g Cl, Br, I, L: 4-amino-1-methylbenzene] 1. A. Altun, K. Golcuk, M. Kumru, ”Structure and vibrational spectra of p-methylaniline: Hartree-Fock, MP2 and density functional theory studies”, JOURNAL OF MOLECULAR STRUCTURE-THEOCHEM 637: 155-169 OCT 3 2003 194 WG10 15 min 4:07 THE r STRUCTURAL PARAMETERS OF EQUATORIAL BROMOCYCLOBUTANE, CONFORMATIONAL STABILITY FROM TEMPERATURE DEPENDENT INFRARED SPECTRA OF XENON SOLUTIONS, AND VIBRATIONAL ASSIGNMENTS ARINDAM GANGULY, JOSHUA J. KLAASSEN, TODOR K. GOUNEV, JAMES R. DURIG, DEPARTMENT OF CHEMISTRY, UNIVERSITY OF MISSOURI-KANSAS CITY, KANSAS CITY, MO 64110,USA; GAMIL A. GUIRGIS, DEPARTMENT OF CHEMISTRY AND BIOCHEMISTRY, COLLEGE OF CHARLESTON, CHARLESTON, SC 29424, USA. Variable temperature (-55 to Æ) studies of the infrared spectra (4000-400 cm ) of bromocyclobutane, c-C H Br dissolved in liquid xenon have been carried out. The infrared spectrum (4000-100 cm ) of the gas has also been recorded. The enthalpy difference between the more stable equatorial conformer and the axial form, has been determined to be 372 . This experimental value of H is much lower than the average MP2(full) ab initio predicted value of 521 34 cm 87 cm . The percentage of the axial conformer present at ambient temperature is estimated to be 14 1+. By utilizing previously reported microwave rotational constants for the equatorial conformer combined with ab initio MP2(full)/6311+G(d,p) predicted structural values, adjusted r parameters have been obtained. The determined heavy atom structural ˚ ) C -Br = 1.942(3), C -C = 1.541(5), C -C = 1.552(3) ˚ and angles parameters for this conformer are with distances( in degrees C C Br = 118.4(5), C C C = 89.7(5), C C C = 86.8(5), C C C = 88.9(5) and B C C C C = 29.8 Æ. The results will be discussed and compared to the corresponding properties of some similar molecules. WG11 15 min 4:24 MEASUREMENT OF ROTATIONAL STATE-TO-STATE RELAXATION COEFFICIENTS BY RAMAN-RAMAN DOUBLE RESONANCE. APPLICATION TO SELF-COLLISIONS IN ACETYLENE. J. L. DOMENECH, R. Z. MARTINEZ, and D. BERMEJO, Instituto de Estructura de la Materia (CSIC), Serrano 123, E-28006 Madrid, SPAIN. We have developed a technique for the measurement of state-to-state rotational relaxation rates due to collisions in the gas phase. A single J state of the 1 vibrational level of acetylene is populated by a Stimulated Raman process. After a variable delay of a few ns we record high resolution ( 0.003 cm ) spectra of the Q-branch of the 1 v transition by a second Stimulated Raman process. The relative intensities of the lines of this Q-branch, recorded as a function of the the initially pumped J level and the number of collisions between the pump and probe stages (delay pressure product), allows us to obtain a set of state-to-state energy transfer coefficients by fitting the evolution of the observed populations to that predicted by a master equation with adjustable coefficients. The experimental details and first results for odd-J levels of acetylene at 150 K will be presented. WG12 RAMAN SPECTRAL SIGNATURES AS CONFORMATIONAL PROBES OF BIOMOLECULES 10 min 4:41 AMIR GOLAN, NITZAN MAYORKAS, SALMAN ROSENWAKS, ILANA BAR, Department of Physics, Ben-Gurion University, Beer Sheva 84105, Israel. A first application of ionization-loss stimulated Raman spectroscopy (ILSRS) for monitoring the spectral features of four conformers of a gas phase neurotransmitter (2-phenylethylamine) is reported. The Raman spectra of the conformers show bands that uniquely identify the conformational structure of the molecule and are well matched by density functional theory calculations. The measurement of spectral signatures by ILSRS in an extended spectral range, with a relatively convenient laser source, is extremely important, allowing enhanced accessibility to intra- and inter-molecular forces, which are significant in biological structure and activity. 195 WG13 15 min 4:53 CONFORMATION-SPECIFIC AND MASS-RESOLVED, INFRARED-POPULATION TRANSFER SPECTROSCOPY OF THE MODEL -PEPTIDE Ac- -hPhe-NHMe: EVIDENCE FOR THE PRESENCE OF INTRAMOLECULAR AMIDE-AMIDE STACKING INTERACTIONS. WILLIAM H. JAMES III, EVAN G. BUCHANAN, CHRISTIAN W. M ÜLLER , and TIMOTHY S. ZWIER, Department of Chemistry, Purdue University, West Lafayette, IN 47907; MICHAEL G. D. NIX, School of Chemistry, University of Bristol, Bristol BS8 1TS, UK; LI GUO, and SAMUEL H. GELLMAN, Department of Chemistry, University of Wisconsin-Madison, Madison, WI 53706. Recently, double resonance spectroscopy has been utilized to elucidate the conformational preferences of natural a and syntheticb peptide mimetics. These studies demonstrated the power of double resonance methods and highlighted the ability of even short peptide mimetics to form a variety of intramolecular hydrogen bonded architectures. Currently, we have undertaken a detailed study of a model -peptide using double resonance spectroscopy. Conformation-specific IR spectra in the amide NH and amide I stretch spectral regions of Ac- -hPhe-NHMe provide evidence for three unique conformational isomers in a jet-cooled environment. The results of DFT and MP2 calculations will be presented as a basis for assignment of the experimentally resolved conformers. Two conformers form nine atom, intramolecular hydrogen bonded rings, which differ by the position of the aromatic ring relative to the peptide backbone. The third conformer does not contain intramolecular hydrogen bonding, but forms an intramolecular, amide-amide stacking structural motif, which when analyzed with the quantum theory of Atoms In Molecules is shown to contain an interaction between the carbon atom of the acetylated N-terminal amide and the nitrogen atom of the methylated C-terminal amide. In an effort to quantitatively assess the competition between hydrogen bonded and amide-amide stacked conformers, mass-resolved, infrared-population transfer spectroscopy was developed, where the IR and molecular beams are counter-propagated allowing for a re-cooling step prior to detection via resonant two-photon ionization spectroscopy. Using this method the fractional abundances of each conformer were experimentally determined. a W. b E. Chin, F. Piuzzi, I. Dimicoli, and M. Mons, PCCP, 2006, 8, 1033. E. Baquero, W. H. James III, S. H. Choi, S. H. Gellman, and T. S. Zwier, J. Am. Chem. Soc., 2008, 130, 4784. WG14 15 min 5:10 CALCULATION OF THE MOLAR VOLUME AS A FUNCTION OF PRESSURE FROM THE RAMAN FREQUENCIES IN NH Br H. YURTSEVEN, Department of Physics, Middle East Technical University, 06531 Ankara, TURKEY. The molar volume is calculated as a function of pressure using the observed Raman frequencies of the TA (57 cm ) and TO (140 cm) modes of NH Br in the disordered phase II. This calculation is performed through the mode Grüneisen parameter which is taken as a constant for each mode studied throughout the phase II of this crystal. Measurements of the lattice parameter (molar volume) can be performed to examine our calculations from the Raman frequencies studied here for NH Br. 196 WH. MINI-SYMPOSIUM: FIR/THz AIR/SPACE MISSIONS WEDNESDAY, JUNE 24, 2009 – 1:30 PM Room: 1000 McPHERSON LAB Chair: JOHN C. PEARSON, Jet Propulsion Laboratory, Pasadena, California WH01 INVITED TALK 30 min 1:30 ASTRONOMICAL AND ATMOSPHERIC SPECTROSCOPY IN THE SMM/THz: EXPERIMENTS, ANALYSIS, AND CATALOGS. FRANK C. DE LUCIA, Department of Physics, 191 W. Woodruff Ave., Ohio State University, Columbus, OH 43210 USA. For many years the needs of the astronomical and atmospheric science communities have directly or indirectly motivated much of the work at this symposium. Interestingly, the power and sophistication of the field instruments have grown at such a rate that the needs for laboratory data seem to be diverging rather than converging. The central role played by catalogs will be discussed, as well as their impact on the spectroscopic community. WH02 15 min 2:05 INDIRECT TERAHERTZ SPECTROSCOPY OF MOLECULAR IONS USING HIGHLY ACCURATE AND PRECISE MID-IR SPECTROSCOPYa ANDREW A. MILLS, KYLE B. FORD, HOLGER KRECKEL, MANORI PERERA, KYLE N. CRABTREE, Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, IL 61801; BENJAMIN J. McCALL, Departments of Chemistry and Astronomy, University of Illinois at Urbana-Champaign, Urbana, IL 61801. With the advent of Herschel and SOFIA, laboratory methods capable of providing molecular rest frequencies in the terahertz and sub-millimeter regime are increasingly important. As of yet, it has been difficult to perform spectroscopy in this wavelength region due to the limited availability of radiation sources, optics, and detectors. Our goal is to provide accurate THz rest frequencies for molecular ions by combining previously recorded microwave transitions with combination differences obtained from high precision mid-IR spectroscopy. We are constructing a Sensitive Resolved Ion Beam Spectroscopy setup which will harness the benefits of kinematic compression in a molecular ion beam to enable very high resolution spectroscopy. This ion beam is interrogated by continuous-wave cavity ringdown spectroscopy using a homemade widely tunable difference frequency laser that utilizes two near-IR lasers and a periodically-poled lithium niobate crystal. Here, we report our efforts to optimize our ion beam spectrometer and to perform high-precision and high-accuracy frequency measurements using an optical frequency comb. a This work is supported by the NASA APRA Laboratory Astrophysics program. 197 WH03 15 min 2:22 CATION FAR INFRARED VIBRATIONAL SPECTROSCOPY OF POLYCYCLIC AROMATIC HYDROCARBONS W. KONG, J. ZHANG, and F. HAN, Department of Chemistry, Oregon State University, Corvallis, OR 97331. The far infrared (FIR) region is crucial for spectroscopic investigations because of the existence of skeletal modes of moderately sized molecules. However, our knowledge of FIR modes is significantly lacking, largely due to the limited availability of light sources and detectors in this spectral region. The technique pulsed field ionization zero kinetic energy electron spectroscopy (PFI-ZEKE) is ideal for studies of FIR spectroscopy. This is because the low internal energy of the cation associated with the skeletal modes is particularly beneficial for the stability of the corresponding Rydberg states. In this work, we report our effort in studies of FIR spectroscopy of cationic polycyclic aromatic hydrocarbons (PAH). Using laser desorption, we can vaporize the non-volatile PAH for gas phase spectroscopy. To ensure the particle density and therefore the critical ion density in prolonging the lifetime of Rydberg electrons, we have used a chamber-in-a-chamber design and significantly shortened the distance between the desorption region and the detection region. From our studies of catacondensed PAHs, we have observed the emergence of the flexible waving modes with the increasing length of the molecular ribbon. Pericondensed PAHs, on the other hand, have shown significant out of plane IR active transitions. The planarity of the molecular frame is therefore a question of debate. The FIR modes are also interesting for another reason: they are also telltales of the precision of modern computational packages. The combination of experimental and theoretical studies will help with the identification of the chemical composition of the interstellar medium. This effort therefore directly serves the missions of the Spitzer Space Observatory and more importantly, the missions of the Herschel Space Observatory. WH04 15 min 2:39 NUMERICAL AND EXPERIMENTAL ASPECTS OF DATA ACQUISITION AND PROCESSING IN APPLICATION TO TEMPERATURE RESOLVED 3-D SUB-MILLIMETER SPECTROSCOPY FOR ASTROPHYSICS AND SPECTRAL ASSIGNMENT. IVAN R. MEDVEDEV, SARAH M. FORTMAN, CHRISTOPHER F. NEESE, and FRANK C. DE LUCIA, Department of Physics, 191 W. Woodruff Ave., Ohio State University, Columbus, OH 43210 USA. Experimental determination of the lower state energy for every transition in molecular spectra, made possible by temperature resolved 3-D spectroscopy, opens new frontiers in our ability to predict molecular spectra over a wide range of temperatures and to assign rotational spectra in many vibrational states. Our improved collisional cooling cell design extends temperature coverage of this technique to 77 K. This enhances our ability to simulate molecular spectra at temperatures of astronomical relevance. We are reporting on experimental and numerical aspects of dealing with exceptionally high information content of these spectra. New data reduction algorithms allow us to process this data in timely fashion in an attempt to make them available to astronomical community. WH05 15 min 2:56 TEMPERATURE RESOLVED 3-D SUBMILLIMETER SPECTROSCOPY OF ASTRONOMICAL ‘WEEDs’. SARAH M. FORTMAN, IVAN R. MEDVEDEV, CHRISTOPHER F. NEESE, and FRANK C. DE LUCIA, Department of Physics, 191 W. Woodruff Ave., Ohio State University, Columbus, OH 43210 USA. We have previously reported on the experimental spectroscopic approach that makes possible the calculation of lower state energy levels and transition strengths without the need for spectral assignment a . Analysis of the temperature dependent measurements significantly improves the estimate of the lower state energy, recovered by division of temperature dependent spectral intensities. Also, this approach provides results both in the standard astronomical catalog form (frequency, line strength, lower state energy) and as experimental temperature dependent spectra. We are reporting on temperature resolved 3-D spectroscopy of ethyl cyanide — a well known astronomical ‘weed’. a ”An experimental approach to the prediction of complete millimeter and submillimeter spectra at astrophysical temperatures: Applications to confusion-limited astrophysical observations,” I. R. Medvedev and F. C. De Lucia, Ap. J. 656, 621-628 (2007). 198 WH06 15 min 3:13 GENERATION OF WIDELY TUNABLE FOURIER-TRANSFORM-LIMITED PULSED TERAHERTZ RADIATION USING NARROWBAND NEAR-INFRARED LASER RADIATION JINJUN LIU, CHRISTA HAASE, and FRÉDÉRIC MERKT, Laboratorium f ür Physikalische Chemie, ETHZürich, 8093 Z ürich, Switzerland. Widely tunable, Fourier-transform-limited pulses of terahertz (THz) radiation have been generated by optical frequency deference using (i) crystals of the highly nonlinear organic salt 4- , -dimethylamino-4 - -methyl stilbazolium tosylate (DAST), (ii) zinc telluride (ZnTe) crystals, and (iii) gallium phosphide (GaP) crystals. Outputs from two narrowband ( 51 MHz, 4 800 nm) cw titanium-doped sapphire (Ti:Sa) ring lasers with a well-controlled frequency difference were shaped into pulses using acousto-optic modulators, coupled into an optical fiber, pulse amplified in Nd:YAG-pumped Ti:Sa crystals and used as optical sources to pump the THz nonlinear crystals. The THz radiation was detected over a broad frequency range and its bandwidth was determined to be 10 MHz. Absorption spectra of gas phase molecules including HF and OCS using the THz source will be presented. Intermission WH07 INVITED TALK 30 min 3:45 THE COLOGNE DATABASE FOR MOLECULAR SPECTROSCOPY, CDMS, IN TIMES OF HERSCHEL, SOFIA, AND ALMA HOLGER S. P. MÜLLER, JÜRGEN STUTZKI, STEPHAN SCHLEMMER, I. Physikalisches Institut, Universität zu Köln, Zülpicher Str. 77, 50937 K öln, Germany. The CDMS provides in its catalog section atomic and molecular line lists for species that have been or may be observed in space by radio astronomical means. abc The line list of each molecule is gathered in an individual entry; minor isotopologs have separate entries, and the same applies to excited vibrational states with the exception of some diatomic molecules. With 5 to 10 new or updated entries each month, the CDMS catalog has been growing rapidly over the past 10 years: since February 2009, there have been more than 500 entries in the CDMS with many more entries to be created. Entries are generated from fitting (mostly) laboratory data to accepted Hamiltonian models. Despite many dedicated laboratory spectroscopic investigations in recent years, accurate data is still lacking frequently in particular at higher frequencies, for minor isotopic species, for excited vibrational states, or for somewhat larger molecules. While high frequency data are of special concern for the Herschel satellite, scheduled to be launched in mid-April 2009, or for the Stratospheric Observatory For Infrared Astronomy (SOFIA), the remaining issues mentioned above are important especially for telecope arrays such as the Atacama Large Millimeter Array (ALMA). The main features of the CDMS catalog will be described, including recent developments concerning new entries as well as available and planned features. In particular, we will discuss issues relevant for generating a consolidated database that also takes into account information from other databases. Attention will be given to laboratory spectroscopic needs for missions such as Herschel and SOFIA on one hand and for ALMA, the Expanded Very Large Array (EVLA), and other facilities on the other, both, in terms of general aspects and in terms of specific examples. Selected contributions from the Cologne spectroscopy laboratories to address these needs will be presented. a H. S. P. Müller, S. Thorwirth, D. A. Roth, G. Winnewisser, Astron. Astrophys. 370 (2001) L49 L52. Müller, F. Schlöder, J. Stutzki, G. Winnewisser, J. Mol. Struct. 742 (2005) 215 227. c web-page: http://www.astro.uni-koeln.de/cdms/. b H. S. P. 199 WH08 15 min 4:20 UPDATE FOR USERS OF THE METHANOL DATABASE: RECENT IMPROVEMENTS, REMAINING PROBLEMS, AND MORE COMPLICATED REGIONS LI-HONG XU, Department of Physics and Centre for Laser, Atomic, and Molecular Sciences, University of New Brunswick, Saint John, NB E2L 4L5, Canada; J.C. PEARSON, B.J. DROUIN, Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA USA 91109; J.T. HOUGEN, Optical Technology Division, National Institute of Standards and Technology, Gaitherburg, MD 20899-8441. Last year, we published a new global fit for normal methanol covering the first three torsional states (1 = 0, 1 and 2) for J values up to 30 !. The global fit of approximately 5600 frequency measurements and 19 000 Fourier transform far infrared (FTFIR) wavenumber measurements to 119 parameters reached the estimated experimental measurement accuracy for the FTFIR transitions, and about twice the estimated experimental measurement accuracy for the microwave, submillimeterwave and terahertz transitions. Due to a number of complications in that data set, we designated the work as a ”living document” and encouraged measurement laboratories represented in the data set to assess carefully how their data were treated, and to partition (if appropriate) their measurements into an optimum set (for which they specify their highest measurement precision) and a less good set (for which they specify a reduced measurement precision). Using the new JPL spectrometer and additional improved measurements, we have recently revisited a large number of transitions. Poor line shapes due either to power saturation or blending were carefully treated with a multi-line peakfinding procedure and assessed with more realistic uncertainties. Assignments were also extended to higher K and J. Several perturbed systems have been identified with complicated networks of interactions. The current data set now contains nearly 9500 frequency measured transitions. While we believe that this represents a substantial improvement on the quantum number coverage of our previous paper ! , we are also aware of continuing problems in our data fitting. Above all, we are facing challenges moving into a more complicated region with networks of interactions coupling different torsional states. ! Li-Hong Xu, J. Fisher, R.M. Lees, H.Y. Shi, J.T. Hougen, J.C. Pearson, B.J. Drouin, G.A. Blake, R. Braakman, 2008, J. Mol. Spectrosc., 251, 305-313. WH09 THE JPL MILLIMETER AND SUBMILLIMETER SPECTRAL LINE CATALOG 15 min 4:37 BRIAN J. DROUIN, JOHN C. PEARSON, Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109-8099. Recent concerns regarding interstellar line confusion has revived astrophysical support for the Jet Propulsion Laboratory’s Millimeter and Submillimeter Spectral Line Catalog. This catalog was originally designed as a tool for the planning and interpretation of atmospheric, planetary and astronomical observations at long wavelengths. The traditional format (ASCII files available via ftp or http) has been sufficient for atmospheric science missions and individual astronomers; however the complexity of astrophysical sources and the comprehensive spectra expected from future telescopes (e.g. Herschel and ALMA) require a more modern approach to the database and its tools. The current catalog interface is designed for (human) users who might browse and search the contents. Users with large data analysis problems have been required to develop their own assimilation tools. However, the large data analysis problem is likely to become the regular problem; therefore the development of astronomical data analysis tools that seamlessly utilize the comprehensive spectroscopic data will be a primary driver for the upgrades. Some of the planned upgrades include: the file infra-structure will be cast into a database structure compatible with modern client tools; the development of a systematic and user/machine-friendly citation tool. Synergistic upgrades for the atmospheric usage of the database will also be highlighted. We will also discuss new or planned changes to the catalog species. 200 WH10 THE ROTATIONAL SPECTRUM OF ACRYLONITRILE TO 1.67 THz 15 min 4:54 ZBIGNIEW KISIEL, LECH PSZCZÓŁKOWSKI, Institute of Physics, Polish Academy of Sciences, Al. Lotników 32/46, 02-668 Warszawa, Poland; BRIAN J. DROUIN, CAROLYN S. BRAUER, SHANSHAN YU, JOHN C. PEARSON, Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109-8099, USA. Acrylonitrile (vinyl cyanide) is an astrophysical molecule of sufficient abundance for detection of its C isotopologues. a In fact this molecule has been identified as one of the ’weed’ species, that will contribute a plethora of lines in broadband submillimetre spectra from the new tools of radioastronomy, such as the Herschel Space Observatory or ALMA. We presently report the first stage in extending the knowledge of the rotational spectrum of acrylonitrile well into the THz region. The spectrum was recorded with the jpl cascaded harmonic multiplication instrument b in the form of several broadband segments covering 390-540, 818-930, 967-1160, and 1576-1669 GHz. The analysis of the ground state spectrum has been extended up to & , ' , and a combined data set of over 3000 fitted lines. It is found that transitions in all measurable vibrational states, inclusive of the ground state, show evidence of perturbations with other states. Several different perturbations between the ground state and 1 at 228 cm were identified and have been successfully fitted, resulting in =228.29994(3) cm , to compare with a direct far-infrared value c of 228.83(18) cm . a H.S.P.Müller et al., J. Mol. Spectrosc., 251, 319-325 (2008). F.W.Maiwald, J.C.Pearson, Rev. Sci. Instrum., 76, 093113-1-10 (2005). c A.R.H.Cole, A.A.Green, J. Mol. Spectrosc., 48, 246-253 (1973). b B.J.Drouin, WH11 TERAHERTZ SPECTROSCOPY OF THE GROUND STATE OF METHYLAMINE (CH NH ) 15 min 5:11 SHANSHAN YU and BRIAN J. DROUIN, Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109. Measurements of the torsion-rotation spectrum of methylamine have been extended into the terahertz region. The accuracy of these measurements is estimated to be ranging from 50 kHz to 100 kHz.. About 1000 lines were assigned based on a SPCAT prediction. The Hamiltonian model follows the group-theoretical formalism developed by Ohashi and Hougen a. These assigned lines were fitted together with all prior available data (1800 lines) using the SPFIT program, and improved molecular parameters were obtained for CH NH by adding the new measurements. New frequency and intensity predictions have been made based on the obtained molecular parameters. This Hamiltonian model may facilitate future studies on protonated methanol (CH OH ). a N. Ohashi and J. T.Hougen J. Mol. Spectrosco. 121, 474 (1987). 201 WH12 15 min 5:28 TERAHERTZ SPECTROSCOPY AND GLOBAL ANALYSIS OF THE BENDING VIBRATIONS OF C D C H and SHANSHAN YU, BRIAN J. DROUIN, JOHN C. PEARSON AND HERBERT M. PICKETT, Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109; VALERIO LATTANZI AND ADAM WALTERS, Centre d’Etude Spatiale des Rayonnements, Universit de Toulouse [UPS], CNRS [UMR 5187], 9 avenue du Colonel Roche, BP 44346, F-31028 Toulouse Cedex 4, France. Symmetric molecules have no permanent dipole moment and are undetectable by rotational spectroscopy. Their interstellar observations have previously been limited to mid-infrared vibration-rotation spectroscopy. Although relatively weak, vibrational difference bands provide a means for detection of non polar molecules by terahertz techniques with microwave precision. Herschel, SOFIA, and ALMA have the potential to identify a number of difference bands of light symmetric species, e.g., C H , CH and C . This paper reports the results of the laboratory study on C H and C D . The symmetric isotopomers of acetylene have two bending modes, the trans bending ( $ ), and the cis bending ( $ ). For C H , the two bending modes occur at 612 and 729 cm , respectively. For C D , the two bending modes occur at 511 and 538 cm . The - difference bands are allowed and occur in the microwave, terahertz, and far-infrared wavelengths, with band origins at 117 cm (3500 GHz) for C H and 27 cm (900 GHz) for C D . Two hundred and fifty-one C D transitions, which are from - , ( + )-2 and 2 -( + ) bands, have been measured in the 0.2-1.6 THz region, and 202 of them were observed for the first time. The precision of these measurements is estimated to be from 50 kHz to 100 kHz. A multistate analysis was carried out for the bending vibrational modes and of C D , which includes the lines observed in this work and prior microwave, far-infrared and infrared data on the pure bending levels. Significantly improved molecular parameters were obtained for C D by adding the new measurements to the old data set which had only 10 lines with microwave measurement precision. The experiments on C H are in progress and ten " branch lines have been observed. We will present the C H results to date. WH13 15 min 5:45 SUBMILLIMETER SPECTROSCOPY OF THE OUT-OF-PLANE BENDING STATE OF C H CN JOHN C. PEARSON, CAROLYN S. BRAUER, SHANSHAN YU, and BRIAN J. DROUIN, JET PROPULSION LABORATORY, CALIFORNIA INSTITUTE OF TECHNOLOGY, 4800 OAK GROVE DR., PASADENA, CA 91109. Propionitrile is a well known interstellar molecule that is a closely associated with warm dust near ultra compact regions. In these regions the C H CN column can reach and the rotational temperature often equals the vibrational temperature and exceeds 200 K, populating all the low-lying vibrational states. The rotational spectrum of the third lowest excited vibrational state, the 378 cm out-of-plane bending state, , of propionitrile, which was previously identified at millimeter wavelengths in both the laboratory and the interstellar medium, has been characterized to high angular momentum quantum numbers. This state is surprisingly isolated considering its proximity to the overtone of the in-plane bend, 2 , the excited torsional state of the in-plane bend, , and the second excited torsional state, , which lie approximately 35 cm higher. The only surprising aspect is the presence of significantly larger torsional A-E splitting than observed in either the ground state or the in the absence of a resonance with . Because has been observed in high mass star forming cores in the millimeter, its higher angular momentum lines are known to be a major source of line confusion in high mass star forming cores. The spectrum, constants and determined barriers will be presented. 202 WI. ASTRONOMICAL SPECIES AND PROCESSES WEDNESDAY, JUNE 24, 2009 – 1:30 PM Room: 1015 MCPHERSON LAB Chair: SUSANNA WIDICUS WEAVER, Emory University, Atlanta, Georgia WI01 COSMOLOGICAL NUCLEOSYNTHESIS: THE LITHIUM PROBLEM 10 min 1:30 DOUGLAS N. FRIEDEL, ATHOL KEMBALL, and BRIAN FIELDS, Department of Astronomy, University of Illinois, 1002 W. Green St., Urbana, IL 61801. A measurement of the primordial Lithium abundance would give a significant observational constraint to current big-bang nucleosynthesis models. Deuterium and helium abundances agree closely with predictions of current cosmological models, however, the predicted primordial lithium abundance is a factor of two above current measurements of the stellar lithium abundance obtained from optical spectroscopy of halo star atmospheres. Current optical measurements of stellar lithium abundances are subject to significant systematic uncertainties. Millimeter wavelength observations of the =0, & LiH rotational line, red-shifted from its rest frequency near 444 GHz, where it is significantly absorbed in the atmosphere, offer the opportunity to measure interstellar LiH abundance and isotopic ratios in extra-galactic sources. However, these observations have been difficult with older millimeter-wavelength telescopes and arrays, and a search and tentative (2-3 sigma) detection has been reported only towards one source: the lens B0218+357 (Combes & Wiklind 1998, AALett, 334, L81). We will present the results of our search for LiH and LiH toward several extragalactic sources. WI02 15 min 1:42 DISCOVERY OF MASSIVE YOUNG STELLAR OBJECTS IN THE GALACTIC CENTER WITH WARM CO GAS ABSORPTION DEOKKEUN AN, SOLANGE RAMIREZ, IPAC/CALTECH; KRIS SELLGREN, OHIO STATE U.; ADWIN BOOGERT, CALTECH; RICHARD ARENDT, NASA/GODDARD SPACE FLIGHT CENTER; ANGELA COTERA, SETI INSTITUTE; THOMAS ROBITAILLE, ST. ANDREWS U., UK; MATHIAS SCHULTHEIS, OBS. BESANCON, FRANCE; HOWARD A. SMITH, HARVARD-SMITHSONIAN CENTER FOR ASTROPHYSICS; SUSAN STOLOVY, SPITZER SCIENCE CENTER, CALTECH. We report the detection of several molecular gas-phase and ice absorption features in three photometrically-selected young stellar object (YSOs) candidates in the central 280 pc of the Milky Way. Our spectra, obtained with the Infrared Spectrograph (IRS) onboard the Spitzer Space Telescope, reveal gas-phase absorption from CO (15.0 m), C H (13.7 m) and HCN (14.0 m). We attribute this absorption to warm, dense gas in the massive YSOs. We also detect strong and broad 15.2 m CO ice absorption features, with an absorption profile indicating the presence of thermally processed CO ice. Our IRS observations demonstrate the youth of these objects, and provide the first spectroscopic identification of massive YSOs in the Galactic Center. 203 WI03 15 min 1:59 MILLIMETER DETECTION OF AlO MAJORIS (X ): METAL OXIDE CHEMISTRY IN THE ENVELOPE OF VY CANIS E. D. TENENBAUM, L. M. ZIURYS, University of Arizona, Steward Observatory, Department of Chemistry, Arizona Radio Observatory Tucson, AZ 85721. A new circumstellar molecule, the radical AlO (X ), has been detected toward the envelope of the oxygen-rich supergiant star VY Canis Majoris (VY CMa) using the Arizona Radio Observatory (ARO). The N = 7 6 and 6 5 rotational transitions of AlO at 268 and 230 GHz were observed at 1 mm using the ARO Submillimeter Telescope (SMT) and the N = 4 3 line was detected at 2 mm using the ARO 12 m. Based on the shape of the line profiles, AlO most likely arises from the dust-forming region in the spherical outflow of VY CMa, as opposed to the blue- or red-shifted winds, with a source size of C 0.5 . Given this source size, the column density of AlO was found to be N cm for T 230 K, with a fractional abundance, relative to H , of 10 . Gas-phase thermodynamic equilibrium chemistry is the likely formation mechanism for AlO in VY CMa, but shocks may disrupt the condensation process into Al O , allowing AlO to survive to a radius of 20 R . The detection of AlO in VY CMa is additional evidence of an active gas-phase refractory chemistry in oxygen-rich envelopes, and suggests such objects may be fruitful sources for other new oxide identifications. WI04 15 min 2:16 GROUND-BASED OBSERVATIONS OF INTERSTELLAR CN AND THE C/ C RATIO AND THE EXCITATION OF CN CH IN DIFFUSE MOLECULAR CLOUDS: ADAM M. RITCHEY, STEVEN R. FEDERMAN, YARON SHEFFER, Department of Physics and Astronomy, University of Toledo, Toledo, OH 43606; and DAVID L. LAMBERT, W. J. McDonald Observatory, University of Texas, Austin, TX 78712. We present high signal-to-noise ratio observations of optical transitions in CN and CH for a number of Galactic diffuse clouds. The data are examined to extract the CN/ CN and CH / CH ratios along each line of sight in order to assess predictions of diffuse cloud chemistry. We find a weighted mean CH / CH ratio of 74.4 7.6. This result is consistent with the average C/ C ratio of 70 7 for local interstellar clouds, confirming the theoretical expectation that CH / CH represents the ambient carbon isotopic ratio. Our sample includes three sight lines for which previous studies had found much lower values of CH / CH that are not confirmed here. Thus, we find no evidence for variation in C/ C within 1 kpc of the Sun. The 12-to-13 ratios in both CN and CO, however, show significant fractionation away from the ambient value due to the opposing effects of photodissociation and charge exchange reactions. Our CN/ CN measurements are combined with determinations of CO/ CO from the literature to enable a detailed analysis of the effects of chemical fractionation in diffuse molecular clouds. We find suggestive evidence for an inverse relationship between CN/ CN and CO/ CO, resulting from the physical association of CN and CO in the cores of the clouds. Additionally, the isotopologic ratios examined here suggest that about 20 percent of C is locked up in CO in typical diffuse cloud cores, while up to 85 percent may reside in CO in the central portions of the Ophiuchus diffuse clouds. Finally, we examine rotational excitation temperatures in both CN and CN. Our weighted mean value of : ( CN) = 2.754 0.002 K implies an excess over the cosmic microwave background (CMB) of only 29 3 mK, considerably smaller than some recent surveys have suggested. This modest excess can be accounted for if collisional excitation by electrons is occurring locally in some clouds, with derived electron densities of = 0.1 0.5 cm . Yet, given the dispersion of 134 mK in our individual : measurements, the excess may not be physical. There is some indication of a greater excess in : ( CN) based on our weighted mean of 2.847 0.014 K, but the dispersion in these measurements is also greater (259 mK). The rotational excitation temperature observed in CN, via the (0), (1), and " (1) lines, shows no excess over the CMB. 204 WI05 A SEARCH FOR INTERSTELLAR UREA WITH CARMA 15 min 2:33 H.-L. KUO, L. E. SNYDER, D. N. FRIEDEL, L. W. LOONEY, Department of Astronomy, University of Illinois at Urbana-Champaign; B. J. McCALL, Departments of Chemistry and Astronomy, University of Illinois at Urbana-Champaign, Urbana IL 61801; A. J. REMIJAN, NRAO, Charlottesville VA 22903; F.J. LOVAS, Optical Technology Division, NIST, Gaithersburg MD 20899-8441; J. M. HOLLIS, NASA/GSFC, Code 606, Greenbelt MD 20771. Urea, a molecule discovered in human urine by H. M Rouelle in 1773, also plays a significant role in prebiotic chemistry. Previous BIMA observations have suggested that interstellar urea [(NH ) CO] is a compact hot core molecule such as the other large molecules methyl formate and acetic acid (2008, 63rd OSU Symposium On Molecular Spectroscopy, RF11). We have conducted an extensive search for urea toward the high mass hot molecular core Sgr B2(N-LMH) using the CARMA array. The resolution at 1 mm enables favorable coupling of source size and synthesized beam size, which was found to be essential for flux measurements and detection limits of weak signals. The 2.5 2 synthesized beam of CARMA significantly resolves out the extended emission and reveals the weak lines that were previously blended with nearby transitions. Our analysis indicates that these lines are likely to be urea since they are now less contaminated, the resulting observed line frequencies are coincident with a set of overlapping connecting urea lines, and the observed line intensities are consistent with expected line strengths of urea. WI06 15 min 2:50 BROADBAND AND CAVITY SPECTROSCOPY OF THIOFULMINIC ACID HCNS AND THIOISOFULMINIC ACID HSNC, AND A SYSTEMATIC ASTRONOMICAL SEARCH FOR THE FOUR [H,C,N,S] ISOMERS IN SGR B2 WITH THE GREEN BANK TELESCOPE M. C. MCCARTHY, C. A. GOTTLIEB, P. THADDEUS, Harvard-Smithsonian Center for Astrophysics, 60 Garden St., Cambridge, MA 02138, and School of Engineering & Applied Sciences, Harvard University, 29 Oxford St., Cambridge, MA 02138; M.T. MUCKLE, J.L. NEILL, B. H. PATE, Department of Chemistry, University of Virginia, McCormick Rd., Charlottesville, VA 22904-4319; SVEN THORWIRTH, MaxPlanck-Institut für Radioastronomie, Auf dem H ügel 69, 53121 Bonn, Germany; S. BR ÜNKEN, Laboratoire de Chimie Physique Moléculaire, École Polytechnique Fédérale de Lausanne, Station 6, CH-1015 Lausanne, Switzerland; ARNAUD BELLOCHE, LIES VERHEYEN, KARL M. MENTEN, Max-Planck-Institut f ür Radioastronomie, Auf dem H ügel 69, 53121 Bonn, Germany; and ANTHONY J. REMIJAN, National Radio Astronomy Observatory, 520 Edgemont Road, Charlottesville, VA 22903. The rotational spectra of thiofulminic acid, HCNS, and isothiofulminic acid, HSNC, two energetic [H,C,N,S] isomers calculated to lie about 35 kcal/mol above HNCS, have been observed at high spectral resolution by a combination of broadband and Fabry-Pérot FT microwave spectroscopy between 11 and 37 GHz. Searches for both isomers were based on high level coupled cluster calculations. Precise rotational, centrifugal distortion, and nitrogen hyperfine coupling constants have been determined for the normal and rare isotopic species of both closed-shell molecules; all in good agreement with theoretical predictions. On the basis of this work and prior rotational spectroscopy on HNCS and HSCN, a systematic search for the four [H,C,N,S] isomers has been undertaken towards Sgr B2 using the 100 m Green Bank Telescope. In Sgr B2(M), we find no evidence for either HCNS or HSNC, and surprisingly no evidence for the ground state HNCS, but there is very suggestive evidence for HSCN, the second most stable isomer calculated to lie approximately 6 kcal/mol higher in energy. A summary of our observations towards Sgr B2(M) and other regions of Sgr B2 will be presented. 205 WI07 GAS-GRAIN MODELING OF HNCO, HOCN, HCNO, AND HONC 15 min 3:07 DONGHUI QUAN, Chemical Physics Program, The Ohio State University, Columbus, OH 43210; ERIC HERBST, Departments of Physics, Astronomy, & Chemistry, The Ohio State University, Columbus, OH 43210. Among isomers made of H, C, N, and O, the lowest energy isomer, isocyanic acid (HNCO), has been detected towards various interstellar sources, ranging from cold dense cores such as TMC-1 to hot cores such as SgrB2(M). One metastable isomer, fulminic acid (HCNO), has been detected in cold cores, as well as the lukewarm core L1527 (Marcelino et al., 2009, ApJ 690, L27). Here we present gas-grain model studies of HNCO and HCNO, as well as two other isomers, cyanic acid (HOCN) and isofulminic acid (HONC). We apply four models: a warm-up hot core model where : starts at 10 K and increases to 200 K over a time of 2 10 yr and then remains at 200 K; a warm-up hot-core envelope model where : increases from 10 K to 50 K over the same time period; a warm-up lukewarm model where : increases from 10 K to 30 K; and a model where : remains constant at 10 K. In the hot core warm-up model, the increase in temperature produces an increase in gas-phase abundance for all four isomers. In the envelope warm-up model, the HNCO and HOCN abundances increase, the HCNO abundance is unchanged, while HONC slightly decreases as : increases. In the lukewarm model, within the time range investigated, both calculated HNCO and HCNO fractional abundance in the gas phase are in good agreement with observed abundances except at the very beginning. HOCN shows a low calculated abundance before 1 10 yr, after which it starts increasing and reaches relatively detectable value of 7 10 and remains abundant afterwards. In the constant low temperature model, the observed fractional abundance of HNCO towards TMC-1 is reproduced at a time of 1 10 yr, at which time the other two isomers have abundances about two orders of magnitude lower than HNCO, a result in reasonable agreement with the gas-phase steady-state model of Marcelino et al. Intermission WI08 THERMALIZATION OF INTERSTELLAR CO 10 min 3:40 TAKESHI OKA, Department of Astronomy and Astrophysics and Department of Chemistry, The Enrico Fermi Institute, University of Chicago, Chicago, IL 60637; HAN XIAO, and PHILLIP LYNCH, Department of Statistics, University of Chicago, Chicago, IL 60637. Unlike radio emission of CO, infrared absorption of CO give column densities in each rotational level directly when weak transitions like overtone bands or CO or C O isotope bands are used. This allows more straightforward determination of temperature (: ) and density ( ) of the environment than the large velocity gradient (LVG) model used to determine them from antenna temperatures of radio emission. In order to facilitate such determination, we have solved the steady state linear simultaneous equations for thermalization of CO and calculated population ratios of rotational levels as a function a of : and as we did for H . We thus get two-dimensional graph of column density ratios, for example, (& =1)/ (& =0) and (& =2)/ (& =0) as a function of : and or variation of it when other population ratios are used. As for H we can invert the graph to obtain graphs of : versus as functions of population ratios which is more convenient to apply to observed data. b We use rate constants of collision-induced transitions between CO and ortho- and para-H theoretically calculated by Fowlerc and Wernli et al.d which have been compiled and extended by Schöier et al. e As the first approximation, only spontaneous emissions are considered and other radiative effects such as induced emission and absorption are ignored. The results are applied to CO column densities observed toward the Galactic center, that is, CO in the three spiral arms, 3-kpc (Norma), 4.5-kpc (Scutum), and local arms (Sagittarius), and in the Central Molecular Zone. a T. Oka and E. Epp, ApJ, 613, 349 (2004) Goto, Usuda, Nagata, Geballe, McCall, Indriolo, Suto, Henning, Morong, and Oka, ApJ, 688, 306 (2008) c D. R. Fowler, J. Phys. B: At. Mol. Opt. Phys. 34, 2731 (2001) d M. Wernli, P. Valiron, A. Faure, L. Wiesenfeld, P. Jankowski, and K. Szalewicz, A & A, 446, 367 (2006) e F. L. Schöier, F. F. S. van der Tak, E. F. van Dishoeck, and J. H. Black, A & A, 432, 369 (2005) b M. 206 WI09 15 min 3:52 VARIABILITY OF THE COSMIC-RAY IONIZATION RATE IN DIFFUSE MOLECULAR CLOUDS NICK INDRIOLO, Department of Astronomy, University of Illinois at Urbana-Champaign, Urbana, IL 61801; THOMAS R. GEBALLE, Gemini Observatory, Hilo, HI 96720; TAKESHI OKA, Department of Astronomy & Astrophysics and Department of Chemistry, University of Chicago, Chicago, IL 60637; BENJAMIN J. McCALL, Departments of Astronomy and Chemistry, University of Illinois at Urbana-Champaign, Urbana, IL 61801. The energy spectrum of cosmic-rays — a product of particle acceleration and subsequent diffusion — is generally assumed to be uniform throughout the Galaxy a . As a result, the cosmic-ray ionization rate inferred in similar environments (e.g. in several diffuse clouds) should also be relatively constant. However, current estimates of the ionization rate in diffuse molecular clouds vary over the range s . In addition, there are a few sight lines with ! upper limits of D 5 s , suggesting even lower ionization rates in some clouds. This roughly order of magnitude difference in the cosmic-ray ionization rate between sight lines contradicts the concept of a spatially uniform cosmic-ray flux. We present cosmic-ray ionization rates derived from several published bc and unpublished spectroscopic observations of H in diffuse cloud sight lines. These ionization rates are then compared with various other parameters (Galactic latitude, Galactic longitude, hydrogen column density) in a search for correlations. Also, sight lines in close proximity are compared to each other to determine the variability of the ionization rate on small spatial scales. a Webber, W. R. 1998, ApJ, 506, 329 N., Geballe, T. R., Oka, T., & McCall, B. J. 2007, ApJ, 671, 1736 c McCall B. J., et al. 2002, ApJ, 567, 391 b Indriolo, WI10 CAN WE USE METASTABLE HELIUM TO TRACE THE COSMIC-RAY IONIZATION RATE? 15 min 4:09 NICK INDRIOLOa , Department of Astronomy, University of Illinois at Urbana-Champaign, Urbana, IL 61801; LEWIS M. HOBBS, University of Chicago, Yerkes Observatory, Williams Bay, WI 53191; KENNETH H. HINKLE, National Optical Astronomy Observatories, Tucson, AZ 85726; BENJAMIN J. McCALL, Departments of Astronomy and Chemistry, University of Illinois at Urbana-Champaign, Urbana, IL 61801. The ionization rate of interstellar material by cosmic rays has been a major source of controversy, with different estimates varying by three orders of magnitude. Direct observational measurements of this rate have all depended on analyzing the chemistry of various molecules such as OH, HD, HCO , H O , and H , which are produced following cosmic-ray ionization. In many cases the chemical analyses contain important uncertainties; even in the simplest case, that of H , the derived ionization rate depends on an (uncertain) estimate of the absorption path length. The reaction network producing metastable helium, on the other hand, is believed to be extremely simple, thus providing a direct measure of the cosmic-ray ionization rate. We present spectroscopic observations made searching for the 10830 Å absorption line of He I* due to interstellar material in the first attempt to utilize this probe. We will then discuss complications to the metastable helium chemistry, and examine the instrumental capabilities needed to utilize this new probe of the ionization rate. a nindrio2@illinois.edu 207 WI11 15 min 4:26 SPECTROSCOPIC STUDIES OF THE TURES H + H REACTION AT ASTROPHYSICALLY RELEVANT TEMPERA- BRIAN A. TOM, BRETT A. McGUIRE, LAUREN E. MOORE, THOMAS J. WOOD, Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, IL 61801; BENJAMIN J. McCALL, Departments of Chemistry and Astronomy, University of Illinois at Urbana-Champaign, Urbana, IL 61801. H is the key precursor to ion chemistry in the interstellar medium. It has been employed as an astrophysical probe of conditions of temperature and density due to its ubiquity in a variety of environments. The distribution of ortho- and paraspin modifications of H is particularly interesting in this regard. Consequently, it is important to understand the pathways through which changes to the H spin distribution can occur. One possible pathway is the H + H H + H reaction, which proceeds by proton hop and proton exchange and is governed by the conservation of nuclear spin. Cordonnier et al. a studies this reaction at high temperature in a pulsed hollow cathode cell, but to facilitate the understanding of astronomical observations, we need lower temperature measurements. Recently, we have constructed a liquid nitrogen-cooled hollow cathode discharge source and coupled it with multipass absorption spectroscopy to measure the ortho:para ratio of H in plasmas at a variety of para-H enrichment levels at 160 K. Previously, we have reported b experimental measurements of the branching ratio between proton hop and exchange in a hydrogenic plasma at 80 K. Together, these experiments have allowed us to explore the temperature dependence of this branching ratio and provide valuable information for the interpretation of astronomical observations. a M. Cordonnier et al., J Chem Phys, 113, 3181 (2000) A. Tom, M. B. Wiczer, A. A. Mills, K. N. Crabtree, and B. J. McCall, “Observation of nuclear spin selection rules in supersonically expanding rd International Symposium on Molecular Spectroscopy (2008). plasmas containing H ,” 63 b B. WI12 15 min 4:43 PRODUCT BRANCHING RATIOS OF THE REACTION OF CO WITH H AND ITS ISOTOPOMERS HUA-GEN YU, Department of Chemistry, Brookhaven National Laboratory, Upton, NY 11973. The reaction of CO with H , H D and HD has been studied using a direct ab initio molecular dynamics method, where the energies and forces used in trajectory propagations are determined by a SAC (scaling all correlation)-MP2/cc pVTZ theory. For the H + CO reaction, there are two product channels: (H + HCO ) and (H + HOC ). At room temperature, the thermal rate coefficient is predicted to be 1.37 cm .molecule .s with a product branching ratio [HOC ]/[HCO ]=0.28. In addition, dynamics results for the CO + H D /HD reactions will also be reported. WI13 A NEW INTERSTELLAR MODEL FOR HIGH-TEMPERATURE TIME-DEPENDENT KINETICS 15 min 5:00 NANASE HARADA, Department of Physics, The Ohio State University, Columbus OH 43210; ERIC HERBST, Departments of Physics, Astronomy, and Chemistry, The Ohio State University, Columbus, OH 43210. We have developed a kinetic approach to investigate time-dependent, high-temperature interstellar chemistry that can occur up to 1000 K. The network used is an expanded OSU gas-phase network, which includes both exothermic processes with barriers and endothermic reactions. The rates of reactions between ions and polar neutral species were modified to have less temperature dependence at high temperature. Our calculations show that H O and NH are more abundant forms of oxygen and nitrogen than atomic oxygen, atomic nitrogen, and N , which are dominant in cold clouds. Methane became more abundant in the high-temperature model than in the cold cloud model while CO is still the dominant form of carbon. Higher abundances of H O and CH are also obtained by a thermodynamic model (Markwick et al) although it does not produce the variety of molecules that have been observed in high-temperature sources. When an appropriate cosmic-ray induced ionization or X-ray ionization is incorporated, this expanded network can be applied to dynamic models such as those needed for active galactic nuclei, which will be observed in some detail when ALMA becomes fully operational. 208 WI14 THE OPTICAL SPECTRUM OF THIOZONE S AND OTHER SULFUR RICH SYSTEMS 15 min 5:17 DAMIAN L. KOKKIN, MICHAEL C. McCARTHY, and PATRICK THADDEUS, Harvard-Smithsonian Center for Astrophysics, 60 Garden St., Cambridge, MA 02138, and School of Engineering & Applied Sciences, Harvard University, 29 Oxford St., Cambridge, MA 02138. The recent discovery and mapping of S and SO in the plume of Pele, one of the largest and most active volcanoes on Io, the innermost moon of Jupiter, suggests that other sulfur rich molecules may be abundant in this unusual planetary source.a b Optical images of Io in the range 3900 Å - 5000 Å conclude as much: the observed flux intensity cannot be attributed to transitions of these molecules alone. c By means of 2-colour resonant-2-photon ionisation time of flight mass spectroscopy the optical spectrum of thiozone S and other sulfur rich systems have now been detected. For thiozone a progression in the excited state bending mode is seen with a frequency of 350 cm built onto the origin band at 433.82 nm. In this talk our results are compared to prior experimental matrix and low-resolution gas-phase work. The prospects for finding these atomic clusters in the atmosphere of Io will be discussed. a J. R. Spencer, K. L. Jessup, M. A. McGrath, G. E. Ballester and R. Yelle, Science, 288, 1208-1210, 2008 Mollet, E. Lellouch, R. Moreno, M. A. Gurwell and C. Moore, A&A, 482, 279-292, 2008 c P. Geissler, A. McEwen, C. Porco, D. Strobel, J. Saur, J. Ajello and R. West, Icarus, 172, 127-140, 2004 b A. WI15 10 min 5:34 LABORATORY MEASUREMENT OF THE CO CAMERON BANDS AND VISIBLE EMISSIONS FOLLOWING VUV PHOTODISSOCIATION OF CO K. S. KALOGERAKIS, C. ROMANESCU, T. G. SLANGER, SRI International, Mol. Phys. Lab., Menlo Park, CA 94025; L. C. LEE, San Diego State Univ., Dept. Elect. & Comp. Eng., San Diego, CA 92182; M. AHMED and K. R. WILSON , Univ. Calif. Berkeley, Lawrence Berkeley Lab., Div. Chem. Sci., Berkeley, CA 94720. The CO(a X ) Cameron bands are one of the most important emission features in the UV dayglow of the CO planets, as demonstrated in the case of Mars by the measurements performed by Mariner and Mars Express missions. One of the mechanisms to produce electronically excited CO(a ) is photodissociation of CO at wavelengths shorter than 108 nm. At wavelengths below 100 nm, new CO photodissociation channels open leading to formation of higher energy triplet states of CO. These states cascade into the lower triplet state by emission in the visible spectral region before radiating in the Cameron system. This two step relaxation pathway was demonstrated by Lee and Judge a for the 90-93 nm photodissociation of CO . We have further investigated this process using the 85-110 nm tunable synchrotron radiation at the Advanced Light Source facility at Lawrence Berkeley Laboratory. The experimental results confirmed that once a triplet state excitation threshold is exceeded, a fraction of the Cameron band emission is accompanied by visible emission. These results indicate that the emission corresponding to the CO(a -a, d-a, e-a) triplet bands must be part of the visible Mars / Venus dayglow. The same is true for CO photoexcitation in cometary atmospheres. This work was supported by the NASA Outer Planets Research Program under grant NNX06AB82G. The Advanced Light Source is supported by the Director, Office of Science, Office of Basic Energy Sciences, of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. a D. L. Judge and L. C. Lee, J. Chem. Phys., 58, 104 (1973) 209 WI16 Post-deadline Abstract – Original Abstract Withdrawn 15 min 5:46 AN EXHAUSTIVE ISOTOPIC STUDY OF THE ABUNDANT ASTRONOMICAL MOLECULE CYCLOPROPENYLIDENE, c-C H SILVIA SPEZZANO, C. A. GOTTLIEB, M. C. McCARTHY AND P. THADDEUS, Harvard-Smithsonian Center for Astrophysics, 60 Garden St., Cambridge, MA 02138, and School of Engineering & Applied Sciences, Harvard University, 29 Oxford St., Cambridge, MA 02138. Cyclopropenylidene, c-C H , is the most widely distributed ring in our galaxy; it has been detected in more than 50 astronomical sources, and its isotopic species c-C HD has been observed towards several dense cores in cold dark clouds. Because of the high observed abundance and large deuterium fractionation for this small hydrocarbon ring, other isotopic species of c-C H may be good candidates for astronomical detection. For these reasons, an exhaustive isotopic study of c-C H has now been undertaken in which rotational spectra of c-C D , c-C HD, and the carbon–13 isotopic species of c-C HD and c-C H have been detected in the centimeter-wave band by Fourier transform microwave (FTM) spectroscopy between 10 and 40 GHz. For c-C D , millimeter- and submillimeter-wave spectra were subsequently measured between 140 and 400 GHz. Rotational and centrifugal distortion constants derived either from previous measurements or those predicted from theory are compared with the precise constants determined here. 210 WJ. MINI-SYMPOSIUM: CONICAL INTERSECTIONS WEDNESDAY, JUNE 24, 2009 – 1:30 PM Room: 2015 McPHERSON LAB Chair: SPIRIDOULA MATSIKA, Temple University, Philadelphia, Pennsylvania WJ01 INVITED TALK WATCHING ELECTRONS AT CONICAL INTERSECTIONS AND FUNNELS 30 min 1:30 DAVID M. JONAS, ERIC R. SMITH, WILLIAM K. PETERS, KATHERINE A. KITNEY, Department of Chemistry and Biochemistry, University of Colorado, Boulder, CO 80309-0215. The electronic motion at conical intersections and funnels is probed after polarized excitation of aligned electronic wavepackets. The pulses have bandwidth sufficient to observe vibrations mainly through their effect on the electrons. Vibrational symmetry can be identified by the polarization anisotropy of vibrational quantum beats. The polarized transients show signatures of electronic wavepacket motion (due to the energy gaps) and of electron transfer between orbitals (due to the couplings) driven by the conical intersection. For a conical intersection in a four-fold symmetric symmetry silicon naphthalocyanine molecule, electronic motions on a 100 fs timescale are driven by couplings of 1 meV. In the lower symmetry free-base naphthalocyanine, the conical intersection may be missed or missing (conical funnel), and the motions are nearly as rapid, but electronic equilibration is incomplete for red-edge excitation. These experiments probe non-adiabatic electronic dynamics with near-zero nuclear momentum - the electronic motions are determined by the principal slopes of the conical intersection and the width of the vibrational wavepacket. WJ02 15 min 2:05 THE CONICAL INTERSECTIONS BETWEEN L and L STATES IN TRYPTAMINE AND INDOLE Ch. BRAND, Institut für Physikalische Chemie I, Heinrich-Heine-Universit ät, Universitätsstraße 26.43.02.43 D-40225 D üsseldorf, Germany; J. KÜPPER, Fritz-Haber-Institut der Max-Planck-Gesellschaft, 14195 Berlin, Germany; W. LEO MEERTS, Molecular and Biophysics Group, Institute for Molecules and Materials,Radboud University, 6500 GL Nijmegen, The Netherlands; D. W. PRATT, University of Pittsburgh, Department of Chemistry, Pittsburgh, PA 15260, USA; J ÖRG TATCHEN, Chemical Physics Department, Weizmann Institute of Science, 76100 Rehovot, Israel; and M. SCHMITT, Institut f ür Physikalische Chemie I, HeinrichHeine-Universität, Universitätsstraße 26.43.02.43 D-40225 D üsseldorf, Germany. The absorption spectrum of the lowest two excited singlet states of indole and tryptamine are calculated using FranckCondon-Herzberg-Teller (FCHT) theory. The derivatives of the transition dipole moments with respect to the normal coordinates are computed numerically at the combined density functional theory multi-reference configuration interaction (DFT/MRCI) level of theory. All valence electrons were correlated in the MRCI runs and the eigenvalues and eigenvectors of the lowest singlet state were determined. The initial set of reference configuration state functions was generated automatically in a complete active space type procedure (including all single and double excitations from the five highest occupied molecular orbitals in the KS determinant to the five lowest virtual orbitals) and was then iteratively improved. The HT integrals are obtained from Doktorovs recursive relations used for the calculation of the FC integrals. A conical intersection (CI) between L and L states in indole is calculated using DFT/MRCI to be located 2000 cm above the L origin, thus perturbing only slightly the vibronic spectrum of indole. For tryptamine the CI is calculated to be less than 1000 cm above the L origin and strong perturbation of the vibronic spectrum is expected and observed. 211 WJ03 15 min 2:22 HIGH RESOLUTION SPECTROSCOPY OF INDOLE DERIVATIVES NEAR CONICAL INTERSECTIONS: TRYPTAMINE AND INDOLE Ch. BRAND, Institut für Physikalische Chemie I, Heinrich-Heine-Universit ät, Universitätsstraße 26.43.02.43 D-40225 D üsseldorf, Germany; J. KÜPPER, Fritz-Haber-Institut der Max-Planck-Gesellschaft, 14195 Berlin, Germany; I. KALKMAN, W. LEO MEERTS, Molecular and Biophysics Group, Institute for Molecules and Materials,Radboud University, 6500 GL Nijmegen, The Netherlands; D. W. PRATT, University of Pittsburgh, Department of Chemistry, Pittsburgh, PA 15260, USA; and M. SCHMITT, Institut f ür Physikalische Chemie I, Heinrich-Heine-Universit ät, Universitätsstraße 26.43.02.43 D-40225 D üsseldorf, Germany. The rotationally resolved spectra of vibronic bands of indole and tryptamine in the region between the electronic origin and 1000 cm have been analyzed using an evolutionary strategy (ES) approach. The lowest two excited singlet states of the title compounds, which are labeled by L and L following the nomenclature by Platt are characterized regarding their excitation energies, geometric structures and their orientation of transition dipole moments (TDM). While the favorable orientation of the transition dipole moment nearly along the main inertial axes in tryptamine makes the assignments of vibronic bands to certain electronic states straightforward, indole poses a much more difficult problem. Here the TDM is oriented to lie between the and * inertial axes, what causes an uncertainty of the sign of the TDM. This problem can be overcome by fitting the intensities in the vibronic spectrum to a model Hamiltonian, which includes axis reorientation using the ES approach. From the relative sign of the TDM angle with the axis reorientation angle a distinction between both electronic states can be made. A conical intersection (CI) between L and L states in indole is calculated using DFT/MRCI to be located 2000 cm above the L origin, thus perturbing only slightly the vibronic spectrum of indole. For tryptamine the CI is calculated to be less than 1000 cm above the L origin and strong perturbation of the vibronic spectrum is expected and observed. The vibronic coupling between L and L states is calculated using Franck-Condon-Herzberg-Teller theory. The derivatives of the transition dipole moments with respect to the normal coordinates are computed numerical at the DFT/MRCI level of theory. Computed spectra for indole and tryptamine show very good agreement with the experimental ones. WJ04 15 min 2:39 MULTI-STATE VIBRONIC INTERACTIONS IN FLUORINATED BENZENE RADICAL CATIONS. S. FARAJI, H. KÖPPEL, Theoretische Chemie, Physikalisch-Chemisches Institut, Universit ät Heidelberg, Im Neuenheimer Feld 229, D-69120 Heidelberg, Germany. Conical intersections of potential energy surfaces have emerged as paradigms for signalling strong nonadiabatic coupling effects a . An important class of systems where some of these effects have been analyzed in the literature, are the benzene and benzenoid cations, where the electronic structure, spectroscopy, and dynamics have received great attention in the literature. In the present work a brief overview is given over our theoretical treatments of multi-mode and multi-state vibronic interactions in the benzene radical cation and some of its fluorinated derivatives. The fluorobenzene derivatives are of systematic interest for at least two different reasons. (1) The reduction of symmetry by incomplete fluorination leads to a disappearance of the Jahn-Teller effect present in the parent cation. (2) A specific, more chemical effect of fluorination consists in the energetic increase of the lowest ! -type electronic states of the radical cations. The multi-mode multi-state vibronic interactions between the five lowest electronic states of the fluorobenzene radical cations are investigated theoretically, based on ab initio electronic structure data, and employing the well-established linear vibronic coupling model, augmented by quadratic coupling terms for the totally symmetric vibrational modes. Low-energy – and – – cationic states, conical intersections, and strong vibronic couplings are found to prevail within the set of while the interactions between these two sets of states are found to be weaker and depend on the particular isomer. This is attributed to the different location of the minima of the various conical intersections occurring in these systems. Wave-packet dynamical simulations for these coupled potential energy surfaces, utilizing the powerful multi-configuration time-dependent Hartree method b are performed. Ultrafast internal conversion processes and the analysis of the MATI and photo-electron spectra shed new light on the spectroscopy and fluorescence dynamics of these species c . a W. Domcke, D. R. Yarkony, and H. Köppel, Advanced Series in Physical Chemistry, World Scientific, Singapore (2004). H. Beck and A. Jäckle and G. A. Worth and H. -D. Meyer, Phys. Rep. 324, 1 (2000). c S. Faraji, H. Köppel, (Part I) ; S. Faraji, H. Köppel, H.-D. Meyer, (Part II) J. Chem. Phys. 129, 074310 (2008). b M. 212 WJ05 MULTIPHOTON IONIZATION AND DISSOCIATION OF DIAZIRINE 15 min 2:56 ANDREW K. MOLLNER, I. FEDOROV, L. KOZIOL, A. I. KRYLOV, H. REISLER, Department of Chemistry, University of Southern California, Los Angeles, CA 90089. Multiphoton ionization and dissociation processes in diazirine have been studied experimentally via 304-325 nm twophoton absorption, and theoretically by using the EOM-CCSD and B3LYP methods. The electronic structure calculations indicate the strongest one-photon absorption is to the (3 n) Rydberg state. However, in two-photon absorption at comparable energies the first photon excites the low-lying n) valence state, from which the strongest absorption is to the dissociative valence ! ) state. In the experimental studies, resonance enhanced multiphoton ionization (REMPI) experiments show no ions at the parent diazirine mass but only CH ions from dissociative photoionization. It is proposed that weak one-photon absorption to the state is immediately followed by more efficient absorption of another photon to reach the state from which competition between ionization and fast dissociation takes place. Strong signals of CH ions are also detected and assigned to 2+1 of CH fragments. Velocity map CH images show that CH fragments are born with substantial translational energy indicating that they arise from absorption of two photons in diazirine. It is argued that two-photon processes via the intermediate state are very efficient in this wavelength range, leading predominantly to dissociation of diazirine from the state. The most likely route to CH(X) formation is isomerization to isodiazirine followed by dissociation to CH + HN . WJ06 15 min 3:13 STRUCTURE OF THE PHOTOCHEMICAL REACTION PATHWAYS POPULATED VIA THE PROMOTION of CF I and CH I INTO THEIR FIRST ELECTRONICALLY EXCITED STATES P. Z. EL-KHOURY, A. N TARNOVSKY, and M. OLIVUCCI, Department of Chemistry and Center for Photochemical Sciences, Bowling Green State University, Bowling Green, OH 43403. The photochemical reaction pathways following the promotion of CF I and CH I into their lowest lying electronically excited states are reported. The pathways are mapped using the complete active space self-consistent field (CASSCF) method. The S to S transitions in both molecules are found to be n to sigma* type transitions. The relaxation of the electronically excited CF I * and CH I * molecules from the initially excited Frank-Condon (FC) region to the product wells on the ground-state potential energy surface are found to occur via conical intersections. The results from our computational investigations explain the selectivity of photoproduct formation previously observed in gas-phase experiments on one hand, where some obvious conclusions about the condensed-phase photochemistry of these molecules can also be drawn. Intermission 213 WJ07 10 min 3:45 THE FLUORESCENCE OF THE WURSTER’S BLUE RADICAL CATION IS CONTROLLED BY A CONICAL INTERSECTION ELENA N. LARICHEVA and MASSIMO OLIVUCCI, Department of Chemistry and Center for Photochemical Sciences, Bowling Green State University, Bowling Green, OH 43403, USA; JAKOB GRILJ and ERIC VAUTHEY, Physical Chemistry Department, University of Geneva, 1211 Geneva, Switzerland. The photochemistry and photophysics of a stable N,N,N’,N’- tetramethyl-p-phenylenediamine radical cation (commonly known as Wursters Blue) is the subject of current research interest as it represents an example of mixed valence (MV) compound. In this work we used ab initio CASSCF/CASPT2 quantum chemical calculations to map its first excited state (D ) potential energy surface in the gas-phase. According to the spectral data by Grilj et al., the fluorescence of Wursters Blue radical cation could only be observed at low temperatures (below 115K). In order to explain this behavior, the conical intersection space (IS) between the first excited (D ) and the ground state (D ) potential energy surfaces was mapped and characterized. The intrinsic reaction coordinate (IRC) scan, following the relaxation of the Wursters blue molecule from the D /D intersection space along the D potential energy surface, led to the ground state equilibrium structure. The energy barrier between the excited state energy minimum and the lowest lying conical intersection structure (CI) was calculated to be 3.1 kcal/mol. As a result, we concluded that this barrier was responsible for the observed temperature dependence of the fluorescence that disappears at temperatures above 115K due to the opening of a radiationless deactivation channel. WJ08 15 min 3:57 RELATIVISTIC JAHN-TELLER EFFECTS IN THE QUARTET STATES OF K AND RB : A VIBRATIONAL ANALYSIS OF THE 2 E 1 A ELECTRONIC TRANSITIONS BASED ON AB INITIO CALCULATIONS A. W. HAUSER, G. AUBÖCK, C. CALLEGARI and W. E. ERNST, Institute of Experimental Physics, Graz University of Technology, Petersgasse 16, A-8010 Graz, Austria. We apply the Multireference Rayleigh Schrödinger Perturbation Theory of second order to obtain the adiabatic potential energy surface of the 1 A electronic groundstate and the 2 E excited state of K and Rb . Both trimers show a typical E e Jahn-Teller distortion in their 2 E state, which is analyzed in terms of the relativistic Jahn-Teller effect theory. Linear, quadratic as well as spin-orbit coupling terms are extracted from the ab initio results and used to obtain theoretical spectra for a direct comparison to laser-induced fluorescence and magnetic circular dichroism spectra of alkali-doped helium nanodroplets [Auböck et al. J. Chem Phys. 129 114501 (2008)]. WJ09 15 min 4:14 COLLISIONAL QUENCHING OF OH A BY H AND N : DYNAMICAL OUTCOMES LOGAN P. DEMPSEY, TIMOTHY D. SECHLER, CRAIG MURRAY, MARSHA I. LESTER, Department of Chemistry, University of Pennsylvania, Philadelphia, PA 19104-6323; SPIRIDOULA MATSIKA, Department of Chemistry, Temple University, Philadelphia, Pennsylvania 19122-6014. The nascent OH X product state distributions arising from collisional quenching of electronically excited OH A by H and N have been determined using a pump-probe technique. For both collision partners, the majority of OH X products are observed in their lowest vibrational level, 1 , with significantly less population in 1 . The OH 1 products are generated with a substantial degree of rotational excitation, peaking around with H as the collision partner and with N . Complementary measurements of the branching fraction into OH X product states demonstrate that reaction is the dominant decay pathway for quenching of OH A by H , while nonreactive quenching is the dominant pathway for N . These observations are discussed in the context of theoretical calculations that examine the topography of the conical intersections which couple the electronically excited and ground state potential energy surfaces. The experimental observables are interpreted as dynamical signatures of nonadiabatic passage through the conical intersection regions responsible for quenching in both systems. 214 WJ10 15 min 4:31 EFFECTS OF ASYMMETRIC DEUTERATION ON THE ROTATIONAL LEVEL STRUCTURE OF JAHN-TELLER ACTIVE METHOXY RADICALS DMITRY G. MELNIK, MING-WEI CHEN, JINJUN LIU, a and TERRY A. MILLER, Laser Spectroscopy Facility, Department of Chemistry, The Ohio State University, 120 W. 18th Avenue, Columbus, Ohio 43210; ROBERT F. CURL, Department of Chemistry and Rice Quantum Institute, Rice University, Houston TX, 77005; C. BRADLEY MOORE, Department of Chemistry, University of California, Berkeley CA, 94720. Recently the high resolution microwave, LIF and SEP spectra of the methoxy isotopologues of the C symmetry, CH O, The data were globally fit to the effective rotational Hamiltonian (ERH), and the physical interpretation of its parameters has been given. In the present work we extend the studies of the rotationally resolved spectra of this Jahn-Teller active species to its asymmetrically substituted isotopologues. In these molecules the electronic wavefunction retains its threefold symmetry. Although the vibrational modes are no longer degenerate, the asymmetry induced by deuteration can be treated as a perturbation and the molecule can still be analyzed using theory similar to that which has been employed for the symmetric isotopologues. For this analysis we have used the ERH derived d for the internal axis system (IAS), whose E axis is parallel to the C-O bond. The form of the ERH has been extended to include the effects of the Jahn-Teller distortion on the rotational and spin-rotational Hamiltonian in IAS axis system with a nondiagonal rotational tensor. The microwave, LIF and SEP transitions were globally fit to the extended form of the ERH. The resulting parameters are compared to the corresponding values derived from the parameters of the symmetric species using the isotopic relationships. For the most signidicant parameters, the first and the second order contributions are calculated. The results of this analysis will be presented. CD O, and CH O have been analyzed b c . a present address: Laboratory of Physical Chemistry, ETH Zurich, Wolfgang-Pauli-Str. 10, 8093 Zurich, Switzerland M.-W.Chen, D.G.Melnik, and T.A.Miller, J.Chem.Phys, 130, 074302, (2009) c J.Liu, M.-W.Chen, D.G.Melnik, and T.A.Miller, J.Chem.Phys, 130, 074303, (2009) d D.Melnik, J.Liu, R.F.Curl, and T.A.Miller, Mol.Physics, 105, 529 (2007) b J.Liu, WJ11 15 min 4:48 STATE OF THE NITRATE RADICAL NO THE JAHN-TELLER (JT) EFFECT IN THE KANA TAKEMATSU, NATHAN EDDINGSAAS, and MITCHIO OKUMURA, Arthur Amos Noyes Laboratory of Chemical Physics, California Institute of Technology, Pasadena, California 91125; JOHN STANTON, Department of Chemistry, University of Texas at Austin, Austin, TX 78712. E of NO is poorly understood. A preliminary spectrum of the vibronically-allowed The JT effect in the transition, coupled with ab initio calculations, shows moderate JT activity in the state. Vibronic bands exhibit either static state. The picture of the state is however or dynamic JT distortions depending on the vibrational level of the upper incomplete. For example, in the E e =a a e manifold, while the splitting would provide a direct measure of the state by examining the hot JT strength, only the a levels have been observed. We have gained new insight into the bands of NO which access previously unobserved dark levels of the state. 215 RA. INFRARED/RAMAN THURSDAY, JUNE 25, 2009 – 8:30 AM Room: 160 MATH ANNEX Chair: NATHALIE PICQUE, CNRS Université de Paris-Sud, Orsay, France RA01 INFRARED SPECTRA OF TWO ISOMERS OF THE OCS-C H AND OCS-C D 15 min 8:30 MAHIN AFSHARI, M. DEHGHANY, J. N. OLIAEE, N. MOAZZEN-AHMADI, Department of Physics and Astronomy, University of Calgary, Calgary, AB T2N 1N4, Canada; A.R.W. MCKELLAR, Steacie Institute for Molecular Sciences, National Research Council of Canada, Ottawa, ON K1A 0R6, Canada. Spectra of the weakly-bound OCS-C H and OCS-C D complexes in the region of the OCS fundamental (2062 ) are observed in a pulsed supersonic slit jet expansion probed with a tunable diode laser. For each complex two bands are observed and assigned to the near parallel and the T-shape isomers. The ground state rotational and centrifugal distortion parameters were previousely determined from microwave studies. a b Analysis of the infrared spectra gives accurate band origins as well as rotational and centrifugal distortion parameters for the upper states. All four bands show a red shift with respect to the monomer band origin, with the T-shape isomers having about 5.4 larger shift than the corresponding near parallel isomers. a S.A. b S.A. Peebles and R.L. Kuczkowski, J. Phys. Chem. A 103, 3884 (1999). Peebles and R.L. Kuczkowski, Chem. Phys. Lett. 312, 357 (1999). RA02 15 min 8:47 INFRARED SPECTRA OF CARBONYL SULFIDE-ACETYLENE TRIMERS: OCS-(C H ) AND TWO ISOMERS OF (OCS) -C H MAHIN AFSHARI, M. DEHGHANY, J. N. OLIAEE, N. MOAZZEN-AHMADI, Department of Physics and Astronomy, University of Calgary, Calgary, AB T2N 1N4, Canada; A.R.W. MCKELLAR, Steacie Institute for Molecular Sciences, National Research Council of Canada, Ottawa, ON K1A 0R6, Canada. Spectra of acetylene-carbonyl sulphide trimers in the region of the OCS fundamental (2062 ) are observed using a tunable diode laser to probe a pulsed supersonic slit jet expansion. A previous microwave study of (OCS) - C H by Peebles and Kuczkowski a gave a nonplanar triangular twisted structure, which could be thought of as a polar OCS dimer plus a C H monomer lying above the dimer plane. In the present work, three infrared bands are analyzed. The first band clearly belongs to this previously known (OCS) -C H complex. The second band can be assigned as an isomer of (OCS) -C H having a similar structure, but with a nonpolar OCS dimer plus a C H monomer above the dimer plane. The third band is assigned to OCS-(C H ) . The rotational constants and dipole moment components of all three bands are consistent with barrel shape structures having C , C and C symmetries, respectively. a S.A. Peebles and R.L. Kuczkowski, J. Chem. Phys. 111, 10511 (1999). 216 RA03 15 min 9:04 FUNDAMENTAL AND TORSIONAL COMBINATION BANDS OF N O-C H AND N O-C D IN THE N O REGION M. DEHGHANY, MAHIN AFSHARI, J. N. OLIAEE, N. MOAZZEN-AHMADI, Department of Physics and Astronomy, University of Calgary, Calgary, AB T2N 1N4, CANADA; A.R.W. MCKELLAR, Steacie Institute for Molecular Sciences, National Research Council of Canada, Ottawa, ON K1A 0R6, CANADA. Spectra of the weakly-bound N O-C H and N O-C D complexes in the region of the N O fundamental band ( 2224 cm ) are observed in a pulsed supersonic slit jet expansion probed with a tunable diode laser. Two bands are analyzed for each complex: the fundamental (N-N stretch), and a combination involving the intermolecular torsional (out-of-plane bend) vibration. The resulting torsional frequencies are 44.37 and 40.01 cm for the C H and C D complexes, respectively. This represents the first observation of the N O-C D isotopomer, and the first direct determination of an intermolecular frequency for nitrous oxide - acetylene. RA04 INFRARED SPECTROSCOPY OF TWO ISOMERS OF THE OCS-CS COMPLEX 15 min 9:21 J. N. OLIAEE, M. DEHGHANY, MAHIN AFSHARI, N. MOAZZEN-AHMADI, Department of Physics and Astronomy, University of Calgary, 2500 University Dr., N.W., Calgary, Alberta T2N 1N4, Canada; A.R.W. McKELLAR, Steacie Institute for Molecular Sciences, National Research Council of Canada, Ottawa, Ontario, K1A 0R6, Canada. A second isomer of OCS-CS complex, with a nonplanar cross-shaped structure, has been studied for the first time by analysing an infrared band in the region of the OCS stretching vibration (2062 cm ). This isomer has C symmetry and the observed band consists of purely c-type rotational transitions. The ground state rotational parameters are found to be A=0.07306 cm , B=0.03325 cm and C=0.02879 cm , in good agreement with a previous semi-empirical calculation. a In addition, a hybrid band with a- and b-type rotational transitions has been assigned to be due to the known planar form of OCS-CS , as previously studied by microwave spectroscopy. a The spectra were recorded using a rapid-scan tunable diode laser spectrometer to probe a pulsed supersonic jet expansion. Calculations indicate that the planar isomer of OCS-CS is the lowest in energy, in contrast to CO -CS where the crossed form is believed to be the lowest. b a J. J. Newby, M. M. Serafin, R. A. Peebles and S. A. Peebles, Phys. Chem. Chem. Phys. 7, 487 (2005). C. Dutton, D. A. Dows, R. Eikey, S. Evans and R. A. Beaudet, J. Phys. Chem. A 102, 6904 (1998). b C. RA05 NEW INFRARED SPECTRA OF THE NITROUS OXIDE TRIMER 15 min 9:38 M. DEHGHANY, MAHIN AFSHARI, J. N. OLIAEE, N. MOAZZEN-AHMADI, Department of Physics and Astronomy, University of Calgary, Calgary, AB T2N 1N4, CANADA; A.R.W. MCKELLAR, Steacie Institute for Molecular Sciences, National Research Council of Canada, Ottawa, ON K1A 0R6, CANADA. Infrared spectra of N O trimers are studied using a tunable diode laser to probe a pulsed supersonic slit-jet expansion. A previous observation by R.E. Miller and L. Pedersen [J. Chem. Phys. 108, 436 (1998)] in the N O + combination band region ( 3480 cm ) showed the trimer structure to be noncyclic, with three inequivalent N O monomer units which could be thought of as an N O dimer (slipped antiparallel configuration) plus a third monomer unit lying above the dimer plane. The present observations cover the N O fundamental band regions ( 1280 cm ) and ( 2230 cm ). In the region, two trimer bands are assigned with vibrational shifts and other characteristics similar to those in the + region, but in the region all three possible trimer bands are observed. Relationships among the various bands such as rotational intensity patterns, vibrational shifts, and the properties of the related N O dimer, generally support the conclusions of Miller and Pedersen. Three trimer bands are also observed for the fully N-substituted species in the region, and these results should aid in detection of the as-yet-unobserved pure rotational microwave spectrum of the trimer. Finally, three combination bands involving the intermolecular van der Waals modes at 2253.7, 2255.5, and 2269.4 cm have been measured. The analyses of these bands and the identification of the nature of the intermolecular modes involved are currently underway. 217 Intermission RA06 15 min INFRARED SPECTROSCOPY OF 7-AZAINDOLE TAUTOMERIC DIMER AND ITS ISOTOPOMERS 10:20 HARUKI ISHIKAWA, HIROKI YABUGUCHI, YUJI YAMADA, AKIMASA FUJIHARA, KIYOKAZU FUKE, Department of Chemistry, Graduate School of Science, Kobe University, Nada-ku, Kobe 657-8501, Japan. 7-azaindole (7-AI) dimer is a very attractive species as a model system of neucleic-acid base pair. It is well-known that it exhibits the excited-state double proton transfer (DPT) reaction. In solution, the tautomeric dimer generated in the DPT reaction goes back to normal form in the electronic ground state. This ground-state inverse DPT reaction is not thoroughly studied, so far. Thus, we carry out infrared spectroscopy of the jet-cooled 7-AI tautomeric dimer and examine the possibility of the vibrational-excitation promoted inverse DPT reaction. In the IR spectrum of the 7-AI tautomeric dimer, a very strong and broad band appears at 2680 cm and is assigned as the anti-symmetric NH stretch mode. On the contrary, sharp bands around 3100 cm are assigned as the CH stretch modes. Such a large difference in the band profiles among these bands is related to the difference in the vibrational anharmonicity of these modes. To discuss the vibrational anharmonicity of the NH stretch mode and the relation to the DPT reaction, we have also recorded IR spectra of several deuterated dimers. Comparison among the IR spectra of isotopomers will be discussed in the paper. RA07 15 min 10:37 INFRARED SPECTRA OF M (2-AMINO-1-PHENYL ETHANOL)(H O) Ar (M=Na, K) AMY L. NICELY and JAMES M. LISY, Department of Chemistry, University of Illinois at UrbanaChampaign, Urbana, IL 61801. A balance of competing electrostatic and hydrogen bonding interactions directs the structure of hydrated gas-phase cluster ions. Because of this, a biologically relevant model of cluster structures should include the effects of surrounding water molecules and metal ions such as sodium and potassium, which are found in high concentrations in the bloodstream. The molecule 2-amino-1-phenyl ethanol (APE) serves as a model for the neurotransmitters ephedrine and adrenaline. The neutral APE molecule contains an internal hydrogen bond between the amino and hydroxyl groups. In the M (APE) complex, the cation can either interrupt the internal hydrogen bond or position itself above the phenyl group, leaving the internal hydrogen bond intact. The former is preferred based on DFT calculations (B3LYP/6-31+G*) for both K and Na across the entire range from 0-400K, but infrared photodissociation (IRPD) spectra indicate a preference for the latter configuration at low temperatures. The IRPD spectra of M (H O) and M (H O) Ar (M=Na, K) will be presented along with parallel DFT and thermodynamics calculations to assist with the identification of the isomers present in each experiment. RA08 15 min 10:54 SPECTROCSOPY AND STRUCTURE OF CATIONIC METAL CARBONYL SYSTEMS M(CO) M=V, CO N=1-10 ALLEN M. RICKS, and MICHAEL A. DUNCAN, University of Georgia, Athens Ga.. Metal carbonyl complexes are well known throughout inorganic chemistry and the carbonyl stretching vibration has historically served as a sensitive indicator of the electronic structure and bonding in these systems. Stable, fully coordinated metal carbonyl complexes have been extensively studied in the gas phase and are generally closed shell. Non-fully coordinated metal carbonyls are generally not closed shell and have been difficult to characterize in the gas phase due to their reactive nature. We present here the first systematic infrared spectroscopic studies of cationic metal carbonyl systems in the gas phase. The infrared spectra of Co(CO) and V(CO) for n=1-10 have been obtained using mass-selected infrared photodissociation spectroscopy. These measurements provide the coordination numbers, structures and spin states for these systems. Density Functional Theory calculations will also be presented in support of this work. 218 RA09 POLAR (ACYCLIC) ISOMER OF FORMIC ACID DIMER: RAMAN SPECTROSCOPY STUDY 10 min 11:11 ROMAN M. BALABIN, Department of Chemistry and Applied Biosciences, ETH Zurich, 8093 Zurich, Switzerland. Formic (methanoic) acid spectral range of 575–1150 cm has been studied by gas-phase Raman spectroscopy method. A weak Raman-active vibration of polar (acyclic) HCOOH dimer has been found at 8642.1 cm and assigned using quantum chemistry data. The temperature-dependence of intensity ratios of Raman lines was used to evaluate the thermodynamic parameters of polar dimer. Its experimental dimerization enthalpy (H) was found to be -8.60.2 kcal mol . Entropy of dimerization has been evaluated using theoretical (MP2) Raman scattering activities. Its value (S) is estimated as -362 cal mol K . The results are compared with the published experimental data and calculations. The presented results can be used for molecular dynamics simulations, hydrogen bond energy estimation, and analysis of CH O vapor density measurements. RA10 AR-PREDISSOCIATION SPECTROSCOPY OF PROTONATED IMIDAZOLE CLUSTERS 15 min 11:23 GEORGE H. GARDENIER, MARK A. JOHNSON, Sterling Chemistry Laboratory, Yale University, P.O Box 208107, New Haven, CT, 06520. We present Ar-predissociation spectra of cationic systems involving imidazole (Im): Im Ar, ImH Ar, Im H Ar, and Im H Ar in the range of 3000-3800 cm . We track the evolution of the C-H and N-H stretching vibrational frequencies as a function of the number of imidazole groups present in the cluster. The C-H stretching frequencies red-shift while the intensities of these transitions appear to equalize with the addition of imidazole molecules to the motif. Also, as the length of the proton-bound imidazole chain increases, we notice a blue shift in the frequency of the free (non-Ar-solvated) N-H stretch toward that of the analogous vibrational mode in neutral imidazole (3518 cm )a . The disappearance of Ar-bound N-H stretch when a second imidazole is added to the ImH Ar cluster strongly suggests a large-scale red shift of this feature as this proton becomes shared between two imidazole groups, illustrating the construction of an intermolecular proton-transfer scaffold. These data represent a microscopic model system for the ongoing effort to develop imidazolebased anhydrous PEM (Proton-Exchange Membrane) fuel cells. a M. Y. Choi, R. E. Miller, J. Phys. Chem. A 110, 30 (2006). RA11 15 min 11:40 INFRARED SPECTROSCOPY OF HYDRATED DOUBLY-CHARGED METAL IONS PRODUCED BY ELECTROSPRAY IONIZATION HARUKI ISHIKAWA, TORU EGUCHI, AKIMASA FUJIHARA, YUJI YAMADA, KIYOKAZU FUKE, Department of Chemistry, Graduate School of Science, Kobe University, Nada-ku, Kobe 657-8501, Japan. Until now, a large number of studies on the microscopic solvation effect of metal ion have been carried out. However, a very small number of spectroscopic studies on the doubly-charged metal ions are reported compared with that on the singly-charged ion. Since doubly-charged metal ions are highly energetic, electron- or proton- transfer reactions with solvent molecules should compete with the stabilization by solvation. Thus, we have carried out infrared spectroscopy of the hydrated doubly-charged metal ions. In the present study, we used the electrospray ionization method to produce the hydrated doubly-charged metal ions. The ions mass-separated by the first quadrupole mass filter are irradiated by IR laser light and then fragment ions are detected by the second quadrupole mass analyzer. In the case of Mg (H O) , a structure where one water molecule is hydrogenbonded to the 6-coordinated Mg is indicated by the IR spectrum. IR spectra of other systems will be presented in the paper. 219 RB. RADICALS AND IONS THURSDAY, JUNE 25, 2009 – 8:30 AM Room: 170 MATH ANNEX Chair: JINJUN LIU, ETH Zurich, Zurich, Switzerland RB01 15 min 8:30 STUDY OF TWO-PHOTON RESEONANT FOUR WAVE SUM MIXING IN XEON AND ITS COMPETITION WITH THE FOUR WAVE DIFFERENCE MIXING W. AL-BASHEER, Y. J. SHI, Department of Chemistry, University of Calgary, Calgary, Alberta, T2N 1N4. The two-photon resonant four wave sum- and difference-mixing in Xe gaseous medium was studied by subjecting a variety of molecular samples, including acetone, furan, triethylamine (TEA), and dimethylsilacyclobutane (DMSCB), to the laser sources produced from the four wave mixing processes for ionization. Ionization of acetone-h6, acetone-d6, furan-h4, furan-h4, and DMSCB samples showed similar behaviour. It is demonstrated that in a vacuum ultraviolet (VUV) spectral region of 103 - 109 nm four-wave sum mixing in Xe can only occur in ten discontinued regions, all of which are to the blue of a Xe atomic transition. Study of the TEA sample with its ionization potential lower than the photon energy of the VUV radiation from the difference mixing illustrated the competition between the sum- and difference-mixing occurring simultaneously in the Xe gas cell. RB02 15 min 8:47 INFRARED SPECTROSCOPY OF H O N ) (n=1,2,3) COMPLEXES T. CHENG, B. BANDYOPADHYAY, M. A. DUNCAN, Department of Chemistry, University of Georgia, Athens, GA 30602-2556. Gas phase H O (N ) (n=1,2,3) complexes are produced in a pulsed electrical discharge supersonic expansion source. Infrared spectra of the cold species are obtained via infrared photodissociation spectroscopy. Theoretical investigations have been employed to probe the structures of these complexes. The infrared spectroscopy (2400-3800 cm ) of these complexes will be discussed. For the n=1 complex, the broad peak around 2785 cm is attributed to the shared proton stretch. Partially resolved rotational structure is also observed in the water stretch region. Rotational simulation of the spectrum reproduced the experimental spectrum with the rotational temperatures J=40K and K=25K. The rotational structure is quenched for the n=2 and 3 complexes as the free rotation of the water is hindered due to the presence of nitrogen. RB03 INFRARED SPECTROSCOPY OF PROTONATED WATER-BENZENE CLUSTERS 15 min 9:04 T. CHENG, B. BANDYOPADHYAY, M.A. DUNCAN, Department of Chemistry, University of Georgia Athens, GA 30602. Mixed protonated clusters of water and benzene are created via arc discharge in a supersonic molecular beam cluster source. Infrared spectra are obtained via infrared photodissociation spectroscopy utilizing argon tagging. Infrared spectroscopy (1000 cm to 4500 cm ) of these mixed clusters H (H2O) (Bz) (x=1,3, y=1-2) tagged with argon is employed to investigate the structures of these clusters, particularly with regards to the location of the proton. Studies as a function of cluster size investigate solvation of the proton. In the 1,1 cluster, a proton asymmetrically shared between the water and benzene is observed, with the proton closer to water even though benzene has the higher proton affinity. Clusters with multiple waters prefer to form protonated water clusters, with an attached neutral benzene. 220 RB04 15 min 9:21 HALF-SANDWICH COMPLEXES OF GROUP III (Sc, Y, and La) METALS WITH CYCLOOCTATERAENE SUDESH KUMARI, JUNG SUP LEE, and DONG-SHENG YANG, Department of Chemistry, University of Kentucky, Lexington, KY 40506-0055. 1,3,5,7 – Cyclooctatetraene (COT, C H ) is one of the most versatile ligands used in organometallic chemistry, with coordination modes of F , F , F , and F . COT is non-aromatic with a tub conformation; however, its dianion (C H ) is aromatic and planar. In this work, we have studied group III M-COT (M = Sc, Y, and La) 1:1 complexes using pulsed field ionization - zero electron kinetic energy (ZEKE) photoelectron spectroscopy and density functional theory. The ZEKE spectra of these complexes show a strong 0-0 transition and a major metal-ligand stretching progression. The ionization energies are measured to be 42261(5), 40747(5), and 36641(5) cm ; and the M -COT stretching frequencies are 338, 300, and 278 cm for the triad. The ionization energies of the metal complexes decrease down the group as expected from those of the bare metal atoms. The metal-ligand stretching frequencies decrease with increasing the mass of the metal atoms. In coordination with theory, the neutral and ionized complexes are determined to be in C point group, with M/M in F binding to the planar COT; the observed transition is assigned to A A . The conformation change of the COT molecule upon metal coordination is associated with the metal to ligand electron transfer and metal-ligand orbital interaction. RB05 ROTATIONAL CONFORMERS OF GROUP VI (Cr, Mo, and W) METAL BIS(TOLUENE) PLEXES 15 min 9:38 COM- JUNG SUP LEE, SUDESH KUMARI, and DONG-SHENG YANG, Department of Chemistry, University of Kentucky, Lexington, KY 40506-0055. Transition metal bis(arene) sandwich complexes may adopt eclipsed or staggered conformations due to the aromatic ring rotations about the metal-arene axis. a b In this study, the group VI (Cr, Mo, and W) metal bis(toluene) complexes are synthesized in a laser-ablation molecular beam source, and their rotational conformers are identified by pulsed-field-ionization zero-electron-kinetic-energy (ZEKE) spectroscopy. For Cr-bis(toluene), the ZEKE spectrum shows three distinctive vibrationless (0-0) transitions between the ground electronic states of the neutral and ionic complexes at 42739(5), 42745(5), and 42805(5) cm , corresponding to ionization energies of Æ, Æ /Æ , and Æ rotamers. In addition, the spectrum exhibits metal-toluene bending (164, 180, 196, and 223 cm ) and stretching (278 and 291 cm ) frequencies of these rotamers. The ground electronic states of the Æ and Æ rotamers are A (C ) and A (C ) in the neutral form and A (C ) and A (C ) in the ionized form, respectively. For the Æ and Æ rotamers, the ground states of the neutral molecules are A (C ), and those of the corresponding ions are A (C ). Through the variation of the molecular beam conditions, the eclipsed conformer ( Æ ) is determined to be more stable than the staggered ones ( Æ , Æ , and Æ ). Similarly, multiple conformers are identified for the Mo and W complexes. a B.S. b S.Y. Sohnlein, S. Li, and D.S. Yang, J. Chem. Phys. 123, 214306 (2005); B.S. Sohnlein and D.S. Yang, J. Chem. Phys. 124, 134305 (2006) Ketkov, H.L. Sezle, and F.G.N. Cloke, Angew. Chem. Int. Ed. 46, 7072 (2007) and references therein. Intermission 221 RB06 15 min 10:10 KINETIC AND THERMODYNAMIC STUDIES OF GASEOUS METALLO-ORGANIC CATIONIC COMPLEXES S. JASON DEE, VANESSA A. CASTLEBERRY, OTSMAR J. VILLARROEL, IVANNA E. LABOREN, SARAH E. FREY and DARRIN J. BELLERT, Department of Chemistry and Biochemistry, Baylor University, Waco, Texas, 76798. The construction of a custom fabricated photodissociation spectrometer permits the determination of thermodynamic properties (activation energies), reaction rates, and mechanistic details of bare metal cation mediated ! -bond activation in the gas phase. Specifically, the products and rates resulting from the unimolecular decomposition of the Ni Acetaldehyde adduct are monitored after absorption of a known amount of energy. The two dissociative products which are observed in high yield are Ni and Ni CO. The Ni CO fragment ion could result from the activation of a C-C ! -bond or from the activation of a C-H ! -bond. The rate constant for the decarbonylation of Ni Acetaldehyde was approximately 30 percent greater than that of the rate constant for the decarbonylation of Ni Acetone. For the decarbonylation of Ni Acetone, there needs to be a methide shift, whereas in the decarbonylation of Ni Acetaldehyde one could have C-C insertion followed by an aldhyde H-shift. The rate-limiting step of the decarbonylation process will be discussed. RB07 15 min 10:27 A STUDY OF THE HYDROXYCYCLOHEXADIENYL RADICAL ABSORPTION USING TIME-RESOLVED RESONANCE RAMAN SPECTROSCOPY DEANNA M. O’DONNELL, G.N.R. TRIPATHI, NICOLE R. BRINKMANN, Department of Chemistry and Radiation Laboratory, University of Notre Dame, Notre Dame, IN 46545. Thus far there has been little understanding of the vibrational spectra, structure and electronic absorption of hydroxycyclohexadienyl radicals in water. They are primary chemical species formed on interaction of radiation with aqueous solutions containing aromatic molecules. We have applied time- resolved resonance Raman (TR-RR) spectroscopy to structurally identify isomers of cyclohexadienyl radicals formed in the pulse radiolysis, using aqueous benzoate solutions as a model system. An early ESR study ((Eiben, K; Fessenden, R.W.; J. Phys. Chem. 1971, 75, 1186-1201) has shown that a mixture of three benzoate hydroxycyclohexadienyl radical isomers: ortho-, meta- and para- are formed upon electron irradiation of N O saturated benzoate solution. Their collective transient absorption is believed to exhibit a single broad band in the near UV region (4 = 330 nm, G = 3800 M cm ). To extract the single isomeric contribution to this collective absorption, we applied TR-RR at various wavelengths within the broad transient absorption range looking for the characteristic indication of each individual isomer. Raman signals of various para-substituted benzoates were also collected to aid in the vibrational studies of the aforementioned benzoate hydroxycyclohexadienyl radicals. 222 RB08 PHOTOELECTRON SPECTROSCOPY OF SUBSTITUTED PHENYLNITRENES 15 min 10:44 NELONI R. WIJERATNE, MARIA DA FONTE and PAUL G. WENTHOLD, Department of Chemistry, Purdue University, West Lafayette, IN 47907-2084. Nitrenes are unusual molecular structures with unfilled electronic valences that are isoelectronic with carbenes. Although, both can be generated by either thermal or photochemical decomposition of appropriate precursors they usually exhibit different reactivities. In this work, we carry out spectroscopic studies of substituted phenylnitrene to determine how the introduction of substituents will affect the reactivity and its thermochemical properties. All studies were carried out by using the newly constructed time-of-flight negative ion photoelectron spectrometer (NIPES) at Purdue University. The 355 nm photoelectron spectra of the o-, m-, and p-chlorophenyl nitrene anions are fairly similar to that measured for phenylnitrene anion. All spectra show low energy triplet state and a high energy singlet state. The singlet state for the meta isomer is well-resolved, with a well defined origin and observable vibrational structure. Whereas the singlet states for the ortho and para isomers have lower energy onsets and no resolved structure. The isomeric dependence suggests that the geometry differences result from the resonance interaction between the nitrogen and the substituent. Quinoidal resonance structures are possible for the open-shell singlet states of the o- and p-chlorinated phenyl nitrenes. The advantages of this type of electronic structures for the open-shell singlet states is that the unpaired electrons can be more localized on separate atoms in the molecules, minimizing the repulsion between. Because the meta position is not in resonance with the nitrenes, substitution at that position should not affect the structure of the open-shell singlet state. The measured electron affinities (EA) of the triplet phenylnitrenes are in excellent agreement with the values predicted by electronic structure calculations. The largest EA, 1.82 eV is found for the meta isomer, with para being the smallest, 1.70 eV. RB09 Post-deadline Abstract – Original Abstract Withdrawn 15 min 11:01 ON THE MAGNITUDE OF THE NONADIABATIC ERROR FOR HIGHLY COUPLED RADICALS JF STANTON, Department of Chemistry and Biochemistry, University of Texas at Austin, Austin, TX 78712. A review is given of recent advances in the construction of (quasi)diabatic model Hamiltonians and their application to analyzing the spectroscopy of molecules with strong vibronic coupling. A numerical application to the vibronic levels of the BNB radical below 0.6 eV is presented, together with corresponding adiabatic (quantum chemistry) calculations. The agreement with the experimental levels is nearly quantitative with the model Hamiltonian, attesting to the power of the approach. On the contrary, it is also revealed that the magnitude of the nonadiabatic contributions to the zero-point energy and the lowest fundamental frequency of the coupling mode are considerably larger than expected, at least by your narrator. RB10 15 min 11:18 CONFORMATIONS OF CATIONIZED PEPTIDES. DETERMINATION OF LIGAND BINDING GEOMETRIES BY IRMPD SPECTROSCOPY ROBERT C. DUNBAR, Chemistry Department, Case Western Reserve Univ., Cleveland, OH 44106; JEFFREY STEILL, JOS OOMENS, FOM Institute for Plasma Physics, Nieuwegein, Netherlands; NICK C. POLFER, Chemistry Department, University of Florida, Gainesville, FL 32611. Spectroscopic study of the conformations of metalated amino acids has mapped out in some detail the preferences for canonical (charge solvated) versus zwitterionic (salt bridge) conformations. Corresponding studies of larger peptides are now possible. Here are described results for several singly and doubly charged metal ions with dipeptides and tripeptides. Factors including ion charge, size of cation, and side chain identity and sequence are found to be conformational determinants. IRMPD spectra of the ions were acquired by irradiating the cell with infrared light from the FELIX free electron laser at wavelengths in the approximate range 500 to 1900 cm . 223 RB11 15 min 11:35 PHOTODAMAGE TO ISOLATED MONONUCLEOTIDES: PHOTODISSOCIATION SPECTRA AND FRAGMENT CHANNELS JESSE C. MARCUM, AMIT HALEVI, J. MATHIAS WEBER, JILA, NIST, and Department of Chemistry and Biochemistry, University of Colorado, Boulder, Co 80309. We have obtained photodepletion and photofragment action spectra on the UV-photodissociation of deprotonated 2’deoxyribonucleobase-5’-monophosphates with adenine, cytosine, guanine and thymine as nucleobases. We observe the same anionic fragments as in earlier experiments on collision-induced dissociation, although their relative intensities are quite different, especially with respect to the abundance of the deprotonated base anions. This behavior suggests a different sampling of phase-space prior to dissociation compared to collision-induced dissociation, where every energetically accessible part of phase space can be visited. The fragment channels correspond to loss of genetic information by cleavage of the CN glycosidic bond and to strand breaking by severing the phosphatesugar link. Comparison of the photodissociation spectra with UV absorption spectra of aqueous solutions of the same species reveals small solvatochromic shifts. 224 RC. MICROWAVE THURSDAY, JUNE 25, 2009 – 8:30 AM Room: 1000 McPHERSON Lab Chair: LUCY ZIURYS, University of Arizona, Tucson, Arizona RC01 THE DISCOVERY OF BRIDGED HPSI BY ROTATIONAL SPECTROSCOPY 15 min 8:30 M. C. MCCARTHY, V. LATTANZI, P. THADDEUS, Harvard-Smithsonian Center for Astrophysics, 60 Garden St., Cambridge, MA 02138, and School of Engineering & Applied Sciences, Harvard University, 29 Oxford St., Cambridge, MA 02138; D. T. HALFEN, L. M. ZIURYS, Department of Chemistry, Department of Astronomy, and Steward Observatory, University of Arizona, Tucson, AZ, 85721; SVEN THORWIRTH, MaxPlanck-Institut für Radioastronomie, Auf dem H ügel 69, 53121 Bonn, Germany; AND J. GAUSS, Institut für Physikalische Chemie, Johannes Gutenberg-Universit ät Mainz, Jakob-Welder-Weg 11, 55128 Mainz, Germany. The pure rotational spectrum of bridged HPSi, the isomer calculated to be the global minimum of the [H,Si,P] potential energy surface, has been measured using a combination of Fourier transform microwave spectroscopy (FTM) and millimeter/submillimeter direct absorption techniques. In the centimeter-wave band, the lowest two -type rotational transitions in the ' ladder were measured for the normal isotopic species, HP Si, HP Si, and DPSi in a supersonic molecular beam discharge source using a dilute mixture of SiH (or SiD ) and PH . The experimental work was initially guided by theoretical structures and rotational constants obtained at the CCSD(T)/cc-pwCVQZ level of theory and zero-point vibrational corrections at the CCSD(T)/cc-pV(T+)Z level. Following detection of HPSi in the FTM experiment, theoretical best estimates for the structure and the rotational constants were obtained using additivity and extrapolation techniques. On the basis of the centimeter-wave data, the millimeter/submillimeter spectrum of normal HPSi was subsequently measured between 287 and 421 GHz, including K components from K = 0 to 5, using a combination of gas-phase elemental phosphorus, H , and SiH diluted in argon through an AC glow discharge. From the combined data set, precise spectroscopic constants have been determined using a standard asymmetric top Hamiltonian; all of the measured constants are in excellent agreement with those predicted from theory. From the available data, an unusual H-bridged structure has been derived in which the H atom is situated slightly closer to the P atom. The geometry of HPSi is in remarkable contrast to that of the C and/or N anaogues, i.e. HCN/HNC, HCP, and HNSi which are all linear. 225 RC02 15 min 8:47 FOURIER TRANSFORM MICROWAVE SPECTROSCOPY AND MOLECULAR STRUCTURE OF THE 1,1DIFLUOROETHYLENE–HF COMPLEX MARK D. MARSHALL, HELEN O. LEUNG, TASHA L. DRAKE, TADEUSZ PUDLIK, NAZIR SAVJI, and DANIEL W. McCUNE, Department of Chemistry, Amherst College, P.O. Box 5000, Amherst, MA 010025000. The rotational spectra of six isotopomers of 1,1-difluoroethylene–HF have been collected in the 7 - 22 GHz region with a Fourier transform microwave spectrometer. These include the most abundant isotopomer, its DF counterpart, and four singly substituted C species in natural abundance. Both - and *-type transitions have been observed for all species. In addition, the hydrogen-fluorine spin-spin coupling interaction in the HF subunit for CH CF –HF and the deuterium nuclear quadrupole coupling interaction in CH CF –DF have been observed and analyzed. The rotational constants are consistent with a planar complex, with the two subunits interacting through a hydrogen bond formed between the H atom of HF and an F atom in 1,1-difluoroethylene and via a secondary interaction between the F atom in HF and the H atom located cis to the hydrogen-bonded F atom in 1,1-difluoroethylene. The rotational constants, hyperfine coupling constants, and results from the analogous complex, CH CF –HCCH,a are combined to determine the structural parameters of 1,1difluoroethylene–HF and 1,1-difluoroethylene–DF, which are found to be slightly different. a H. O. Leung and M. D. Marshall, J. Chem. Phys. 125, 154301 (2006). RC03 THE STRUCTURE OF THE TRANS-1,2-DIFLUOROETHYLENE–HF COMPLEX 15 min 9:04 HELEN O. LEUNG, MARK D. MARSHALL, and BRENT K. AMBERGER, Department of Chemistry, Amherst College, P.O. Box 5000, Amherst, MA 01002-5000. To understand the effects of fluorine substitution in ethylene on intermolecular interactions, we have expanded our work on the Fourier transform microwave spectroscopy of trans-1,2-difluoroethylene–HF reported last year a to include six isotopomers: the most abundant, its DF counterpart, and four singly substituted C species in natural abundance. The spectra are analyzed with the inclusion of the hydrogen-fluorine spin-spin coupling interaction in the HF subunit, or for those complexes containing DF, the deuterium nuclear quadrupole coupling interaction. Analysis of the rotational and hyperfine constants gives a planar complex, with a hydrogen bond formed between HF and one of the F atoms in trans1,2-difluoroethylene. As with similar complexes, the hydrogen bond bends to allow the F atom in HF to interact with an H atom in the ethylene subunit. Although there are two possible sites for this secondary interaction, namely the H atoms vicinal and geminal to the hydrogen bonded F atom, only the interaction involving the former H atom is observed. The structure of this complex will be compared with those of similar complexes with different patterns of F atom substitution in the ethylene subunit. a B. K. Amberger, H. O. Leung, and M. D. Marshall, The 63rd OSU International Symposium on Molecular Spectroscopy, Talk WF04 (2008). 226 RC04 15 min 9:21 THE IMPACT OF LONG RANGE INTERACTIONS ON LOW TEMPERATURE PRESSURE BROADENING: THE CASE OF HE–OCS K. N. SALB, D. R. WILLEY, Department of Physics, Allegheny College, Meadville, PA 16335. We address a persistent and troubling discrepancy between low temperature pressure broadening measurements and the predictions of high quality, experimentally-confirmed potential surfaces. In particular we focus on recent low temperature (4-30 K) pressure broadening measurements of OCS broadened by He a and the corresponding predictions of a recent HeOCS potentialbsurface which gives excellent agreement with observed rotational transitions of the bound complex, yet predicts cross sections which diverge sharply from experiment at temperatures below 10 K. By modifying the long range, asymptotic portion of the potential, forcing the potential to approach zero more rapidly, we are able to significantly improve agreement with the low temperature data. The modifications are made well out from the global minimum and thus should have a minimal impact on the calculated energies of the bound complex. Two modifications were tried, an isotropic version and an anisotropic version. While both versions gave improved agreement with the pressure broadening results, the isotropic modification was more successful at reproducing the experimental measurements. a K. b J. A. Ross & D. R. Willey, J. Chem. Phys. 122, 204308 (2005) M. M. Howson & J. M. Hutson, J. Chem. Phys 115, 5059 (2001) RC05 A MICROWAVE INVESTIGATION OF THE CO -PYRIDINE VAN DER WAALS COMPLEX 15 min 9:38 J. L. DORAN, B. J. HON, and K. R. LEOPOLD, Department of Chemistry, University of Minnesota, Minneapolis, MN 55455.. Rotational spectra of the NC H -CO dimer and four isotopologs have been observed using Fourier transform microwave spectroscopy. Analysis of the rotational and quadrupole coupling constants will be presented. Preliminary structural analysis indicates the complex is planar; the CO axis is perpendicular to the C axis of pyridine with a C-N van der Waals ˚ . This complex provides the first step in the microsolvation of an organic solute using CO as a bond length of 2.83 solvent and therefore may be useful in understanding solute-solvent interactions in supercritical CO . RC06 ROTATIONAL SPECTRA AND STRUCTURE OF PHENYLACETYLENE- COMPLEX 15 min 9:55 MAUSUMI GOSWAMI and E. ARUNAN, Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore 560012, India. Rotational Spectra of phenylacetylene- , phenylacetylene- , phenylacetylene- , phenylacetylene- , have been measured. The spectra were recorded using a Balle-Flygare type PNFT Microwave spectrometer[1]. Helium was used as a carrier gas for these measurements. Both ‘’ and ‘*’ dipole transitions have been observed. For the parent isotopomer, all the transitions are split into two. The rotational spectra of phenylacetylene- indicate that the splitting is due to the interchange of equivalent hydrogens of unit in the complex. The measured rotational constants of the parent species are %HE , %HE , %HE for the stronger series and %HE , %HE , %HE for the weaker series. The constants derived from the experiments confirm a structure where is placed perpendicular to the plane of the phenylacetylene molecule. This study reveals that the binding of and to the phenylacetylene molecule is very different. Microwave spectroscopic investigations confirmed that prefers to be in plane of the phenylacetylene, donating one of its hydrogen to the acetylenic $ cloud while the oxygen of is involved in a secondary interaction forming C-H—O hydrogen bond with the ring hydrogen ortho to the acetylenic group[2]. 1. Arunan et al.Current Science,82(2002)533. 2. TA04,63rd International Symposium on Molecular Spectroscopy,Columbus, June 16-20, 2008. 227 RC07 10 min 10:12 ROTATIONAL SPECTROSCOPIC AND THEORETICAL INVESTIGATIONS ON BENZENE-ETHYLENE COMPLEX AISWARYA LAKSHMI P. and E. ARUNAN, Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore 560012, India. Theoretical studies and condensed phase experimental studies point towards a $ stacked structure for benzene dimer, for which experimental evidence has not been found yet. This structure has no dipole moment and hence microwave spectroscopy can not be used. Benzene and ethylene can dimerise to give $ stacked complex which will have a net dipole moment. Rotational spectroscopic technique can be used to detect this $ stacked structure, if present, in the gas phase. Depending upon the nature of interaction, in addition to the $ stacked structure, other geometries are also possible where either benzene or ethylene can act as hydrogen bond donor. Theoretical investigations led to five different structures including the $ stacked one. Pulsed Nozzle Fourier Transform Microwave Spectrometer has been used to study the rotational spectrum of the benzene-ethylene complex, with helium as the carrier gas. A total of 24 ‘’ dipole transitions were observed. Out of these 24 transitions, 20 lines were fitted to the structure with as the hydrogen bond donor. In the observed transitions the ' lines show doubling. The line centres of the ' doublets were used along with ' transitions for the fitting. The fitted rotational constants are, %;E , %HE , %HE . Search and assignments for and complexes are in progress. Intermission RC08 MICROSOLVATION OF BUILDING BLOCKS 15 min 10:40 V. VAQUERO, I. PENA, S. MATA, J. C. L ÓPEZ, and J. L. ALONSO, Grupo de Espectroscopı́a Molecular (GEM), Departamento de Quı́mica Fı́sica y Quı́mica Inorgánica, Facultad de Ciencias, Universidad de Valladolid, E-47005 Valladolid, Spain. Laser ablation molecular beam Fourier transform microwave spectroscopy LA-MB-FTMW has provided the first observation of the rotational spectra of the glycine-H O complex.a As a continuation of this work we present the study of monohydrated complexes of alanine, uracil and thymine and the first observations of the dihydrated clusters glycine-(H O) and alanine-(H O) . For the microsolvated amino acids only the conformer with cis-COOH configuration and bifurcated NH O=C H-bond has been observed. Both alanine-H O and glycine-H O have similar shapes: the water molecule being bonded through two O-H O hydrogen bonds to the carboxylic group of the amino acid. The dihydrated clusters have also comparable structures where the two water molecules form a cycle with the COOH group through sequential H-bonds. The rotational spectra of uracyl-H O and thymine-H O show the same complexity than those of the bare molecules b c due to the hyperfine structure of two quadrupolar N atoms. The detected conformers show comparable structures with the water molecule bonded through two N-H O and O-H O=C hydrogen bonds to the N bases. The structure of hydrogen bond has been investigated by isotopic substitution. a J.L. Alonso, E.J. Cocinero, A. Lesarri, M.E. Sanz and J.C. López, Angew. Chem. 45, 3471 (2006) Vaquero, M.E. Sanz, J.C. López and J.L. Alonso,J. Phys. Chem. A111, 3443 (2007) c J.C. López, M.I. Peña, M.E. Sanz and J.L. Alonso, J. Chem. Phys. 126, 191103 (2007) b V. 228 RC09 10 min 10:57 SIZING THE UBBELHODE EFFECT: THE ROTATIONAL SPECTRUM OF TERT-BUTYLALCOHOL DIMER SHOUYUAN TANG, College of Bioengineering, ChongQing University, ChongQing, 400044, P. R. China; IRENA MAJERZ, Faculty of Chemistry, University of Wroclaw, Joliot-Curie 14, 50-383 Wroclaw, Poland; WALTHER CAMINATI, Dipartimento di Chimica ”G. Ciamician” dell’Universit à, Via Selmi 2, I40126 Bologna, Italy. We measured the molecular beam Fourier transform microwave spectra of four isotopic species of of the dimer of tert-butanol, that is C H -OH O(H)-C H , C H -OH O(D)-C H , C H -OD O(H)-C H , and C H -OD O(D)C H . We observed that the H – D isotopic substitution of the hydroxylic hydrogen participating in the O-H O Hydrogen bond in the tert-butanol dimer produces an increase of the B and C rotational constants, according to the shrinkage of the O O distance, underlying and sizing the associated Ubbelhode effect. a The conformation and structure of the complex, and an estimation of the Ubbelhode effect have been obtained by combining the experimental data with the results of MP2/6-311++G** ab initio calculations. a A. R. Ubbelhode, K. J. Gallagher, Acta Crystallogr. , 1955, 8, 71 RC10 15 min 11:09 CALCULATIONS AND GAS PHASE MEASUREMENTS OF THE COMPLEX FORMED WITH FERROCENE AND HCL ADAM M. DALY, STEPHEN G. KUKOLICH, DEPARTMENT OF CHEMISTRY, UNIVERISTY OF ARIZONA, TUCSON, AZ. Calculations for the Ferrocene and HCl complex using MP2/6-31+G(d) on C,H,Cl and Hay-Wadt VDZ (n+1) core potential on Fe indicate preferred binding of HCl along the b-axis of ferrocene, with hydrogen pointing to Iron. Several transitions have been measured using a Flygare-Balle microwave spectrometer in the 4-12 MHz range showing chlorine quadrupole splitting consistent with the complex. The calculated structure and quadrupole coupling constants will be presented with recent progress on measurements. RC11 15 min 11:26 PURE ROTATIONAL AND ULTRAVIOLET-MICROWAVE DOUBLE RESONANCE SPECTROSCOPY OF TWO WATER COMPLEXES OF PARA-METHOXYPHENYLETHYLAMINE JUSTIN L. NEILL, MATT T. MUCKLE, and BROOKS H. PATE, Department of Chemistry, University of Virginia, Charlottesville, VA 22904; RYAN G. BIRD and DAVID W. PRATT, Department of Chemistry, University of Pittsburgh, Pittsburgh, PA 15260. The neurotransmitter p-methoxyphenylethylamine (pMPEA) has been well-studied by ultraviolet and microwave spectroscopy. Seven conformers of this molecule have been assigned in total, showing good agreement with ab intio rotational constants, relative dipole moments, N quadrupole coupling constants, and relative energies. In this talk, we present the assignment of two conformations of the water complex of pMPEA by chirped pulse Fourier transform microwave spectroscopy. These two structures are the two lowest energy conformations of the pMPEA monomer, with a water molecule donating a hydrogen bond to the nitrogen atom. Good agreement between ab initio and experimental parameters is observed. In addition, ultraviolet-microwave double resonance spectra have been collected on a Balle-Flygare type cavity to determine the electronic band origins of these complexes, confirming that these water clusters are the same as those previously observed by Unamuno et al. a a I.Unamuno, J.A.Fernández, C.Landajo, A.Longarte, F.Castaño, Chem. Phys. 271 (2001) 55-69. 229 RC12 15 min A MICROWAVE AND AB INITIO STUDY OF THE NITRIC ACID - TRIMETHYLAMINE COMPLEX 11:43 GALEN SEDO, Department of Chemistry, The University of Manitoba, Winnipeg, MB Canada R3T 2N2; KENNETH R. LEOPOLD, Department of Chemistry, The University of Minnesota, Minneapolis, MN 55455. The microwave spectrum of the gas phase nitric acid - trimethylamine complex has been observed using Fourier transform microwave spectroscopy. The experimental rotational constants and (CH ) N-HNO isotope shifts are consistent with a complex in which the nitric acid proton forms a hydrogen bond to the nitrogen of the amine, similar to the experimentally determined structure of H N-HNO a . Analysis of the hyperfine structure in both the parent and (CH ) N-HNO spectra made it possible to determine, unambiguously, the quadrupole coupling constants of the N nuclei in both the nitric acid and trimethylamine moieties. Ab initio calculations, using the MP2/6-311++G(2df,2pd) level of theory and basis set, have been performed and are in quantitative agreement with the available experimental data. Both the experimentally determined quadrupole coupling constants and the ab initio structure have been used to assess the degree of proton transfer occurring in the nitric acid - trimethylamine complex. These results will be compared to those obtained for the H N-HNO and HNO -(H O)n [n = 0 - 3] complexes and discussed in terms of how binding partner basicity and the number of solvent molecules influence the incipient ionization of nitric acid moiety. a M. E. Ott, and K. R. Leopold, J. Phys. Chem. A 1999, 103,1322-1328 RC13 THE FREE JET MICROWAVE SPECTRUM OF 2-PHENYLETHYLAMINE-WATER 10 min 12:00 SONIA MELANDRI, B. MICHELA GIULIANO, ASSIMO MARIS and WALTHER CAMINATI, Dipartimento di Chimica Ciamician, Universit à di Bologna, via Selmi 2,40126 Bologna, Italy. 2-Phenylethylamine (PEA) is the parent structure for a variety of important compounds including dopamine, tyrosine, anphetamine and adrenaline. Due to the flexibility of the side chain, the conformational hypersurface of the isolated molecule contains several minima at relatively low energy. The conformational surface was studied by various spectroscopic and theoretical techniques and four of the five stable conformers were detected. a The most stable conformers observed in isolated conditions are those in which the methylene side chain is folded into a gauche structure and the amino hydrogen is oriented towards the aromatic ring to form a weakly hydrogen bonded structure, while in the less stable conformers the amino group is in the anti position, thus the energy difference between the gauche and anti conformers (ca 4 kJ mol ) represents the energy associated with this weak interaction. Since bioactive molecules can be found in different environments including aqueous media and rotational spectroscopy coupled with high level ab initio calculations gives the most detailed structural picture, we studied the free jet microwave spectrum of the adducts formed between PEA and water in the region 60-78 GHz. The dominant spectrum is that of the 1:1 adduct of PEA and water where PEA is in its most stable gauche conformation and the water molecole is bound to the nitrogen lone pair. The orientation of the water molecole is such that the oxygen atom is closest (ca 2.5 Å) and equidistant from the ring and chain hydrogen atoms. The experimental data were complemented by ab initio calculations at the MP2/6311++G** level of theory; several stable conformations of the PEA-W have been characterized and the observed structure corresponds to the global minimum. The bonding of water seems to affect only slightly the structure of isolated PEA and the main structural parameters of the flexible amino side chain remain basically unaltered. Some lines still remain unassigned in the spectrum and we are hoping to assign them to a second conformational species of PEA-W. a (a) S. J. Martinez, J. C. Alfano and D. H. Levy J. Mol. Struct. 158 82 1993. (b)P. D. Godfrey,L. D. Hatherley and R. D. Brown J. Am. Chem. Soc. 117 8204 1995. (c)S. Sun and E. R. Bernstein J. Am. Chem. Soc. 118 5086 1996. (d) J. A. Dickinson, M. R. Hockridge, R. T. Kroemer, E. G. Robertson, J. P. Simons, J. McCombie and M. Walker J. Am. Chem. Soc. 120 2622 1998. (e) J. C. Lopez, V. Cortijo, S. Blanco and J. Alonso PCCP 9 4521 2007. 230 RD. MINI-SYMPOSIUM: CAVITY ENHANCED SPECTROSCOPY THURSDAY, JUNE 25, 2009 – 8:30 AM Room: 1015 McPHERSON LAB Chair: YUNJIE XU, University of Alberta, Edmonton, AB, Canada RD01 INVITED TALK 30 min 8:30 NITROGEN OXIDES, AEROSOLS AND OXYGENATED VOC: APPLICATIONS OF VISIBLE CAVITY ENHANCED OPTICAL EXTINCTION SPECTROSCOPY TO ATMOSPHERIC MEASUREMENTS STEVEN S. BROWN, NOAA Earth System Research Laboratory, Boulder, CO 80305. Cavity enhanced extinction spectroscopy, in which the long effective path lengths available within an optical cavity provide a highly sensitive measurement of optical extinction, has seen increasing application as an analytical method in atmospheric science in recent years. This presentation will survey recent developments of field instrumentation based on of cavity enhanced spectroscopy from our laboratories, with an emphasis both on the evolution of the technology and lessons learned from deployment on platforms such as tall towers, ships and aircraft. Examples include detection of nocturnal nitrogen oxides (NO , NO and N O ) by cavity ring-down spectroscopy, beginning with pulsed lasers but more recently with diode lasers; aerosol extinction spectroscopy; and measurements of -dicarbonyls using broadband methods. Although all of these examples are based on visible spectroscopy, they are illustrative of the variety of different light sources now in use, and they allow for some comparison between different approaches in terms of sensitivity and specificity. RD02 15 min 9:05 TRANSITION OF THE DETECTION OF THE MAGNETIC DIPOLE-ALLOWED ORIGIN BAND OF THE NITRATE RADICAL NO KANA TAKEMATSU, NATHAN EDDINGSAAS, and MITCHIO OKUMURA, Arthur Amos Noyes Laboratory of Chemical Physics, California Institute of Technology, Pasadena, California 91125; JOHN STANTON, Department of Chemistry, University of Texas at Austin, Austin, TX 78712. Despite its simplicity and atmospheric significance, the lowest electronic states of NO remain poorly understood. The E state is Jahn-Teller (JT) active and is pseudo-JT coupled to the ground A and excited E states. While transition is purely electric forbidden, the cavity ringdown spectrum of the vibronicallythe band origin 0 of the allowed bands has shown rotationally-resolvable structures. We have detected the magnetic dipole-allowed origin (7060 cm ) via CRD spectroscopy. Analysis of the band contour along with its implications of the JT/Pseudo-JT state of NO will be discussed. couplings in the dark 231 RD03 15 min 9:22 NO TRACE MEASUREMENTS BY OPTICAL-FEEDBACK CAVITY-ENHANCED ABSORPTION SPECTROSCOPY I. VENTRILLARD-COURTILLOT, Th. DESBOIS, T. FOLDES and D. ROMANINI, Laboratoire de Spectrométrie Physique, CNRS UMR5588, Univ. J. Fourier de Grenoble, St Martin d’H ères, France. In order to reach the sub-ppb NO detection level required for environmental applications in remote areas, we develop a spectrometer based on a technique introduced a few years ago, named Optical-Feedback Cavity-Enhanced Absorption Spectroscopy (OF-CEAS) [1]. It allows very sensitive and selective measurements, together with the realization of compact and robust set-ups as was subsequently demonstrated during measurements campaigns in harsh environments [2]. OFCEAS benefits from the optical feedback to efficiently inject a cw-laser in a V-shaped high finesse cavity (typically 10 000). Cavity-enhanced absorption spectra are acquired on a small spectral region (1 cm ) that enables selective and quantitative measurements at a fast acquisition rate with a detection limit of several 10 cm as reported in this work. Spectra are obtained with high spectral definition (150 MHz highly precisely spaced data points) and are self calibrated by cavity rind-down measurements regularly performed (typically every second). NO measurements are performed with a commercial extended cavity diode laser around 411 nm, spectral region where intense electronic transitions occur. We will describe the set-up developed for in-situ measurements allowing real time concentration measurements at typically 5 Hz; and then report on the measurements performed with calibrated NO reference samples to evaluate the linearity of the apparatus. The minimum detectable absorption loss is estimated by considering the standard deviation of the residual of one spectrum. We achieved 2x10 cm for a single spectrum recorded in less than 100 ms at 100 mbar. It leads to a potential detection limit of 3x10 molecules/cm , corresponding to about 150 pptv at this pressure. [1] J. Morville, S. Kassi, M. Chenevier, and D. Romanini, Appl. Phys. B, 80, 1027 (2005). [2] D. Romanini, M. Chenevrier, S. Kassi, M. Schmidt, C. Valant, M. Ramonet, J. Lopez, and H.-J. Jost, Appl. Phys. B, 83, 659 (2006). RD04 15 min 9:39 MEASUREMENTS OF PEROXY RADICALS USING CHEMICAL AMPLIFICATION/CAVITY RING-DOWN SPECTROSCOPY YINGDI LIU, Department of Chemistry, University of California, Riverside, CA 92521; RODRIGO MORALES-CUETO, Instituto de Quimica, Universidad Nacional Autonoma de Mexico, Ciudad Universitaria, 04510, Mexico, D.F., Mexico; JAMES HARGROVE, DAVID MEDINA, Department of Chemistry, University of California, Riverside, CA 92521; and JINGSONG ZHANG, Department of Chemistry and Air Pollution Research Center, University of California, Riverside, CA 92521. The peroxy radical chemical amplification (PERCA) method is combined with cavity ring-down spectroscopy (CRDS) to measure peroxy radicals HO and RO . HO and RO are converted to NO via reactions with NO, with subsequent reactions to recycle most of the OH and RO coproducts back to HO by reactions with CO and O and amplify the level of NO . The amplified NO is then monitored by CRDS, a sensitive absorption technique. The PERCA-CRDS method is calibrated with a HO radical source (0.5-3 ppb); using a 3-meter Teflon tubing as the reactor and 2.5 ppmv NO and 5% vol/vol CO, the PERCA amplification factor or chain length is determined to be 150 +-50 in this study. The peroxy radical detection sensitivity by PERCA-CRDS is approx. 5 pptv/30s. Ambient measurements of the peroxy radicals are carried out at Riverside, California in 2007 to demonstrate the PERCA-CRDS method. 232 RD05 15 min 9:56 QUANTITATIVE MEASUREMENTS OF ABSORPTION CROSS-SECTIONS BY DUAL WAVELENGTH CAVITY RING-DOWN SPECTROSCOPY RABI CHHANTYAL PUN, PHILLIP THOMAS, DMITRY G. MELNIK, and TERRY A. MILLER, Laser Spectroscopy Facility, Department of Chemistry, The Ohio State University, 120 W. 18th Avenue, Columbus, Ohio 43210. The organic peroxy radicals play an important role in atmospheric and combustion chemistry and their absolute concentrations provide key data for understanding these processes. These concetrations can be measured by monitoring the absorption by these species. To do this, however, the absorption cross-section must be known. Data on the cross-sections of peroxy transitions are abundant, but these transitions lack selectivity and their analytical use is limited. Restrong spectra of a number of peroxy radicals that are cently, we reported observation and analysis of selective, but weak quite selective. However, corresponding data on their absorption cross-section are scarse. Moreover, these cross-sections are hard to determine from even good quantum chemistry calculations.Cross-sections can be determined from observed fractional absorption if the concentration of the absorbing species is known. Determining concentrations of reactive intermediates is a challange which can be experimentally overcome by simultaneous observation of the absorption by the peroxy radical and by a co-product with well-known absorption properties (e.g., HCl). However, peroxy radicals and their co-product may absorb in very different frequency regions. To make such measurements we designed a dual wavelength CRDS system that allows probing the absorbing media along closely lying optical paths at different wavelengths at the same time. In this talk we will discuss the design of the novel apparatus and its capabilities and performance. As an example of an application, we present the measurement of the absolute absorption cross-section for the weakly absorbing transition of reactive intermediate, ethyl peroxy radical. Intermission RD06 CAVITY ATTENUATED PHASE SHIFT-BASED MONITORING OF ATMOSPHERIC SPECIES 10 min 10:30 P. L. KEBABIAN, T. B. ONASCH, S. C. HERNDON, E. C. WOOD, J. WORMHOUDT, and A. FREEDMAN, Aerodyne Research, Inc., Billerica, MA 01821. We are developing compact instruments for the monitoring of ambient atmospheric species, specifically nitrogen dioxide and particles, using cavity attenuated phase shift spectroscopy. The sensor, which detects the optical absorption of nitrogen dioxide within a 20 nm bandpass band centered at 440 nm, comprises a blue light emitting diode, an enclosed metal measurement cell (26 cm in length) incorporating a resonant optical cavity of near-confocal design and a vacuum photodiode detector. An analog heterodyne detection scheme is used to measure the phase shift in the waveform of the modulated light transmitted through the cell induced by the presence of nitrogen dioxide and/or particles within the cell. The entire apparatus is encased within a standard 19-inch rack-mounted enclosure. Levels of detection (1 s, 3 ! ) for nitrogen dioxide of 0.2 ppb and for aerosols of 3.5 Mm have been achieved. Examples of high resolution field measurements and comparisons with other instrumentation will be presented. 233 RD07 15 min 10:42 DETECTION OF IODINE MONOXIDE RADICALS IN THE MARINE BOUNDARY LAYER USING AN OPEN-PATH CAVITY RING-DOWN SPECTROMETER RYUICHI WADA, Solar-Terrestrial Environment Laboratory, Nagoya University, Nagoya, 464-8601, Japan; JOSEPH M. BEAMES, School of Chemistry, University of Bristol, Bristol, BS8 1TS, United Kingdom; and ANDREW J. ORR-EWING, School of Chemistry, University of Bristol, Bristol, BS8 1TS, United Kingdom. An open-path cavity ring down spectroscopy (CRDS) instrument for measurement of atmospheric iodine monoxide (IO) radicals has been tested in the laboratory and subsequently deployed in Roscoff as part of the Reactive Halogens in the Marine Boundary Layer (RHaMBLe) project in September 2006. In situ measurements are reported of local IO mixing ratios in the marine boundary layer. a The absorption cross section at the bandhead of the IO A - X (3,0) vibronic band was used to obtain the mixing ratios of atmospheric IO. The mixing ratios of IO were obtained on two days, peaked close to low tide, and were 5 - 10 times higher than values calculated from column densities previously reported by long-path, differential optical absorption spectroscopy (DOAS) in coastal regions. The typical detection limit of the instrument was estimated to be 10 pptv of IO with the total accumulation time of 30 s. The observations of relatively high concentration, compared to the values previously reported by DOAS, are consistent with the concurrent observations using a LIF (Laser induced Fluorescence) instrument. b The observed IO mixing ratios fluctuated, in part, because the open-path configurations had disadvantages that included perturbation of ring-down measurements by air currents and light scattering caused by aerosols. However these problems were more than amply compensated for by elimination of unknown sampling losses. The contribution of aerosol particles to the obtained IO mixing ratios will be discussed at the meeting. a R. b L. Wada, J. M. Beames and A. J. Orr-Ewing J. Atoms. Chem. 58, 69, 2007. K. Whalley, K. L. Furneaux, T. Gravestock, H. M. Atkinson, C. S. E. Bale, T. Ingham, W. J. Bloss and D. E. Heard J. Atoms. Chem. 58, 19, 2007. RD08 ROTATIONALLY RESOLVED ABSORPTION OF IN THE VISIBLE AT 90K 15 min 10:59 YASNAHIR PEREZ-DELGADO and CARLOS E. MANZANARES, Department of Chemistry and Biochemistry, Baylor University, Waco, Texas, 76798. The atmospheric red bands of molecular oxygen due to b magnetic dipole electronic transition have been obtained using the phase shift and pulsed cavity ring down technique. A low temperature cell was designed and adapted to the CRD experiment to measure absorption bands at any temperature between 10 K and 298 K using liquid He or liquid as cryogens. The spectra were obtained at room temperature and at 90 K. The rotationally resolved spectra of the (0,0) vibration band, A-band, at 762nm and the (2,0) vibration band, -band, at 628nm were obtained and compared with the simulated spectrum. This information was used to confirm the temperature of the cell. 234 RD09 CALCULATIONS AND FIRST QUANTITATIVE LABORATORY MEASUREMENTS OF O QUADRUPOLE LINE INTENSITIES AND POSITIONS 15 min 11:16 -BAND ELECTRIC DAVID A. LONG, MITCHIO OKUMURA, Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125, USA; CHARLES E. MILLER, HERBERT M. PICKETT, Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109, USA; DANIEL K. HAVEY, JOSEPH T. HODGES, Process Measurements Division, National Institute of Standards and Technology, 100 Bureau Drive, Gaithersburg, MD 20899, USA. Frequency-stabilized cavity ring-down spectroscopy (FS-CRDS) was utilized to make quantitative laboratory-based measurements of electric quadrupole transitions within the O A-band. We report the first observations of eight extremely weak (line intensities ranging from 3x to 2x cm molec.) transitions within the NO, PO, and RS branches. New theoretical calculations of line intensities and positions are also presented and compared to these measurements. 4 0.483 P Q(11) magnetic dipole line -9 -6 -1 [cτ] (10 cm ) -1 cm molec. 0.481 0.480 N -1 O(21) electric quadrupole line -30 -1 S = 3.74x10 cm molec. -1 12934.74895 cm 0.479 line -1 -27 S = 2.87x10 peak area (10 GHz cm ) b1 - X1 0.482 ∆N ∆J(N") N O(5) O(13) O(15) N O(17) N O(19) N O(21) N N 2 0.478 : Measured spectrum (symbols) and Voigt fit (line) of electric quadrupole line in the wings of the " +(11) hot band, magnetic dipole line. Peak signal-to-noise ratio on electric quadrupole line is 16:1. : Fit-derived peak areas vs. number density for the branch electric quadrupole lines. 0 0 2 4 detuning (GHz) 6 8 0 18 2x10 18 4x10 6x10 18 -3 number density (molec. cm ) RD10 15 min 11:33 EXPERIMENTAL LINE PARAMETERS OF HIGH-J TRANSITIONS IN THE O A-BAND USING FREQUENCYSTABILIZED CAVITY RING-DOWN SPECTROSCOPY DANIEL K. HAVEY, JOSEPH T. HODGES, Process Measurements Division, National Institute of Standards and Technology, 100 Bureau Drive, Gaithersburg, MD 20899, USA; DAVID A. LONG, MITCHIO OKUMURA, Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125, USA; CHARLES E. MILLER, Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109, USA. The reliability of high-J line parameters in spectroscopic databases can affect the uncertainty budget of experiments aiming to utilize optical probing to study highly rotationally excited molecules. Ultra-cold collision dynamics of O (E ), specifically, has recently been suggested as an intriguing but experimentally demanding system. One possibility would be to directly probe absorption transitions of O as it trickles down a ladder of rotational states via collisional relaxation following rotational excitation. In certain cases, another strategy might be to utilize optical absorption to probe the collision partner for O . Both of these experimental approaches require an understanding of the spectroscopy of elevated rotational states, and in particular the intensities and widths are important for quantifying molecular dynamics. In the case of rotationally excited species, these data would have to be obtained by extrapolation of line parameters from existing databases. Subtle deviations from the database line parameters, as revealed by experiments, may be amplified depending on how far in J the data are extrapolated. Our goals in this study are (I) to provide the highest-J spectroscopic measurements of line intensities and widths for the primary isotope of O in the A-band region and (II) to understand how the line parameters compare to, and build on, what is contained in the widely used HITRAN database. The experiments presented here are challenging because these lines are some of the weakest ever observed in the laboratory, thus requiring extremely sensitive optical detection methods. We have measured transitions between J’ = 32 and 50 (self-broadened) and J’ = 32 and 42 (air-broadened) and have demonstrated a minimum detectable line intensity of 2 10 cm molec. . Our highest J measurements probe lower states having rotational energies of 3775 cm , 40+ higher than the most extensive measurements to date. 235 RE. MINI-SYMPOSIUM: CONICAL INTERSECTIONS THURSDAY, JUNE 25, 2009 – 8:30 AM Room: 2015 McPHERSON LAB Chair: SCOTT REID, Marquette University, Milwaukee, Wisconsin RE01 INVITED TALK 30 min 8:30 FIRST PRINCIPLES DYNAMICS AROUND CONICAL INTERSECTIONS: THE ROLE OF THE ENVIRONMENT AND INTERSECTION TOPOGRAPHY TODD J. MARTINEZ, Department of Chemistry, Stanford University, Stanford, CA. We discuss some recent examples, drawn from small molecules and chromophores in solvated/protein environments, of excited state dynamics using the ab initio multiple spawning method. We explore the role of the environment in altering the energetics of conical intersections and/or their topography, e.g. sloped vs peaked. A first attempt at a rate theory incorporating these aspects will be presented and compared to dynamics results. A key question which we comment on is the number of degrees of freedom which should be required in such a rate model. Is a single reaction coordinate sufficient, or are conical intersection dynamics inextricably multi-dimensional? RE02 THREE-STATE CONICAL INTERSECTIONS IN BIOLOGICALLY RELEVANT MOLECULES 15 min 9:05 S. MATSIKA and K. A. KISTLER , Department of Chemistry, Temple University, Philadelphia, PA 19122. Three-state conical intersections, actual degeneracies between three electronic states that are not imposed by symmetry, have been shown in recent years to be present in many polyatomic molecules. These features may exist when there are at least five degrees of freedom present in the molecule. Their importance and effect on nonadiabatic dynamics, however, are not well understood. We have investigated the importance of two- and three-state conical intersections in photoinitiated processes of biologically relevant systems, and particularly the nucleic acid bases and their analogs. Three-state conical intersections have been located using multi-reference configuration-interaction ab initio methods. The potential energy surfaces for each base contain many different seams of three-state intersections. Paths along seams from these intersections are shown to be connected to well characterized stationary points involved in radiationless decay pathways. Nonadiabatic coupling terms have also been calculated, and the effects of the proximal third state on these quantities are detailed. In particular, it is shown that when one of these loops incorporates more than one seam point there is a profound and predictable effect on the phase of the nonadiabatic coupling terms, and as such provides a diagnostic for the presence and location of additional seams. RE03 15 min 9:22 PHOTO-REACTIVITY OF A PUSH-PULL MEROCYANINE IN A STATIC ELECTRIC FIELDS: A THREE STATE MODEL OF ISOMERIZATION REACTIONS INVOLVING CONICAL INTERSECTIONS S. ZILBERG, X. F. XU, A. KAHAN and Y. HAAS, Institute of Chemistry and the Farkas Center for Light Induced Processes The Hebrew University of Jerusalem, Jerusalem, Israel; ,. The photochemistry of a prototype push-pull merocyanine is discussed using a simple three state model. As a derivative of butadiene, two isomerization reactions may take place, around the two double bonds of the butadiene backbone. As a molecule substituted by an electron donor and electron acceptor at opposite ends, its structure as well as its photochemistry are expected to be strongly affected by the environment. It is shown that varying the solvent polarity or the electric field, can lead to different photochemical products. In particular, the existence of conical intersections is found to depend on these external parameters. This work provides a theoretical foundation for ideas expressed by Squillacote et al.* concerning the electrostatic control of photochemical reactions. *Squillacote, M.; Wang, J.; Chen, J. J. Am. Chem. Soc. 2004, 126, 1940. 236 RE04 15 min 9:39 SUBPICOSECOND EXCITED STATE LIFETIMES IN DNA POLYMERS REQUIRE UNSTACKED BASES KIMBERLY DE LA HARPE, CHARLENE SU, and BERN KOHLER, Department of Chemistry, The Ohio State University, Columbus, OH 43210. The femtosecond lifetimes of excited states of monomeric DNA bases are the result of nuclear motions that lead to one or more conical intersections (CIs). Surprisingly, femtosecond pump-probe experiments reveal that excitations in DNA base polymers, including ones with genomic or natural sequences of the four bases, decay at least an order of magnitude more slowly. Although the reasons for this dramatic change in photophysics are unclear, evidence strongly suggests that the long-lived states are exciplexes formed when an electron is partially transferred from one base to its $ -stacked neighbor. Experiments also show that monomer-like subpicosecond decay to the ground state is frequently observed in many DNA oligomers and polymers in addition to exciplex formation. We will present results from high-temperature and other experiments suggesting that monomer-like, CI-mediated dynamics are only possible when unstacked bases are present. RE05 DARK STATES IN SINGLE DNA BASES AND DNA BASE POLYMERS 15 min 9:56 BERN KOHLER, PATRICK M. HAREa , and CHRIS T. MIDDLETON b, Department of Chemistry, The Ohio State University, Columbus, OH 43210. DNA is vulnerable to photochemical modification by UV light. The excited electronic states that initiate DNA damage have been difficult to characterize due to their ultrashort lifetimes, and most excitations in single DNA bases decay to the electronic ground state in hundreds of femtoseconds. Although many workers have now located conical intersections between various electronic states of the nucleobases, there is still confusion over the precise dynamics that lead to deactivation. This is especially true for the pyrimidine bases where the initial Franck-Condon population bifurcates with some molecules decaying to the ground state and others relaxing to a relatively long-lived n$ * state. Results from UV/UV and UV/mid-IR transient absorption experiments will be presented that illustrate these dual decay pathways. Evidence suggests that the n$ * state mediates intersystem crossing to the triplet state. Finally, current understanding of how these single-base decay pathways are modified by interactions in DNA polymers will be discussed. a Current b Current address: Department of Chemistry, Northern Kentucky University, Highland Heights, KY 41099 address: Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706 Intermission 237 RE06 15 min 10:30 NON-RADIATIVE RELAXATION OF ELECTRONICALLY EXCITED DNA OLIGOMERS: PROTON COUPLED CHARGE TRANSFER ADRIAN W. LANGE and JOHN M. HERBERT, Ohio State University Department of Chemistry, Columbus, OH. We address possible relaxation mechanisms of electronically excited DNA oligomers with a combined quantum mechanics/molecular mechanics (QM/MM) approach. Using long-range corrected density functional theory (LRC-DFT), we show that charge transfer (CT) states between neighboring nucleobases appear at energies just above optically bright $$ excitonic states in aqueous solution. In double stranded DNA systems, both intrastrand and interstrand CT states are observed. It has been hypothesized that excitonic states may decay via a conical intersection into a CT state on a subpicosecond timescale. The proximity in energy of such states in out calculations appears consistent with this claim. Assuming that such a non-radiative mechanism occurs, we investigate subsequent relaxation of CT states by constructing and optimizing the geometry of model CT systems with constrained density functional theory (CDFT) a . We find that CT states relax in double stranded DNA through proton transfer across Watson-Crick base pairs with little to no energy barrier. Furthermore, the ground state energy shifts upwards along this reaction coordinate to nearly the same as that of the proton coupled charge transfer state, creating the possibility for a non-radiative pathway to the ground state. a Q. Wu and T. Van Voorhis Phys. Rev. A (2005) RE07 EXCITED STATES OF NON-ISOLATED CHROMOPHORES 15 min 10:47 S. MATSIKA and C. KOZAK and K. KISTLER, Department of Chemistry, Temple University, Philadelphia, PA 19122. The photophysical and photochemical behavior of nucleobases is very important because of their biological role as the building blocks in DNA and RNA. Great progress has been made in understanding the excited-state properties of single bases. In order to understand the photophysical properties of nucleobases in complex environments we have investigated their excited states (a) in aqueous solutions and (b) as $ -stacked dimers in DNA. The solvatochromic shifts of the excited states of pyrimidine nucleobases in aqueous solution have been investigated using a combined QM/MM procedure where the quantum mechanical solute is described using high level multireference configuration interaction methods while molecular dynamics simulations are used to obtain the structure of the solvent around the solute in an average way. The excited states of $ -stacked nucleobases have also been investigated using various ab initio methods. The effect of the environment on the excited states and conical intersections is investigated. 238 RE08 HOONO ISOMERIZATION TO HONO INVOLVING CONICAL INTERSECTIONS 10 min 11:04 T. J. DHILIP KUMAR, Department of Atmospheric, Oceanic and Space Sciences, University of Michigan, Ann Arbor, MI 48105; JOHN F. STANTON, Institute for Theoretical Chemistry, Department of Chemistry and Biochemistry, University of Texas at Austin, Austin, TX 78712; and JOHN R. BARKER, Department of Atmospheric, Oceanic and Space Sciences, University of Michigan, Ann Arbor, MI 48105. The important atmospheric reactions HO + NO and OH + NO lead to formation and dissociation of the cis- and transisomers of the HOONO complex. In the present work, the global HNO potential energy surface (PES) is being studied by using high-level ab initio electronic structure methods. This PES a and others in the same class have been studied previously by others. In the F + NO reaction system, UCCSD(T) calculations showed that FONO isomerizes to FNO through a tight transition state involving a two-state avoided curve crossing b . A similar mechanism has been invoked for HOONO, which is isoelectronic with FONO. CASSCF multi-configurational calculations on the CH O + NO reaction located a conical intersection near where single-configurational DFT methods predict an intrinsic energy barrier; the barrier was suggested to be an artifactc . In present work, the global HNO PES is being investigated by both the UCCSD(T) and CASSCF methods in order to study the influence of low-lying excited electronic states on the ground state PES and reaction dynamics. a L. P. Olsen, M. D. Bartberger and K. N. Houk, J. Am. Chem. Soc., 125, 3999 (2003). B. Ellison, J. M. Herbert, A. B. McCoy, J. F. Stanton and P. G. Szalay, J. Phys. Chem. A 108, 7639 (2004). c J. F. Arenas, F. J. Avila, J. C. Otero, D. Pel ez and J. Soto, J. Phys. Chem. A 112, 249 (2008). b G. RE09 15 min 11:16 H-ATOM ELIMINATION CHANNEL IN UV PHOTODISSOCIATION OF N-PROPYL AND ISO-PROPYL RADICALS: THE ROLE OF CONICAL INTERSECTIONS XIANFENG ZHENG, WEIDONG ZHOU, YU SONG, Department of Chemistry, University of California, Riverside, CA 92521; and JINGSONG ZHANG, Department of Chemistry and Air Pollution Research Center, University of California, Riverside, CA 92521. The H-atom elimination channels in the UV photodissociation of jet-cooled n-propyl and iso-propyl radicals are studied in the region of 237 nm using the high-n Rydberg-atom time-of-flight technique. Upon excitation to the 3p state by the UV photolysis radiation, n-propyl radical and iso-propyl radical dissociate into the H atom and propene products. The product center-of-mass translational energy release of both n-propyl and iso-propyl radicals have bimodal distributions. The H-atom product angular distribution in n-propyl is anisotropic (with beta ˜ 0.5), and that in iso-propyl is isotropic. The overall average translational energy release is E ˜ 0.27E! for n-propyl and E ˜ 0.21E! for iso-propyl. The bimodal translational energy distributions indicate two dissociation pathways: (i) a unimolecular dissociation pathway from the ground-state propyl after internal conversion from the 3p state, and (ii) a repulsive pathway directly connected with the excited state of the propyl radical. Isotope labeling experiments have also been carried out. The possible photodissociation mechanisms and the role of conical intersections will be discussed. 239 RE10 10 min 11:33 CONFORMER SELECTIVE AND VIBRATIONALLY MEDIATED PHOTODISSOCIATION STUDY OF PROPANAL CATION LEI SHEN, MYUNG HWA KIM, BAILIN ZHANG, ARTHUR G. SUITS, Department of Chemistry, Wayne State University, Detroit, MI, 48202. We report the conformationally and vibrationally selected imaging study of propanal obtained by resonance-enhanced multiphoton ionization (REMPI). The photoelectron spectra, employing the (2+1) ionization via the (n, 3s) Rydberg transitions in the range from 365 to 371 nm, confirm that there are two stable conformer origins in the lowest ionic state, the cis conformer with a co-planar CCCO geometry and a gauche conformer with a 119 CCCO dihedral angle. We also study the photodissociation dynamics of propanal cation initially prepared in some certain vibrational modes or conformation. The product kinetic energy distributions for the H elimination channels are bimodal, and the two peaks are readily assigned to propanal cation + H and hydroxyallyl cation + H. The ratio of the fast product with respect to the whole product is varied according to different vibrational mode preparation. However, cis form appears the lowest and gauche form yield the highest ratio. Full multiple spawning dynamical calculations show that distinct ultrafast dynamics in the excited state leads to internal conversion to the ground state in isolated regions of the potential surface for the two conformers, and from these distinct regions, conformer interconversion does not effectively compete with dissociation. 240 RF. ELECTRONIC THURSDAY, JUNE 25, 2009 – 1:30 PM Room: 160 MATH ANNEX Chair: ANTHONY MERER, Academia Sinica, Taipei, Taiwan RF01 10 min 1:30 INTRACAVITY LASER ABSORPTION SPECTROSCOPY OF PLATINUM FLUORIDE IN THE NEAR INFRARED LEAH C. O’BRIEN, RACHEL A. HARRIS, Department of Chemistry, Southern Illinois University, Edwardsville, IL 62026-1652; JAMES J. O’BRIEN, Department of Chemistry, University of Missouri, St Louis, MO 63121-4499. A new electronic transition of PtF has been recorded using intracavity laser absorption spectroscopy. This is the first reported spectroscopic observation of PtF. The results of the analysis will be presented. The gas phase PtF molecules were produced using a platinum-lined hollow cathode in an argon-based electric discharge with a small amount of SF . RF02 10 min 1:42 INTRACAVITY LASER ABSORPTION SPECTROSCOPY OF NICKEL FLUORIDE IN THE NEAR INFRARED JAMES J. O’BRIEN, Department of Chemistry, University of Missouri, St Louis, MO 63121-4499; LEAH C. O’BRIEN, RACHEL A. HARRIS, Department of Chemistry, Southern Illinois University, Edwardsville, IL 62026-1652. The (1,0) band of the [11.1] - X transition of NiF has been recorded using intracavity laser absorption spectroscopy. The analysis was straight-forward and based on the known - values determined from microwave spectroscopy. Results of the analysis will be presented. The gas phase NiF molecules were produced using a nickel-lined hollow cathode in an argon-based electric discharge with a small amount of SF . RF03 15 min 1:54 HIGH RESOLUTION LASER SPECTROSCOPY OF IRIDIUM MONOFLUORIDE AND IRIDIUM MONOCHLORIDE A. G. ADAM, L. E. DOWNIE, S. J. FORAN, and A. D. GRANGER, Chemistry Department, and Centre for Lasers, and Atomic, and Molecular Sciences, University of New Brunswick, Fredericton, NB, E3B 5A3; and D. FORTHOMME, C. LINTON, and D. W. TOKARYK, Physics Department, and Centre for Lasers, and Atomic, and Molecular Sciences, University of New Brunswick, Fredericton, NB, E3B 5A3. High resolution laser spectra of IrF and IrCl have been acquired in the visible region of the spectrum. The molecules were produced by laser ablation of an iridium target rod followed by reaction with 1% SF or CHCl seeded in He in a pulsed supersonic jet. The characterization and preliminary analysis of two electronic transitions of IrF, A - X and B - X , observed by laser-induced fluorescence between 450 nm and 665 nm, were reported at this conference last year (paper MF11). However, the 3-0 band of the A-X system was perturbed and we present the results of the deperturbation and the final analysis here. New spectra of the IrCl molecule have been taken. A strong transition with an upper state vibrational progression between 530 to 575 nm has been observed. Dispersed fluorescence from the bands gives a ground state vibrational interval of approximately 413 cm . Molecular constants for the excited and ground states which, like IrF, are consistent with a - X assignment, will be presented. 241 RF04 15 min 2:11 ANALYSIS OF THE MAGNETIC HYPERFINE STRUCTURE IN THE MONOFLUORIDE, IrF BAND SYSTEM OF IRIDIUM HAILING WANG, XIUJUAN ZHUANG AND TIMOTHY C. STEIMLE , Department of Chemistry and Biochemistry, Arizona State University, Tempe,AZ 85287; COLAN LINTON, Center for Lasers, Atomic and Molecular Sciences and Physics Department, University of New Brunswick, Fredericton, NB Canada E3B 5A3. Recently the New Brunswick group a reported on the detection and analysis of the band system of IrF. The free-jet expansion conditions limited the spectral resolution to approximately 200 MHz, which was insufficient to fully resolve the Ir(I=3/2), Ir(I=3/2)and F(I=1/2)magnetic hyperfine splitting. Here we report on the analysis of the same band system recorded under molecular beam conditions which resulted in a resolution of 40 MHz. A simple molecular orbital correlation diagram is used to rationalize the determined parameters of IrF and the isovalent molecules RhF b and CoFc . a A.G. Adam; A.D. Granger; L.E. Downie; D.W. Tokaryk and C. Linton Can.J. Phys. (accepted). Li, R.J. Jensen, W.J. Balfour, S.A. Shepard and A.G. Adam; J.Chem.Phys. 121 2591, 2004. c J.J. Harrison, J.M. Brown, M.A. Flory, P.M. Sheridan, S.K. McLamarrah and L.M. Ziurys J. Chem. Phys. 127 194308, 2007. b R. RF05 LASER INDUCED FLUORESCENCE SPECTRUM OF IRIDIUM MONOPHOSPHIDE 10 min 2:28 H.F. PANG, ANWEN LIU AND A. S-C. CHEUNG, Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong.. Laser induced fluorescence spectrum of IrP in the spectral region between 380-600 nm has been studied. Reacting laser ablated iridium atoms with 1% PH seeded in argon produced the IrP molecule. A few vibronic transitions have been recorded. Preliminary analysis of the rotational structure indicated that these vibronic bands are with , = 0 and , = 0 and is likely to be - X transition. Vibrational separation of the excited state is estimated to be about 442 cm . ˚ . This work represents the first experimental investigation of the The ground state bond length is determined to be 1.766 spectra of IrP. RF06 15 min 2:40 LASER SPECTROSCOPY OF NiI: NEW ELECTRONIC STATES AND HYPERFINE STRUCTURE A. S-C. CHEUNG, H.F. PANG, W.S. TAM, J. YE, AND J. W-H. LEUNG, Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong.. Two new electronic transition systems of NiI namely: the [14.0] - X and the [15.7] - X transitions were observed and analyzed using laser vaporization/reaction supersonic free jet expansion and high resolution laser induced fluorescence spectroscopy. In addition, the (v, 0) bands with v = 6 - 10 of the previously identified [14.6] - X transition were found to be perturbed by the [15.7] state. All observed spectra show partially resolved hyperfine structure. Hyperfine width of rotational lines decreases rapidly as J increases suggested that the hyperfine structure for the [14.0] , the [14.6] and the [15.7] states conform to the Hund’s case a coupling scheme. The interaction between the [14.6] and the [15.7] states is evident in the progressive increase in hyperfine width in rotational lines of the [14.6] - X transition as the vibrational quantum number increases. Deperturbation procedures were successfully applied to analyze the interaction between these two states. Accurate molecular and hyperfine constants for the [14.0] , the [14.6] and the [15.7] states were obtained and interpreted. Intermission 242 RF07 X-RAY SPECTROSCOPY OF GOLD NANOPARTICLES 15 min 3:15 SULTANA N. NAHAR, M. MONTENEGRO, A.K. PRADHAN, Department of Astronomy, The Ohio State University, Columbus, OH 43210; R. PITZER, Department of Chemistry, The Ohio State University, Columbus, OH 43210. Inner shell transitions, such as 1s-2p, in heavy elements can absorb or produce hard X-rays, and hence are widely used in nanoparticles. Bio-medical research for cancer treatment has been using heavy element nanoparticles, embeded in malignant tumor, for efficient absorption of irradiated X-rays and leading emission of hard X-rays and energetic electrons to kill the surrounding cells. Ejection of a 1s electron during ionization of the element by absorption of a X-ray photon initiates the Auger cascades of emission of photons and electrons. We have investigated gold nanoparticles for the optimal energy range, below the K-edge (1s) ionization threshold, that corresponds to resonant absorption of X-rays with large attenuation coefficients, orders of magnitude higher over the background as well as to that at K-edge threshold. We applied these attenuation coefficients in Monte Carlo simulation to study the intensities of emission of photons and electrons by Auger cascades. The numerical experiments were carried out in a phantom of water cube with a thin layer, 0.1mm/g, of gold nanoparticles 10 cm inside from the surface using the well-known code Geant4. We will present results on photon and electron emission spectra from passing monochromatic X-ray beams at 67 keV, which is the resonant energy for resonant K lines, at 82 keV, the K-shell ionization threshold, and at 2 MeV where the resonant effect is non-existent. Our findings show a high peak in the gold nanoparticle absorption curve indicating complete absorption of radiation within the gold layer. The photon and electron emission spectra show resonant features. ab a Acknowledgement: Partially supported by a Large Interdisciplinary Grant award of the Ohio State University and NASA APRA program (SNN). The computational work was carried out on the Cray X1 and Itanium 4 cluster at the Ohio Supercomputer Center, Columbus Ohio. b ”Resonant X-ray Irradiation of High-Z Nanoparticles For Cancer Theranostics” (refereed presentation), A Pradhan, S Nahar, M Montenegro, C Sur, M Mrozik, R Pitzer, E Silver, Y Yu, 50th Annual Meeting of the American Association of Physicists in Medicine in Houston, Texas, July 27 - 31, 2008 RF08 10 min 3:32 INTRACAVITY LASER ABSORPTION SPECTROSCOPY OF PLATINUM NITRIDE IN THE NEAR INFRARED LEAH C. O’BRIEN, RACHEL A. HARRIS, Department of Chemistry, Southern Illinois University, Edwardsville, IL 62026-1652; SEAN WHITTEMORE, JAMES J. O’BRIEN, Department of Chemistry, University of Missouri, St Louis, MO 63121-4499. A new electronic transition of PtN has been recorded using intracavity laser absorption spectroscopy. Four red-degraded branches are observed, with a bandheads located at 11733 and 11725 . The results of the analysis will be presented and compared with ab initio calculations. 243 RF09 15 min 3:44 MAGNETIC g -FACTORS AND ELECTRIC DIPOLE MOMENTS OF LANTHANIDE MONOXIDES: PrO HAILING WANG,TIMOTHY C. STEIMLE, Department of Chemistry and Biochemistry, Arizona State University, Tempe,AZ 85287; COLAN LINTON, Physics Department, University of New Brunswick, Fredericton, NB Canada E3B 5A3. The very complex optical spectra of the lanthanide monoxides are caused by the insensitivity of the electronic energies to the numerous possible arrangements of the Ln electrons in the 4f and 6s orbitals. Disentangling the complex optical spectra may be aided by using simple Ligand Field Theory(LFT) to establish the global electronic structure for the lowlying electronic states. A comparison of experimentally determined permanent electric dipole moments, ! , and magnetic dipole moments, , is an effective means of sorting this myriad of states and assessing the quality of LFT and other electronic structure methodologies. Here we report on the determination of the permanent electric dipole moments, ! , and magnetic g -factors for the X (, = 4.5) and [18.1] (, = 5.5) states of PrO from the analysis of the optical Stark and Zeeman spectra. The g -factors are compared with those computed using wavefunctions predicted from ligand field theorya. The ! value for the X (, = 4.5) state is compared to ab initio b , and density functional c predictions and with the experimental values of other lanthanide monoxides. A phenomenological fit of ! for the entire series of LnO is used to predict ! for the isovalent actinide monoxide series. a Carette, P.,; Hocquet,A.J. Mol. Spectrosc.131 301, 1988. M.; Stoll, H. Theor. Chim. Acta. 75,369, 1989. c Wu, Z.; Guan, W. Meng, J. Su, Z. J. Cluster Science 18 444, 2007. b Dolg, RF10 THE 10 min 4:01 - BAND SYSTEM OF SrF REVISITED TIMOTHY C. STEIMLE , ANH LE, Department of Chemistry and Biochemistry, Arizona State University, Tempe,AZ 85287. Recently DeMille et ala proposed using SrF and other heavy diatomic molecules to measure nuclear spin-dependent parity violation (NSD-PV). In this scheme the =0 (+-parity) levels of the (v=0) state will be magnetically tuned into near degeneracy with the =1(- parity) levels. The pairs of nearly degenerate levels are mixed by NSD-PV interactions. The process will be monitored using the optical - transition. Here we report on the analysis of the (1,0) band for SrF and the (0,0) band for SrF of the - system recorded at near natural linewidth limit. A combined fit of the optical spectra with the previously recorded rf-transitions b and pure rotational transitions c was performed. a D. DeMille, S.B. Cahn, D. Murphree, D.A. Rahmlow and M.G. Kozlov, Phys. Rev. Lett. 100 023003, 2008. Azuma, W. J. Childs and G. L. Goodman, T. C. Steimle, J. Chem. Phys. 93 1990 93, 5533. c H.-U. Schltz-Pahlmann, Ch. Ryzlewicz, J. Hoeft,and T. Trring, 93,74 (1982)Chem. Phys. Lett. 93 74, 1982. b Y. 244 RF11 POPULATION DEPLETION SPECTROSCOPY OF STRONTIUM MONOMETHOXIDE 15 min 4:13 D. FORTHOMME , L. E. DOWNIE, A. D. GRANGER, A. G. ADAM, C. LINTON, D. TOKARYK, Centre for Laser, Atomic and Molecular Sciences, Physics and Chemistry Departments, University of New Brunswick, Fredericton, NB, Canada, E3B 5A3; W. S. HOPKINS , Physical and Theoretical Chemistry Laboratory, Department of Chemistry, University of Oxford, Oxford, U.K. OX1 3QZ. High resolution laser induced fluorescence excitation spectra have been obtained of the origin bands of the A E X A and B A X A transitions for two isotopologues, SrO CH and SrO CH , of strontium monomethoxide. The molecules were produced by laser ablation of a strontium target rod followed by reaction with C - or C - substituted methanol seeded in helium, prior to expansion into vacuum to form a pulsed supersonic jet. The spectra were complex and more congested than those we previously reported for the isoelectronic calcium monomethoxide molecule. Rotational J assignments were established from common ground state combination differences. Definitive assignments of the K structure and of the F F spin rotation components of the B A state were, however, much harder to establish and could only be achieved using optical optical double resonance (OODR) population depletion spectroscopy. We will report the latest results and analysis and also show how, by employing OODR, we were able to resolve and quantify the very small spin rotation splitting in the ground X A state. RF12 15 min 4:30 LASER SPECTROSCOPY OF BaOH AND BaOD: ANOMALOUS SPIN-ORBIT COUPLING IN THE STATE J. D. TANDY, J.-G. WANG, and P. F. BERNATH, Department of Chemistry, University of York, Heslington, York, YO10 5DD, UK. transition of BaOD has been rotationally analyzed using high-resolution laser excitation spectroscopy. The BaOD molecules were synthesized in a Broida-type oven and detected using a single mode Ti:Sapphire laser. Measured rotational lines have been assigned, and rotational and fine structure parameters determined through a combined least state. A significantly different spin-orbit coupling squares fit with the millimeter-wave pure rotational data of the constant from the corresponding value for BaOH was observed and attributed to global and local perturbations arising from vibrationally excited bands of the state. --doubling constants for the state also showed poor agreement with , the predictions of the pure precession model. To further understand the nature of the interactions between the and states of BaOH, a V-type optical-optical double resonance spectroscopy experiment was prepared to locate the lower-lying excited state levels. Preliminary results have yielded a band in close proximity on the lower wavenumber side of the spin component of BaOH with a relatively large value. Further results of this ongoing experiment will be presented. RF13 THE OPTICAL STARK SPECTRA OF CoF AND CoH 15 min 4:47 HAILING WANG, XIUJUAN ZHUANG, AND TIMOTHY C. STEIMLE , Department of Chemistry and Biochemistry, Arizona State University, Tempe,AZ 85287. Comparing the predicted and observed permanent electric dipole moments, ! , for simple diatomic cobalt containing molecules is a means of testing computational methodologies used for modeling cobalt-catalyzed reactions. Here we report on the experimental determination of ! for CoH and CoF from the analysis of the Stark shifts in the (0,0) bands of the system of cobalt monohydride, CoH, and the &%' system of cobalt monofluoride, CoF. In addition, the proton magnetic hyperfine interaction in CoH is analyzed. The relative values for ! are rationalized using a molecular orbital correlation diagram and with high-level ab initio predictions a. a Tomonari,M.; Okuda, R.; Nagashima, U.; Tanaka, K.; Hirano, T.;J. Chem. Phys. 126 144307, 2007. 245 RF14 15 min 5:04 A NEGATIVE ION PHOTOELECTRON SPECTROSCOPIC AND COMPUTATIONAL STUDY OF Mo AND Mo BEAU J. BARKER, SUNIL BAIDAR, SEAN M. CASEY and DOREEN G. LEOPOLD, Department of Chemistry, University of Minnesota, Minneapolis, MN 55455. We report the 488 and 514 nm anion photoelectron spectra of Mo . Neutral Mo has been described in recent * 9 99 studies as having a bond order of six, predicted to be the highest of any homonuclear diatomic, exceeding even that of Cr (five). The photoelectron spectrum of Mo confirms the previously measured vibrational frequency of gas phase Mo and displays transitions to vibrational levels up to v=7 in its ground state. The electron affinity of Mo is measured to be 0.732 0.010 eV. The Mo ground state is assigned as a state, in which the extra electron occupies a formally antibonding ! orbital of primarily 5 atomic parentage. A Franck-Condon analysis of the vibrational band intensities indicates a change in the equilibrium bond length of only 0.03 0.02 Å upon electron detachment. These results, and the similar vibrational frequencies measured for Mo and Mo , suggest that the anion HOMO is essentially nonbonding. Weak photodetachment transitions to excited states of Mo lying within 1.2 eV of its ground state are also observed. DFT calculations using the BPW91/SDD method show good agreement with experiment for the electron affinity of Mo and the bond lengths in the anion and neutral molecule ground states. It is hoped that these spectroscopic results will motivate and assist high level theoretical studies of the Mo anion. RF15 15 min 5:21 PHOTODISSOCIATION SPECTROSCOPY AND DISSOCIATION DYNAMICS OF TiO (CO ) MANORI PERERA RICARDO B. METZ , Department of Chemistry, University of Massachusetts Amherst , Amherst, MA. TiO (CO ) is produced by reaction of laser-ablated titianium atoms with CO and subsequent clustering, supersonically cooled and its electronic spectroscopy characterized by photofragment spectroscopy, monitoring loss of CO . The photodissociation spectrum consists of a vibrationally-resolved band in the visible, with extensive progressions in the covalent Ti-O stretch (952 cm vibrational frequency and 5 cm anharmonicity), and in the TiO -(CO ) stretch (186 cm ) and rock (45 cm ). The band origin is at 13918 cm , assigned using titanium isotope shifts, and the spectrum extends to 17350 cm . The excited state lifetime decreases dramatically with increasing internal energy, from 1100 ns for the lowest energy band (v " # =0), to 550 ns for v " # =3. The long photodissociation lifetime substantially reduces the photodissociation quantum yield at low energy, likely due to competition with fluorescence. Electronic structure calculations help to assign the spectrum of TiO (CO ) and predict allowed electronic transitions of TiO in the visible, which have not been previously measured. Time-dependent density functional calculations predict that the observed transition is due to B, X, in the TiO chromophore, and that binding to CO red shifts the TiO transition by 1508 cm , and lowers the Ti-O stretch frequency by 16 cm . Combining the computational and experimental results, the state of TiO is predicted to lie at T cm , with frequency 7 e = 968 cm and anharmonicity 7 exe = 5 cm . The calculations also predict that there is only one low-lying state of TiO , contrary to conclusions derived from photoelectron spectroscopy of TiO. Prospects for astronomical observation of TiO via the - transition are also discussed. a a Department of Chemistry, University of Illinois at Urbana-Champaign 246 RG. ASTRONOMICAL SPECIES AND PROCESSES THURSDAY, JUNE 25, 2009 – 1:30 PM Room: 170 MATH ANNEX Chair: DeWAYNE HALFEN, University of Arizona, Tucson, Arizona RG01 15 min 1:30 HIGH-SENSITIVITY, BROADBAND SPECTRAL LINE SURVEYS OF STAR FORMING REGIONS WITH THE CSO SUSANNA L. WIDICUS WEAVER, Department of Chemistry, Emory University, Atlanta, GA 30322; MATTHEW C. SUMNER, FRANK RICE, JONAS ZMUIDZINAS, Division of Physics, Mathematics, and Astronomy, California Institute of Technology, Pasadena, CA 91125; GEOFFREY A. BLAKE, Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125. Spectral line surveys are powerful tools for astrochemistry because they circumvent the one-line-at-a-time approach that has historically hampered new molecule identification. Until recently, line surveys were typically motivated by the need to characterize the major components of interstellar clouds, i.e. the so-called “interstellar weeds.” Previously reported surveys therefore often do not provide the sensitivity levels required for identification of new molecules with weak spectral signatures. The goal of our recent observations with the Caltech Submillimeter Observatory (CSO) is to shift the focus of spectral line surveys away from the interstellar weeds and toward detection of new interstellar molecules. We have obtained broadband, high-sensitivity spectra toward several star forming regions with the new 4=1 mm receiver at the CSO. When used with the facility AOS’s, this receiver affords 4 GHz of DSB spectral coverage for each LO setting. We have employed a stepped frequency-offset approach to allow for full spectral deconvolution. The noise temperature of this receiver is 100 K (SSB), resulting in spectral RMS levels that far surpass those reported in similar previous studies. Our initial observations targeted the Orion and Sagittarius B2(N-LMH) hot cores and a collection of Class 0 sources. We have now completed our coverage of these initial targets, and upcoming observing time has been allocated for similar surveys of the hot cores W51 e1/e2 and G34.3+0.2. We have fully deconvolved 28 GHz of spectra on Orion with RMS levels of T $ 20 mK. Our coverage on Sgr was more limited, yielding 8 GHz of fully-deconvolved spectra to the same RMS level. In this talk, we will report on the data analysis for the Orion and Sgr observations, discuss our progress on line surveys of other star-forming regions, and discuss the implications of these results in the context of recent hot core astrochemical models. RG02 CURRENT RESULTS FROM A SPECTRAL-LINE SURVEY OF SGR B2(N) 15 min 1:47 D. T. HALFEN and L. M. ZIURYS, Department of Chemistry, Department of Astronomy, and Steward Observatory, University of Arizona, Tucson, AZ 85721. One of the most chemically-rich giant molecular clouds is Sgr B2(N), which is located near the Galactic center. Using the Arizona Radio Observatory (ARO) telescopes, the Kitt Peak 12m and the Submillimeter Telescope (SMT), a spectral-line survey of this object at the confusion limit is being conducted across the entire 1, 2, and 3mm atmospheric windows from 65-280 GHz. The 3 and 1mm data are being collected with ALMA-type sideband separating mixers with unprecedented sensitivity and stability, as well as excellent image rejection. Typical noise levels achieved are 9-15 mK peak-to-peak. This survey is currently 70% complete. The current data show that several potential prebiotic species, such as acetamide and methyl amine, are present in this source, while others are not. These results indicate that interstellar chemistry follows specific pathways that selectively lead to certain compounds. A preliminary comparison of the currently detected species in Sgr B2(N) to the compounds found in meteorites will also be presented. 247 RG03 15 min 2:04 HCO IN THE HELIX NEBULA L. N. ZACK and L. M. ZIURYS, Department of Chemistry, Department of Astronomy, and Steward Observatory, University of Arizona, Tucson, AZ, 85721. The J = 10 transition of HCO is currently being mapped across the planetary nebula NGC7293, the Helix Nebula, using the Arizona Radio Observatory (ARO) 12m telescope. The spatial resolution at 89 GHz, the J = 10 transition frequency, is 70 arcsec and the map will encompass the region 1000 arcsec 800 arcsec with spacings of 35 arcsec. Approximately 10% of the map has been completed, and the data already indicate that HCO emission is widespread across the Helix Nebula and has a complex kinematic structure that often differs from that of CO. The extended distribution of HCO also suggests that dense clumps may exist throughout the nebula. The chemistry of old planetary nebulae may be more active than previously thought. RG04 THE GBT PRIMOS PROJECT - SCIENCE, STATUS, AND SUSPICIONS 15 min 2:21 ANTHONY J. REMIJAN, National Radio Astronomy Observatory, 520 Edgemont Road, Charlottesville, VA 22903; J. M. HOLLIS, NASA’s Goddard Space Flight Center, Computational and Information Sciences and Technology Office, Greenbelt, MD, 20771; P. R. JEWELL, National Radio Astronomy Observatory, 520 Edgemont Road, Charlottesville, VA 22903; F. J. LOVAS, NIST, Optical Technology Division, 100 Bureau Drive, Gaithersburg, MD 20899. In the Fall of 2007 we began observations to conduct a GBT legacy spectroscopic survey of SgrB2(N-LMH) in order to provide a complete inventory of known and unidentified species in the range of 300 MHz to 50 GHz. This survey will be the deepest spectral line survey to date toward this source at these frequencies and the data are being provided to the astronomical community on a quarterly basis (as available) as data accumulate in order to facilitate the identification of new interstellar species and deduce likely molecular formation chemistry. To date, we have completed 45 sessions toward Sgr B2N. This corresponds to 245 hours completed out of 625 approved which is 39% of the project. Over 720 individual spectral line features have been detected with 240 of the 720 being unidentified. In this presentation are summarized the science, current status of the observations and the suspicious transitions detected that may be from new molecular species. In addition, also addressed is the probability of the unambiguous identification of new molecules at these frequencies with exceeding low spectral line density. As has been the case for the last 2 years, researchers can obtain and analyze the raw or fully calibrated spectral line data available at: http://www.cv.nrao.edu/ aremijan/PRIMOS/. 248 RG05 15 min 2:38 SEARCH FOR HOT AND BRIGHT STARS FOR H SPECTROSCOPY NEAR THE GALACTIC CENTER TAKESHI OKA, Department of Astronomy and Astrophysics and Department of Chemistry, University of Chicago, Chicago, IL 60637; T. R. GEBALLE, Gemini Observatory, Hilo, HI 96720. It is becoming increasingly clear that H is abnormally abundant near the Galactic center and that it is a powerful probe for studying the gas in that region. To date we have observed a dozen sightlines toward bright and hot stars close to the Galactic plane (within 3 pc) and located in the region from the center to 30 pc east of the center. They are mostly stars belonging to the super-massive Quintuplet Cluster and the Central Cluster, but also include few lying between the two cm demonstrating the ubiquity of clusters. All sightlines showed H with column densities on the order of 4 10 a H , its high volume filling factor, and high ionization rate of H in the region. We plan to expand the region in which we have probed for H by two orders of magnitude in solid angle by covering the whole of the Central Molecular Zone (CMZ), the region with a radius of 200 pc from the center. For this purpose, the first requirement is to find bright and hot stars suitable for the H spectroscopy in this more extended region, in which few if any such stars are known outside of the clusters. We are using the recent GLIMPSE Point Source Catalogue provided by the Spitzer Space Telescope together with 2MASS photometry to identify such stars. Out of the over one million stars in GLIMPSE that are in the sightline to the CMZ, we have selected those few thousand stars with I 5 7.5 mag. We then use results of J, K, L photometry to eliminate likely late-type stars, whose complex photospheric spectra would make it difficult to isolate the weak interstellar lines of H . For the few hundred stars thus chosen, we are obtaining medium resolution ( ) spectroscopy from 1.6 to 2.4 m. The presence or absence of CO overtone bands (2-0, 3-1, 4-2, ...) near 2.3 microns allow us clearly discriminate the hot stars from late-type stars. So far we have observed 84 candidate hot stars and found a dozen that are usable for H spectroscopy. Some of them are probably foreground stars. High resolution spectroscopy of low excitation CO lines and of H are required to establish the is located. The completion of this positions of these stars along the line of sight and the environments in which any H project will take several years. Quite apart from the application to the H spectroscopy, finding bona fide young stars near the Galactic center is itself an interesting discovery. a M. Goto, Usuda, Nagata, Geballe, McCall, Indriolo, Suto, Henning, Morong, and Oka, ApJ, 688, 306 (2008) RG06 10 min 2:55 THE ORIGINS OF ETHYL CYANIDE AND DIMETHYL ETHER IN THE INTERSTELLAR MEDIUM DOUGLAS N. FRIEDEL, Department of Astronomy, University of Illinois, 1002 W. Green St., Urbana, IL 61801; SUSANNA L. WIDICUS WEAVER, Department of Chemistry, Emory University, 1515 Dickey Drive, Atlanta, GA 30322. Orion-KL displays the most well-defined case of chemical differentiation, where the emission signatures for oxygen- and nitrogen-bearing organic molecules are spatially distinct. We have been conducting millimeter imaging studies of Orion at various beam sizes in order to investigate the distributions of several large molecular species. Such observations reveal the relative location of these molecules within the region, and also indicate whether their emission is coincident with continuum sources, shocks, or other energy sources within the Orion-KL complex. We will present the results of our recent sub-arcsecond resolution CARMA observations of the shock tracer SiO, the dust continuum, and two of the most abundant molecules in the region, ethyl cyanide and dimethyl ether. We will discuss the implications of these observations on the formation and destruction mechanisms for large organic molecules in star forming regions. Intermission 249 RG07 NEW LABORATORY MEASUREMENTS OF RHOMBOIDAL SiC 15 min 3:20 CARL A. GOTTLIEB and PATRICK THADDEUS, Harvard-Smithsonian Center for Astrophysics, 60 Garden St., Cambridge, MA 02138, and School of Engineering & Applied Sciences, Harvard University, 29 Oxford St., Cambridge, MA 02138. Rhomboidal SiC , the highly polar planar ring with C symmetry and a transannular C—C bond, was detected in our laboratory about 10 years ago, a and soon afterwards was identified with a radio telescope in the expanding envelope of IRC+10216.b Recently a sensitive spectral line survey of IRC+10216 was made with the Submillimeter Array (SMA) in the GHz range with a synthesized beam. Many new lines were detected in this survey. Most are from high rotational transitions of molecules that are known in IRC+10216, but some of the lines are quite narrow and more than 10 of these are unassigned. c In support of the SMA observations we have extended the earlier laboratory measurements by Apponi et al. from 286 GHz and ' , to 450 GHz and ' from rotational levels as high as 825 K above ground. As a result uncertainties in the predicted spectrum for lines with high ' have been reduced by as much as two orders of magnitude, which should aid the assignment of SiC in the SMA survey and in future observations with ALMA. a A. J. Apponi, M. C. McCarthy, C. A. Gottlieb, and P. Thaddeus, Journ. Chem. Phys. 111, 3911 (1999). J. Apponi, M. C. McCarthy, C. A. Gottlieb, and P. Thaddeus, Astrophys. Journ. Lett. 516, L103 (1999). c N. A. Patel, K. H. Young, S. Brünken, R. W. Wilson, P. Thaddeus, K. M. Menten, M. Reid, M. C. McCarthy, Dinh-V Trung, C. A. Gottlieb, and A. Hedden, Astrophys. Journ., in press (2009). b A. RG08 THE ROTATIONAL SPECTRA OF THE SILICON ISOTOPIC SPECIES OF SiCC 10 min 3:37 DAMIAN L. KOKKIN, CARL A. GOTTLIEB, MICHAEL. C. McCARTHY, and PATRICK THADDEUS, Harvard-Smithsonian Center for Astrophysics, 60 Garden St., Cambridge, MA 02138, and School of Engineering & Applied Sciences, Harvard University, 29 Oxford St., Cambridge, MA 02138; and SANDRA BRÜNKEN, Laboratoire de Chimie Physique Mol éculaire, École Polytechnique Fédérale de Lausanne, Station 6, CH-1015 Lausanne, Switzerland. Until this work, the rotational spectra of the silicon isotopic species of SiCC were based almost entirely on astronomical frequencies, because only the fundamental transition SiC and SiC had been measured in the laboratory. a We have now derived precise rotational and centrifugal distortion constants from laboratory measurements of 35 transitions of each isotopic species between 140 and 360 GHz with & and ' . The rotational spectra calculated with the laboratory measured constants are about two orders of magnitude more accurate than that of He et al., b who determined the spectroscopic constants from about 20 lines of SiC and of SiC in the wide-line source IRC+10216. The new laboratory measurements should aid assignment of the silicon isotopic species of SiCC in the spectral line survey of IRC+10216 with the SMA, c and in future observations with ALMA. a R. D. Suenram, F. J. Lovas, and K. Matsumura, Astrophys. Journ. Lett. 342, L103 (1989) H. He, Dinh-V-Trung, S. Kwok, H. S. P. Müller, Y. Zhang, T. Hasegawa, T. C. Peng, and Y. C. Huang, Astrophys. Journ. Suppl. Ser., 177, 275 (2008). c N. A. Patel, K. H. Young, S. Brünken, R. W. Wilson, P. Thaddeus, K. M. Menten, M. Reid, M. C. McCarthy, Dinh-V-Trung, C. A. Gottlieb, and A. Hedden, Astrophys. Journ., in press (2009). b J. 250 RG09 15 min 3:49 ELECTRONIC SPECTROSCOPY OF COMBUSTION GENERATED SMALL PAH’s BY R2PI FROM 207 to 320 nm Y. CARPENTIER, T. PINO and PH. BRÉCHIGNAC, Laboratoire de Photophysique Mol éculairea , CNRS, Bât 210, Université Paris-Sud, F91405 Orsay Cedex, France. The Polycyclic Aromatic Hydrocarbons (PAHs) could be responsible for the so-called UV bump near 217 nm in the interstellar extinction curve. In order to test this conjecture, the electronic spectra of gas phase relevant species have to be investigated. This paper will present the results of such measurements obtained using two-photon resonantly enhanced laser ionization. The newly built experimental set-up called ”Nanograins” has been used to generate a non-biased ensemble of PAHs from the combustion of hydrocarbons in a premixed low-pressure flame thanks to a flat burner. The combustion products are extracted from the flame by means of a sampling quartz cone, then mixed with a buffer gas to flow through a nozzle and skimmer assembly before being UV laser ionized further downstream within the acceleration zone of an orthogonal linear time-of-flight mass spectrometer. Wavelength scanning of the UV laser allows the simultaneous recording of many species thanks to the mass resolution. The obtained spectra will be presented and commented upon, with particular attention to the region of the interstellar extinction bump. a Member of the Fédération de Recherche Lumière Matière RG10 15 min 4:06 ELECTRONIC SPECTROSCOPY OF VUV IRRADIATED PAH CONTAINING INTERSTELLAR WATER ICE J. BOUWMAN and H. LINNARTZ, Raymond and Beverly Sackler Laboratory for Astrophysics, Leiden Observatory, Leiden University, N. Bohrweg 2, 2333CA Leiden; L. J. ALLAMANDOLA, NASA-Ames Research Center, Space Science Division, Moffet Field, CA 94035. Polycyclic aromatic hydrocarbons (PAHs) are believed to be present in space and to play a key role in inter- and circumstellar reaction schemes. Their presence is evidenced by characteristic infrared emission features following UV excitation, but unambiguous identifications have not been possible mainly because of spectral congestion and overlap. Here we present a new laboratory experiment that provides optical fingerprint spectra of PAHs in water ice. As the technique is fast - with a subsecond time resolution - also reactions in the ice following energetic processing can be monitored at astrophysically relevant temperatures (10 to 300 K). For this, the ice is irradiated with a special VUV source that produces Lyman- radiation to simulate the interstellar radiation field. Spectral changes show that PAH-ions and reaction products involving dissociation products from the water matrix (PAH-OH and its ions) are readily formed. The technique is demonstrated on the example of pyrene (C H ) in water ice. 251 RG11 15 min 4:23 RESULTS FROM VUV SPECTROSCOPY OF NEUTRAL DIAMONDOID MOLECULES AND IR SPECTROSCOPY OF THE CATIONIC SPECIES OLIVIER PIRALI, SÉVERINE BOYÉ-PERONNE and STÉPHANE DOUIN, Laboratoire de Photophysique Moléculaire, Université Paris-Sud, 91405 Orsay Cedex, France; HECTOR ALVARO GALUE and JOS OOMENS, FOM-Institute for Plasma Physics Rijnhuizen, NL 3430 BE Nieuwegein, The Netherlands; GUSTAVO GARCIA, LAURENT NAHON and MICHEL VERVLOET, Synchrotron SOLEIL, L’Orme des Merisiers Saint-Aubin, 91192 Gif-sur-Yvette, France. Due to their stability, diamond materials are expected to be present in different environments of the interstellar medium a. Indeed, nanometer size diamond cristals have been extracted from carbonaceous chondrites b and two emission features (observed at 3.43 m and 3.53 m) in the spectra of HD 97048 and Elias1 have been assigned to these species c . Despite this high astrophysical relevance, very few is known about the structural properties and dynamics of the molecular building blocks of larger species : the diamondoid molecules. These molecules consist of sp3 hybridized carbon cages where dangling bonds are terminated by hydrogen atoms. The infrared spectra of neutral molecules conforted the assignment of the 3.43 m and 3.53 m emission features to nanometer size diamondoid systems d . In order to improve the understanding of the possible process leading to the IR emission features, we recorded the IR spectra of the deshydrogenated cationic species of adamantane, diamantane and triamantane (using Infrared Multi Photon Dissociation technique with the free electron laser FELIX) as well as the VUV spectra of adamantane and diamantane (obtained thanks to the Threshold Photo Electron Photo Ion Coincidence technique at the DESIRS beamline of the synchrotron SOLEIL). We will show the results of these spectra and the preliminary analysis. a Saslaw and Gaustad, Nature, 221, 160 (1969) et al., Nature, 326, 160 (1987) c van Kerckhoven et al., Astronomy and Astrophysic, 384, 568 (2002) d Pirali et al., The Astrophysical Journal, 661, 919 (2007) b Lewis RG12 15 min 4:40 SUBMILLIMETER-WAVE OBSERVATIONS OF C N IN AN EXTENDED NEGATIVE GLOW DISCHARGE T. AMANO, Department of Chemistry, University of Waterloo, Waterloo, ON, Canada N2L 3G1. Extended negative glow and hollow anode discharges are found to be good sources of negative ions, such as CN , C H , and C H , for observations of pure rotational lines in the submillimeter-wave region a. Thaddeus et al. b detected C N in a glow discharge in HC N diluted in Ar buffer gas, and its rotational lines up to 378 GHz (& ) were measured. In the present investigation, this anion has been observed in an extended negative glow discharge in a gas mixture of C N ( mTorr) and C H ( mTorr) in Ar buffer gas of mTorr at the cell wall temperature of 230 K. The optimum discharge current was 2-4 mA with 250 Gauss longitudinal magnetic field. The rotational lines of up to & in the 495 GHz region have been measured, and the improved rotational and centrifugal distortion constants are obtained. In the discharge optimum for production of C N , neither CN nor C N was detected with a similar signal accumulation time used for observations of the anion. However, this reaction has been found to be an excellent source for HC N, and the dominant formation mechanism of C N is likely to be the dissociative electron attachment to HC Nc . The radiative association of C N with electrons seems to be unlikely at least for the extended negative glow discharge. Apparently HC N is synthesized by a fast neutral and neutral reaction d, % It is interesting to see that an isomer, HCCNC, is also detected in the discharge, although the number density of this species is found to be about two orders of magnitude smaller than that of HC N. Another isomer, HNCCC, has also been observed with much weaker signal intensity. This species might have been produced by the dissociative recombination reaction of HC NH with electrons, although the detection of this cation has not been successful in this type of discharge. a T. Amano, J. Chem. Phys., 129, 244305 (2008) Thaddeus et al.,Astrophys. J., 677,1132-1139 (2008) c K. Graupner et al., New J. Phys., 8,117 (2006) d I. R. Sims et al.,Chem. Phys. Lett., 211, 461-468(1992); D. E. Woon and E. Herbst,Astrophys. J., 477, 204-208(1997) b P. 252 RG13 SHOCK FORMATION OF INITIAL MOLECULAR ICE MANTLES 15 min 4:57 GEORGE E. HASSEL, Department of Physics, The Ohio State University, Columbus, OH 43210; ERIC HERBST, Departments of Physics, Astronomy, & Chemistry, The Ohio State University, Columbus, OH 43210; EDWIN A. BERGIN, Department of Astronomy, University of Michigan, 825 Dennison Building, Ann Arbor, MI 48109. We use a gas-grain chemical network to investigate the initial synthesis of molecular ices as a cold molecular cloud forms behind a shock in the diffuse interstellar medium. The reaction network includes newly measured rates of photodesorption. The results show that CO is first produced in the gas phase in early stages of cloud birth. This is followed by concurrent formation of water ice on the grain and CO accretion to the grain surface from the gas, at intermediate values of the visual extinction. The production of CO occurs on grains, via both diffusive processes and the Eley-Rideal mechanism. The formation of CH ice is inhibited by the gas phase formation of CO. These results show reasonable agreement with detection thresholds for the major ice species, and show best agreement with the observed ice composition along quiescent lines of sight in the Taurus dark cloud for values of " of 2-3 mag. When the dense core begins to condense from the cloud, the initial state is not dominated by a gas rich in ionized C, as typically assumed. RG14 15 min 5:14 AB INITIO QUANTUM CALCULATIONS OF REACTIONS IN ASTROPHYSICAL ICES: ACETALDEHYDE AND ACETONE WITH AMMONIA L. CHEN and D. E. WOON, Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana IL 61801. Complex organic molecules, including amino acid precursors, have been observed in young stellar objects a . Both laboratory and theoretical studies have shown that ice chemistry can play an important role in low-temperature synthetic pathways, with water serving as a catalyst that can significantly enhance reaction rates by lowering barriers or eliminating them altogether. Reactions between carbonyl species and ammonia are particularly promising, as shown in previous studies of the formaldehyde-ammonia reaction b. In this study, we explore the reactions of ammonia with two larger carbonyl species, acetaldehyde and acetone, embedded in a water ice cluster. To examine the explicit impact of the water, we gradually increase the size of the cluster from 4H O to 12H O. Cluster calculations were performed at the MP2/6-31+G or B3LYP/6-31+G level. In order to account for the electrostatic contribution from bulk ice, the Polarizable Continuum Model (PCM) and Isodensity Surface Polarized Continuum Model (IPCM) were used to model reaction field solvation effects. For both acetaldehyde and acetone, the reactant is a charge transfer complex (a partial charge-transfer complex in small clusters and full proton-transfer complex in larger clusters). Rearrangement to amino-hydroxylated products can occur by surmounting a small reaction barrier. Stereo-selectivity is observed in the case of acetaldehyde. a P. Ehrenfreund and S. B. Charnley, Ann. Rev. Astron. Astrophys. 38, 427 (2000). A. Schutte, L. J. Allamandola, and S. A. Sandford, Science 259, 1143 (1993); Icarus 104, 118 (1993); D. E. Woon, Icarus 142, 550 (1999); S. P. Walch, C. W. Bauschicher, Jr., A. Ricca and E. L. O. Bakes, Chem. Phys. Lett, 333, 6 (2001). b W. 253 RG15 15 min 5:31 MICROWAVE SPECTRA OF METHYL FORMATE ISOTOPOMER (HCOO CH ) HARUKA TACHI, KAORI KOBAYASHI, SHOZO TSUNEKAWA, , Department of Physics, University of Toyama, 3190 Gofuku, Toyama, 930-8555 Japan; MEGUMI KUWANO, MASAHARU FUJITAKE, NOBUKIMI OHASHI, Kanazawa University, Japan; NAOTO HAYASHI, and HIROYUKI HIGUCHI, Department of Chemistry, University of Toyama, 3190 Gofuku, Toyama, 930-8555 Japan. Methyl formate is a well-known interstellar molecule found in the star-forming region. One possible methyl formate production reaction is the reaction of methanol with other chemical species. Since the methyl rotor is originated from the methanol and CH OH has already been identified in space, it is quite likely to detect HCOO CH in the near future. The microwave spectra of the methyl formate isotopomer (HCOO CH ) could provide the rest frequencies as well as some indication about the production mechanism. We observed the microwave spectra of HCOO CH by means of the FT-microwave spectrometer and the conventional source modulation spectrometer. The lines in the ground state were assigned and analyzed based on Hougen’s tunneling matrix formulation. RG16 15 min 5:48 CH CH : TORSIONAL SPECTRUM OF A 2-STATE FREQUENCY ANALYSIS OF THE TORSIONAL BANDS AND THE VIBRATIONAL FUNDAMENTAL L. BORVAYEH, N. MOAZZEN-AHMADI, Department of Physics and Astronomy, University of Calgary, Calgary, AB T2N 1N4, CANADA; V.-M. HORNEMAN, Department of Physical Sciences, University of Oulu, PO Box 3000, Fin-90014, Oulu, Finland. The far-infrared spectrum of CH CH is studied between cm at an effective resolution of % % cm using a Bruker IFS-120 HR . Observation of the torsional fundamental ( cm ) and the torsional hot band ( cm ), together with the lowest frequency vibrational fundamental (% cm ), also obtained with the same spectrometer at an effective resolution of % cm , gives information on the torsional stack of the ground vibrational state and that for 1 state. The frequencies are analysed in terms of a 2-state fit to determine the torsion mediated Coriolis interactions between the torsional stacks. A comparison is made with a 2-state fit of similar data for CH CH % 254 RH. MICROWAVE THURSDAY, JUNE 25, 2009 – 1:30 PM Room: 1000 McPHERSON LAB Chair: BRIAN DIAN, Purdue University, West Lafayette, Indiana RH01 15 min 1:30 AN ACOUSTIC DEMONSTRATION MODEL FOR CW AND PULSED SPECTROSOCOPY EXPERIMENTS TORBEN STARCK, HEINRICH MÄDER, Institut für Physikalische Chemie, Universität Kiel, Olshausenstr. 40, D-24098 Kiel, Germany; TREVOR TRUEMAN, and WOLFGANG J ÄGER, Department of Chemistry, University of Alberta, Edmonton, AB, Canada T6G 2G2. High school and undergraduate students have often difficulties if new concepts are introduced in their physics or chemistry lectures. Lecture demonstrations and references to more familiar analogues can be of great help to the students in such situations. We have developed an experimental setup to demonstrate the principles of cw absorption and pulsed excitation - emission spectroscopies, using acoustical analogues. Our radiation source is a speaker and the detector is a microphone, both controlled by a computer sound card. The acoustical setup is housed in a plexiglas box, which serves as a resonator. It turns out that beer glasses are suitable samples; this also helps to keep the students interested! The instrument is controlled by a LabView program. In a cw experiment, the sound frequency is swept through a certain frequency range and the microphone response is recorded simultaneously as function of frequency. A background signal without sample is recorded, and background subtraction yields the beer glass spectrum. In a pulsed experiment, a short sound pulse is generated and the microphone is used to record the resulting emission signal of the beer glass. A Fourier transformation of the time domain signal gives then the spectrum. We will discuss the experimental setup and show videos of the experiments. 255 RH02 15 min 1:47 WHERE MILLIMETER WAVE SPECTRA ARE SENSITIVE TO SMALL ELECTRIC FIELDS: HIGH RYDBERG STATES OF XENON AND THEIR HYPERFINE STRUCTURES MARTIN SCHÄFER, MATTHIAS RAUNHARDT, and FRÉDÉRIC MERKT, ETH Zürich, Laboratorium f ür Physikalische Chemie, Wolfgang-Pauli-Strasse 10, 8093 Z ürich, Switzerland. In the range 0–45 cm below the ionization limit, the separation between adjacent electronic states (Rydberg states with principal quantum number 8 ) of atoms and molecules is smaller than 2 cm . In order to resolve the fine or hyperfine structure of these states, it is necessary to combine high-resolution vacuum ultraviolet (VUV) laser radiation, which is required to access the Rydberg states from the ground state, with millimeter wave radiation. a Such double-resonance experiments have been used to study the hyperfine structure of high Rydberg states of Kr b , H c , or D d . Millimeter wave transitions (240–350 GHz) between > ( > ) Rydberg states of different xenon isotopes were detected by pulsed field ionization followed by mass-selective detection of the cations. Because of the high polarizability of high- Rydberg states ( , MHz cm V for ), it is necessary to reduce the electric stray fields to values of the order of mV/cm (or less) in order to minimize the (quadratic) Stark shift of the millimeter wave transitions. Some p and d Rydberg states of Xe are nearly degenerate and efficiently mixed by small stray fields, making it possible to observe transitions forbidden by the > selection rule or transitions exhibiting a linear Stark effect, which is typical for the degenerate high-> Rydberg states. Multichannel quantum defect theory (MQDT) was used to analyze the millimeter wave data and to determine the hyperfine structures of the P ground electronic states of Xe and Xe . a C. Fabre, P. Goy, S. Haroche, J. Phys. B: Atom. Mol. Phys. 10, L183–189 (1977). F. Merkt, A. Osterwalder, Int. Rev. Phys. Chem. 21, 385–403 (2002). M. Schäfer, M. Andrist, H. Schmutz, F. Lewen, G. Winnewisser, F. Merkt, J. Phys. B: At. Mol. Opt. Phys. 39, 831–845 (2006). b M. Schäfer, F. Merkt, Phys. Rev. A, 74, 062506 (2006). c A. Osterwalder, A. Wüest, F. Merkt, Ch. Jungen, J. Chem. Phys., 121, 11810–11838 (2004). d H. A. Cruse, Ch. Jungen, F. Merkt, Phys. Rev. A 77, 04502 (2008). RH03 15 min 2:04 BREAKDOWN OF THE REDUCTION OF THE ROVIBRATIONAL HAMILTONIAN : THE CASE OF S O F L. MARGULÈS, J. DEMAISON, Laboratoire PhLAM, CNRS UMR 8523, Universit é de Lille 1, Bat. P5, 59655 Villeneuve d’Ascq Cedex, France.; A. PERRIN, Laboratoire Inter Universitaire des Systemes Atmosphériques, CNRS UMR 7583, Université Paris 12, 61 Av du General de Gaulle, 94010 Cr éteil Cedex France.; I. MERKE, ; Institute für Physikalische Chemie, RWTH Aachen, 52056 Aachen, Germany; H. WILLNER, Anorganische Chemie, FB C, Universit ät-GH Wuppertal, 42097 Wuppertal, Germany; M. ROTGER, Groupe de Spectromtrie Moléculaire et Atmosphrique, CNRS UMR 6089, Moulin de la Housse, BP 1039, Cases 16-17, 51687 Reims Cedex 2, France; and V. BOUDON, Institut Carnot de Bourgogne, UMR CNRS 5209, 9 avenue Alain Savary, BP 47870, 21078 Dijon Cedex, France. The ground state rotational spectrum of the near-spherical top molecule S O F (sulfuryl fluoride) has been measured from 50 to 700 GHz. As for the parent isotopologue, S O F a , it was necessary to use a non-reduced Hamiltonian in order to obtain a satisfactory fit. It was possible to determine six quartic centrifugal distortion constants (instead of five for a standard asymmetric top) and an additional sextic constant could also be determined. This ground state level has also been analysed thanks to a tensorial formalism developed in Dijon. Only two tensorial sextic constants are fixed to zero, all others have been adjusted. Although S O F is less spherical than S O F , the analysis was more difficult. It is partly due to the fact that S O F is oblate whereas S O F is prolate. The experimental quartic centrifugal distortion constants were found in good agreement with those calculated from the force field, confirming the correctness of the analysis. a K. Sarka, J. Demaison, L. Margulès, I. Merke, N. Heineking, H. Bürger, and H. Ruland, J. Mol. Spectrosc., 200, 55 (2000) 256 RH04 10 min 2:21 EXTENDED TOWNES-DAILEY ANALYSIS OF THE NUCLEAR QUADRUPOLE COUPLING TENSOR STEWART E. NOVICK, Department of Chemistry, Wesleyan University, Middletown, CT 06459. One simple way to understand nuclear quadrupole coupling constants is by invoking the model of Townes and Dailey. a This model, involving the field gradients generated by p electrons, has usually been used to estimate the fractional ionic character of diatomic molecules from a single nuclear quadrupole coupling constant. We will extend the model to three dimensions for polyatomic molecules and use it to rationalize the perhaps unexpected nuclear quadrupole coupling tensor for molecules such as monobromogermylene (HGeBr) and compare this simple calculation with ab initio results. a C. H. Townes, B. P. Dailey, J. Chem. Phys. 17, 782 (1949) RH05 15 min 2:33 A NEW PROGRAM FOR NON-EQUIVALENT TWO-TOP INTERNAL ROTORS WITH A C FRAME I. KLEINER, Laboratoire Interuniversitaire des Syst èmes Atmosphériques, CNRS et Universités Paris 7 et Paris 12, 61 av. Général de Gaulle, 94010, Créteil, France; J. T. HOUGEN, Optical Technology Division, National Institute for Standards and Technology, Gaithersburg, MD 20899-8441, USA. We have written a new program to calculate and fit torsion-rotation transitions in molecules containing two inequivalent methyl tops (C ) and having the rest of the atoms lying in a plane of symmetry. We based our work on the theoretical model and Hamiltonian described by Ohashi et al for the N-methylacetamide molecule a. In the absence of top-top interactions, each asymmetric top energy levels splits into AA, AE, EA and EE components where the individual letters A and E indicate the symmetry species of the wave function with respect to internal rotation of one of the methyl tops. The pair of letters taken together indicates the species in the G permutation-inversion group appropriate for the molecule, so AA, AE, EA, and EE correspond to A (or A ), E , E and E E , respectively. In the previous study, the torsion-rotation Hamiltonian was diagonalized directly in a one-step process using torsion-rotation functions & ' 8 8 8 where m and m represent the free-rotor basis functions for top 1 and top 2. The one-step diagonalization made however the least-squares fitting of moderate J values very slow, even for rather small values of m and m . Our goal is to write a code which will be faster and which allows us to reach higher J values. We follow a two-step procedure to diagonalize the Hamiltonian and implemented a banded-matrix diagonalization routine in order to speed up the code. We tested the code with the published N-methylacetamide Fourier-transform microwave data. The principles of the method, as well as the limitations will be discussedb . a N. b IK Ohashi, J. T. Hougen, R. D. Suenram, F.J. Lovas, Y. Kawashima, M. Fujitake and J. Pyka, J. Mol. Spectrosc., 227, 28-42 (2004) thanks the ANR-08-BLAN-0054 for financial support 257 RH06 15 min 2:50 PROTON DONOR/ACCEPTOR PROPENSITIES OF AMMONIA: ROTATIONAL STUDIES OF ITS MOLECULAR COMPLEXES WITH ORGANIC MOLECULES BARBARA M. GIULIANO, ASSIMO MARIS, SONIA MELANDRI, LAURA B. FAVERO, LUCA EVANGELISTI and WALTHER CAMINATI, Dipartimento di Chimica ”G. Ciamician” dell’Universit à, Via Selmi 2, I-40126 Bologna, Italy. We studied the rotational spectra of the adducts of ammonia with several organic molecules, namely tert-butanol, a glycidol,b ethyl alcohol, anisol and 1,4-difluorobenzene. The adducts with glycidol and ethanol have been observed for both conformers of the substrate molecule. Based on the rotational and N quadrupole coupling constants of the various complexes, we found a considerably different behaviour of ammonia, with respect to water, in its proton donor/acceptor double role. In the interaction with the three alcohol molecules, NH acts as a proton acceptor and the OH groups as a proton donor. However, in the case of glycidol-NH , a secundary N-H O interaction occurrs between ammonia and the ether oxygen. This interaction generates a sizable V barrier to the internal rotation of the NH moiety, while NH undergoes a free rotation in tert-butanol-NH and in ethanol-NH . As to the anisole-NH and 1,4-difluorobenzene-NH complexes, the NH group explicits its double proton donor/acceptor role, although through two weak (C % -H N and N-H $ ) H-bonds. There is, however, an important difference between the two complexes, because in the first one NH lies out of the aromatic plane, while in the second one it is in the plane of the aromatic ring. a B. b B. M. Giuliano, M. C. Castrovilli, A. Maris, S. Melandri, W. Caminati and E. A. Cohen, Chem.Phys.Lett., 2008, 463, 330 M. Giuliano, S. Melandri, A. Maris, L. B. Favero and W. Caminati, Angew.Chem.Int.Ed., 2009, 48, 1102 Intermission RH07 15 min 3:30 DESIGN AND CHEMICAL APPLICATION OF CHIRPED-PULSE MILLIMETER-WAVE SPECTROSCOPY G. B. PARK, A. H. STEEVES, K. KUYANOV-PROZUMENT, A. P. COLOMBO, and R. W. FIELD, Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139; J. L. NEILL and B. H. PATE, Department of Chemistry, University of Virginia, Charlottesville, VA 22904. Chirped-Pulse Millimeter-Wave (CPmmW) Spectroscopy is the first truly broadband Fourier-transform technique for highresolution spectroscopy in the millimeter-wave region. The design is based on the pioneering Fourier-Transform ChirpedPulse Microwave (FT-CPMW) spectrometer developed at the University of Virginia, which operates at frequencies up to 20 GHz. We have built an instrument that covers the 70-102 GHz frequency region and can acquire up to 12 GHz bandwidth of spectrum in a single shot. Preliminary tests indicate a significant advantage in spectral acquisition time over existing millimeter-wave spectrometers, and further improvement to the sensitivity is expected as broadband millimeter-wave power amplifiers become affordable. The ability to acquire broadband Fourier-transform millimeter-wave spectra enables rapid measurement of survey spectra at sufficiently high resolution to measure diagnostically important electronic properties and also allows the accurate determination of relative line strengths. As an example of the usefulness of this tool to physical chemists, the nascent vibrational distribution of products from the photolysis of acrylonitrile at 193 nm is investigated and preliminary results are discussed. 258 RH08 15 min 3:47 BROADBAND CHIRPED-PULSE FOURIER-TRANSFORM MICROWAVE SPECTROSCOPIC INVESTIGATION OF THE STRUCTURES OF THREE DIETHYLSILANE CONFORMERS AMANDA L. STEBER, DANIEL A. OBENCHAIN, REBECCA A. PEEBLES, and SEAN A. PEEBLES, Department of Chemistry, Eastern Illinois University, 600 Lincoln Avenue, Charleston, IL 61920; JUSTIN L. NEILL, MATT T. MUCKLE, and BROOKS H. PATE, Department of Chemistry, University of Virginia, Charlottesville, VA 22904; GAMIL A. GUIRGIS, Department of Chemistry and Biochemistry, The College of Charleston, Charleston, SC 29424. The rotational spectrum of diethylsilane has been assigned using broadband chirped-pulse Fourier-transform microwave (CP-FTMW) spectroscopy. Previously, Fourier-transform microwave rotational spectra were observed using a BalleFlygare type instrument for the Si isotopologues of the gauche-gauche, trans-gauche, and trans-trans conformers. a In the present study, a broadband microwave spectrum was obtained at the University of Virginia, taking advantage of the ability to perform deep signal averaging to increase the measurement sensitivity. To obtain a full structural determination of the conformers of this molecule, spectra for the Si, Si, and single C substitutions for the gauche-gauche, the trans-gauche, and the trans-trans species were assigned. Substitution ( ) structures and inertial fit ( ) structures were determined and a comparison between the experimental and ab initio structures will be presented. For the Si isotopologues, the percent differences between the experimental and ab initio rotational constants are less than 1.5% for the trans-trans and trans-gauche and are between 2.0 and 5.0% for the gauche-gauche conformer. The structural parameters will be compared between this molecule, diethylgermane and other silicon containing molecules and the relative abundances of the three conformers will be discussed. a S.A. Peebles, M.M. Serafin, R.A. Peebles, G.A. Guirgis, and H.D. Stidham J. Phys. Chem. A, (2009), DOI: 10.1021/jp811049n. RH09 15 min 4:04 THE PURE ROTATIONAL SPECTRA OF CrS SULFIDES (X ): CONTINUED STUDIES OF THE 3d TRANSITION METAL R. L. PULLIAM, A. J. HIGGINS, and L. M. ZIURYS, Department of Chemistry, Department of Astronomy, Steward Observatory, University of Arizona, Tucson, AZ 85721. The pure rotational spectrum of CrS has been measured in the ground X state using gas-phase direct absorption methods in the frequency range of 280-405 GHz. The molecule was created by the reaction of chromium vapor, sublimed in a Broida oven, with hydrogen sulfide gas. All five spin components were observed in eleven rotational transitions, and lambda-doubling splitting were resolved in the , = 0, 1 and 2 ladders. The data were fit with a Hunds case(a) Hamiltonian and rotational, spin-orbit, spin-spin, and lambda-doubling constants have been established. A bond length of 2.0781 Å was derived from the data. Using the lambda-doubling parameters, the energy difference between the ground X and excited state was estimated to be 1400 cm . RH10 SUBMILLIMETER SPECTROSCOPY OF ZnOH SPECIES (X A ): 15 min 4:21 STRUCTURE AND BONDING IN 3d HYDROXIDE L. N. ZACK and L. M. ZIURYS, Department of Chemistry, Department of Astronomy, and Steward Observatory, University of Arizona, Tucson, AZ, 85721. The ZnOH radical (X A ) has been observed in the laboratory using mm/sub-mm direct-absorption techniques. This is the first gas-phase laboratory spectroscopic study of this radical. ZnOH was produced by reacting zinc vapor with H O or H O under DC discharge conditions. Multiple rotational transitions have been recorded in the 400-540 GHz range that clearly exhibit K-ladder structure, indicative of a bent molecule. the pattern has been observed in three zinc isotopologues: ZnOH, ZnOH, and ZnOH. Each line consists of spin-rotation doublets with a splitting of 180190 MHz, characteristic of zinc. The data are currently being analyzed and rotational and spin-rotation constants will be presented. The bent geometry suggests predominantly covalent bonding between zinc and oxygen. 259 RH11 MICROWAVE SPECTRA AND STRUCTURES OF H S-CuCl AND H S-AgCl. 15 min 4:38 N. R. WALKER, D. WHEATLEY AND A. C. LEGON, School of Chemistry, University of Bristol, Bristol, BS8 1TS, U.K.. An FT-MW spectrometer coupled to a laser ablation source has been used to obtain the pure rotational spectra of H S-CuCl and H S-AgCl. Both molecules are generated via laser ablation (532 nm) of a metal rod in the presence of CCl and argon and are stabilized by supersonic expansion. Rotational constants (B , D ) have been measured for four isotopomers of each molecule with substitutions at the metal and chlorine atoms in each case. The spectrum of each molecule is consistent with a linear arrangement of sulphur, metal and chlorine atoms. Nuclear quadrupole coupling constants have been measured for the chlorine atom in each molecule and also for copper in H S-CuCl. Nuclear spin-rotation constants have been determined for the copper atom in H S-CuCl. The observed trends are consistent with results previously reported for Ar-MX, OC-MX (where M is a Group 11 metal atom and X is a halogen) and N -CuF. Further experiments are being performed to obtain and assign the spectra of D S-CuCl and D S-AgCl. These data will allow determination of the angle defined between the axis of the D S molecule and that of the metal chloride unit. RH12 MICROWAVE SPECTROSCOPY OF THE HEAVY-ATOM CARBENE ANALOGS: HSiI and DSiI 15 min 4:55 LU KANG, Department of Natural Sciences, Union College, Barbourville, KY 40906; MOHAMMED A. GHARAIBEH, DENNIS J. CLOUTHIER, Department of Chemistry, University of Kentucky, Lexington, KY 40506; STEWART E. NOVICK, Department of Chemistry, Wesleyan University, Middletown, CT 06459. The pure rotational spectra of 6 silicon isotopologues, of HSiI and of DSiI have been recorded in natural abundance by pulsed-jet Fourier transform microwave (FTMW) spectroscopy. Neon was passed over dry ice cooled H SiI or D SiI and introduced into the pulsed valve of the FTMW spectrometer. The HSiI and the DSiI were produced in-situ with a 1000 V DC-discharge nozzle. Only -type transitions can be observed from 6 - 26 GHz; ' = 0 transitions for the HSiI and ' = 0 and 1 transitions for the DSiI isotopologues. All observed transitions were assigned unambiguously. The molecular structure and chemical bonding of this heavy atom carbene will be discussed. RH13 15 min 5:12 SPECTROSCOPIC CHARACTERIZATION OF HIGHLY ENERGETIC ISOFULMINIC ACID, HONC, BY EXPERIMENTAL AND THEORETICAL APPROACHES M. C. MCCARTHY, P. THADDEUS, Harvard-Smithsonian Center for Astrophysics, 60 Garden St., Cambridge, MA 02138, and School of Engineering and Applied Sciences, Harvard University, 29 Oxford St., Cambridge, MA 02138; MIRJANA MLADENOVIC AND MARIUS LEWERENZ, Universit é Paris-Est, Laboratoire Modélisation et Simulation Multi Echelle, MSME FRE3160 CNRS, 5 bd Descartes, 77454 Marne la Vallée, France. The highly energetic isomer isofulminic acid, HONC, calculated to lie more than 80 kcal/mol above HNCO a , has been characterized spectroscopically in its ground state by a combination of rotational spectroscopy and large-scale CCSD(T) electronic structure calculations. The fundamental rotational transition of HONC, H ONC, HON C, and DONC has been detected in the centimeter-wave band in a molecular beam by Fourier transform microwave spectroscopy, and effective rotational constants and nitrogen and deuterium quadrupole coupling constants have been derived for each isotopic species. All of the measured constants agree very well with those predicted from theoretical calculations of HONC. A number of other electronic and spectroscopic properties of isofulminic acid, including dipole moments, vibrational frequencies, and infrared intensities have also been calculated at the CCSD(T)/cc-pCVQZ level of theory. HONC is a good candidate for detection in space with radio telescopes because of its high polarity and because the more stable isomers, HNCO, HOCN, and HCNO have been identified in rich astronomical sources. a M. S. Schuurman, S. R. Muir, W. D. Allan, and H. F. Schaefer III, J. Chem. Phys. 120, 11587 (2004). 260 RH14 15 min 5:29 ASSIGNMENT OF THE MM- AND SMM-WAVE ROTATIONAL SPECTRA OF RARE ISOTOPOLOGUES OF CYANAMIDE AND THE MOLECULAR GEOMETRY OF NH CN ADAM KRASNICKI, ZBIGNIEW KISIEL, Institute of Physics, Polish Academy of Sciences, Al. Lotnik ów 32/46, 02-668 Warszawa, Poland; BRENDA P. WINNEWISSER, MANFRED WINNEWISSER, Department of Physics, The Ohio State University, Columbus, OH 43210. The cyanamide molecule is one of the prototype systems for the study of the large–amplitude inversion motion at the nitrogen atom, and it is also a potential astrophysical species. The mm-wave, smm-wave, and the far infrared spectra of the parent and the two principal deuterated isotopic species are now known in considerable detail. a b Presently we report an extended analysis of rotational transitions in the and inversion states for 7 rare isotopic species of cyanamide, measured in the 118-650 GHz frequency region on a deuterated sample with natural abundance of carbon and nitrogen. The spectra of five isotopologues: H N CN, HDN CN, D N CN, HD NCN, and HDNC N, have been assigned for the first time. For D NCN and D NC N the knowledge of the rotational spectrum has also been considerably improved relative to preceding work. c d The availability of spectroscopic constants for 12 different isotopic species allowed determination of the complete # and geometriese of cyanamide, providing direct experimental information on the pyramidal nature of the NH group in cyanamide and on the nonlinearity of the NCN segment. The new experimental geometry is compared with results of * 9 99 calculations. a G. Moruzzi et al., J. Mol. Spectrosc., 190, 353-364 (1998). Kisiel et al., 63 OSU International Symposium on Molecular Spectroscopy, WK08, 2008. c J. K. Tyler et al., , 43, 248-261 (1972). d R. D. Brown et al., J. Mol. Spectrosc., 114, 257-273 (1985). e J. K. G. Watson et al., , 196, 102-119 (1999). b Z. 261 RI. ATMOSPHERIC SPECIES THURSDAY, JUNE 25, 2009 – 1:30 PM Room: 1015 McPHERSON LAB Chair: GEOFFREY DUXBURY, University of Strathclyde, Glasgow, Scotland RI01 15 min 1:30 HITRAN2008 EST ARRIV É L. S. ROTHMAN, I. E. GORDON, Harvard-Smithsonian Center for Astrophysics, Atomic and Molecular Physics Division, Cambridge MA 02138-1516, USA. The new HITRAN molecular spectroscopic database has been released a . This latest edition supersedes the previous edition of 2004 and greatly expands on the quantity and quality of spectral line parameters. The effort that went into establishing the new edition involved the participation of a vast number of spectroscopists, laboratories, and funding agencies throughout the world. An overview of the new edition will be presented, with a focus on several molecules of prime importance for atmospheric remote-sensing experiments. Instructions for accessing the database can be found at the web site http://www.cfa.harvard.edu/hitran/ a L.S. Rothman, I.E. Gordon, A. Barbe, D.Chris Benner, P.F. Bernath, et al, “The HITRAN 2008 Molecular Spectroscopic Database,” JQSRT in press (2009). RI02 15 min 1:47 LINE STRENGTH MEASUREMENTS IN THE BAND OF H O Yu. I. BARANOV, Institute of Experimental Meteorology, Lenina 82, Obninsk, Kaluga region 249020, Russia; P. CHELIN, J. ORPHAL, and L. H. COUDERT, LISA, CNRS/Universit és Paris 12 et 7, 61 Avenue du G énéral de Gaulle, 94010 Créteil, France. Spectra of an H O enriched sample of water vapor were recorded from 1780 to 4500 cm , at room temperature, with a Bruker IFS-125 instrument and a liquid nitrogen cooled InSb detector. A single path, 24 cm long, glass cell with ZnSe windows was filled with H O water vapor at 97.1% purity from CDN Isotopes. For the various spectra, pressures ranging from 4.3 to 18.4 Torr were measured with two different MKS Baratron gauges having 10 and 100 Torr pressure limits. The unapodized spectral resolution was 0.002 cm . Line strengths were retrieved from these spectra for transitions belonging to the band with the help of a computer program determining simultaneously line positions, strengths, and linewidths by nonlinear least-squares fitting. The new line strength values were analyzed with those already available for rotational transitions within the ground vibrational statea and for bandb transitions. In order to account for the anomalous centrifugal distortion displayed by water, this line intensity analysis was performed using the Bending-Rotation Hamiltonian approach. c a Toth, J. Molec. Spectrosc. 190 (1998) 379. J. Opt. Soc. Am. B 9 (1992) 462. c Coudert, Wagner, Birk, Baranov, Lafferty, and Flaud, J. Molec. Spectrosc. 251 (2008) 339. b Toth, 262 RI03 15 min 2:04 HALF-WIDTHS, THEIR TEMPERATURE DEPENDENCE, AND LINE SHIFTS FOR THE ROTATION BAND OF H O ROBERT R. GAMACHE AND ANNE L. LARAIA, Department of Environmental, Earth, and Atmospheric Sciences, University of Massachusetts Lowell. Complex Robert-Bonamy (CRB) calculations of the half-width, its temperature dependence, and the line shift have been made for the rotation band transitions of H O for N and O , as the bath molecule. First the atom-atom component of the intermolecular potential was adjusted to reproduce the half-widths of the 22 and 183 GHZ transition determined by Payne et al. (IEEE Trans. Geosci Remote Sens. 2007; 46: 3601-17). Then the line shape parameters were determined at seven temperatures (200., 225., 275., 296., 350., 500., and 700. K) for the H O-N and H O-O systems. The air broadened values were determined at each temperature by the standard method. The half-widths, their temperature dependence, and the line shifts were studied as a function of the rotational quantum numbers. The calculations are compared with measurement. RI04 THEORETICAL CALCULATION OF THE N BROADENED HALF-WIDTHS OF H O 15 min 2:21 Q. MA, NASA/Goddard Institute for Space Studies and Department of Applied Physics and Applied methamatics, Columbia University, 2880 Broadway, New York, NY 10025; R. H. TIPPING, Department of Physics and Astronomy, University of Alabama, Tuscaloosa, AL 35487; R. R. GAMACHE, Department of Environmental, Earth and Atmospheric Science, University of Mass. Lowell, Lowell, MA 01854. The water molecule is the most important Greenhouse gas and thus plays a pivotal role in atmospheric spectra. In addition to accurate intensities and frequencies, one also needs accurate self and foreign half-widths and shifts, and their temperature dependence. Over the years, a large number of theoretical calculations have been carried out by Gamache and his collaborators a. They used the complex Robert-Bonamy theory with a sophisticated interaction potential. The drawback of this method is that one has to carry out the calculations to a high-order perturbation in order to obtain converged results. However, by using the coordinate representation one is able to obviate the perturbation expansion and obtain results corresponding to a high cut-off order b. We present comparisons for the H O-N system for a few lines using the same interaction potential for a comparison between the methods. We conclude that for lines having a large half-width, the convergence is rapid but, on the other hand, for lines with relatively small half-widths the convergence is very slow. a I. E. Gordon et al., J.Q.S.R.T. 108, 389 (2007) and references therein. Ma, R. H. Tipping, and C. Boulet, J. Chem. Phys. 124, 014109 (2006). b Q. RI05 15 min 2:38 TEMPERATURE DEPENDENCES OF MECHANISMS RESPONSIBLE FOR THE WATER VAPOR CONTINUUM Q. MA, NASA/Goddard Institute for Space Studies and Department of Applied Physics and Applied methamatics, Columbia University, 2880 Broadway, New York, NY 10025; R. H. TIPPING, Department of Physics and Astronomy, University of Alabama, Tuscaloosa, AL 35487; C. LEFORESTIER, Institute Charles Gerhardt CNRS-5253, CC1501, Université Montpellier II, 34095 Montpellier, France. The water-vapor continuum plays an important role in the radiation balance in the Earth’s atmosphere. While this absorption has been known for a long time, the physical mechanism responsible is still an open problem. We have recently calculated theoretically both the magnitude and temperature dependence for the three mechanism that have been suggested: the far-wings of allowed lines, collision-induced absorption, and water dimers a b . All three mechanisms depend quadratically on the number density of H O for the self-continuum, and on the product of the densities for the foreign-continuum. However, these three mechanisms have quite differences on the temperature as we will discuss. This analysis may provide us with a method to assess their relative importance in ambient atmospheric measurements. a Q. b C. Ma, R. H. Tipping, and C. Leforestier, J. Chem. Phys. 128, 124313 (2008). Leforestier, R. H. Tipping, and Q. Ma, to be submitted for publication. 263 RI06 15 min 2:55 FIRST ANALYSIS OF THE BAND OF DNO (DEUTERATED NITRIC ACID) IN THE 11 m REGION J.KOUBEK, Institute of Chemical Technology, Department of Analytical Chemistry, Technick á 5,166 28, Praha 6, Czech Republic, and Laboratoire Inter Universitaire des Systemes Atmosph ériques, CNRS, Université Paris 12, 61 Av du General de Gaulle, 94010 Cr éteil Cedex France; A.PERRIN, Laboratoire Inter Universitaire des Systemes Atmosphériques, CNRS, Université Paris 12, 61 Av du General de Gaulle, 94010 Créteil Cedex France; H. BECKERS, H. WILLNER, Anorg. Chemistry, University of Wuppertal, D-42119 Wuppertal, GERMANY. The infrared spectrum of DNO (deuterated nitric acid) was recorded at high resolution (0.0018 cm ) in the 800 -1400 cm region on the Bruker IFR 120 HR Fourier transform spectrometer of Wuppertal. The analysis of the A-type band of DNO centered at 887.656 cm was performed taking use of the ground state parameters achieved by Drouin et al. a . This band is perturbed by several resonances. b a Drouin, Miller, Fry, Petkie, Helminger, Medvedev, J. Mol. Spectrosc. 236 (2006) 2934 The work was supported through the Ministry of Education, Youth and Sports of the Czech Republic (research program LC06071) and scholarship of the French government (Bourse du Gouvernement Francais Bourse de Doctorat en co-tutelle). b Acknowledgment: RI07 15 min 3:12 NEW ANALYSIS OF THE BAND OF HDCO (MONODEUTERATED FORMALDEHYDE) IN THE 5.8 m REGION L. GOMEZ, LAboratoire de Dynamique, Interactions et R éactivité (LADIR, CNRS UMR 7075) Université Pierre et Marie Curie - Paris VI ; Case courrier 49, B ât F 74, 4, place Jussieu, 75252 Paris Cedex, France.; A.PERRIN, Laboratoire Inter Universitaire des Systemes Atmosph ériques, CNRS, Université Paris 12, 61 Av du General de Gaulle, 94010 Cr éteil Cedex France; G. C. MELLAU, Justus-Liebig - Universit ät, PhysikalischChemisches Institut, Heinrich-Buff-Ring 58, D-35392 Gießen, Germany. Using high-resolution Fourier transform spectra of mono deuterated formaldehyde (HDCO) recorded in the 5.8 m spectral range at Giessen (Germany), we carried out an extensive analysis of the strong fundamental band (carbonyl stretching mode) at 1724.2676 cm , starting from results of a previous analysis a . For this hybrid band (with both - and -type transitions) the analysis was pursued up to high rotational quantum numbers. In this way, it was possible to evidence resonances which perturb the lines which are due to the existence of the 2 (at 2059 cm ) and + (at 2087 cm ) dark bands b . In addition a local resonance is perturbing the 3 levels which is due to a crossing with the 4 energy levels. However the 4 state is also involved in strong vibration-rotation interactions coupling the 5 ,6 ,4 system of resonating states of HDCO c . Therefore the final energy levels calculation which was performed for the 5 ,6 ,4 ,3 ,5 ,5 6 resonating states accounts for the observed - type, - type -type Coriolis (and/or) Fermi resonances. In this way it was possible to reproduce the observed line positions, within their experimental uncertainties. Finally using a band intensity available in the literature d we generated, for the first time, a list of line parameters (positions and intensities) for the 5.8 m band of HDCO. a Johns b , JWC, McKellar ARW., J Mol Spectrosc 1977; 64: 327-339 and correspond to the CHD bending (at 1396 cm ), the CHD rocking (at 1028 cm ) and the CHD out of plane (at 1059 cm ) modes, respectively c A. Perrin, J. M. Flaud, L. Margulès, J. Demaison, H. Mäder and S. Wörmke, J. Mol. Spectrosc. 216, 214 (2002) d Gratien, Nilsson, Doussin, Johnson, Nielsen, Stenstrom and Picquet-Varrault, J. Phys. Chem. 111, 11506 (2007) Intermission 264 RI08 HARMONISATION OF GOME, SCIAMACHY AND GOME-2 OZONE CROSS-SECTIONS 15 min 3:45 ANNA SERDYUCHENKO, JOHN P. BURROWS and MARK WEBER, Institut für Umweltphysik, Universität Bremen, Ott-Hahn-Allee 1, D-28359 Bremen, Germany. The generation of long-term datasets of atmospheric trace gases is a major need and prerequisite for climate and air quality related studies. In particular ozone is an important species in the stratosphere (UV protection) and troposphere (air pollution, climate gas). The global monitoring capabilities of satellite borne atmospheric chemistry sensors play a unique role in the determination of long term trends. Currently there are three atmospheric chemistry instruments with a high potential of synergy in orbit: the Global Ozone Measuring Experiment (GOME), the Scanning Imaging Absorption Spectrometer for Atmospheric Chartography (SCIAMACHY), and GOME-2. Two more satellites, each carrying a GOME-2 spectrometer are planned to be launched five years apart in the next decade. It will result in a time series covering two or more decades of ozone observations. As the lifetime of individual satellite missions is limited, information from different sensors needs to be combined. The goal of the current work is to derive a consolidated and consistent set of absorption cross-sections in the UV/visible spectral region for GOME, SCIAMACHY, GOME-2 series that allows the derivation of a harmonized long term data set. The harmonization of cross-sections is carried out by a combination of re-evaluation of the cross-sections measured in laboratory pre-flight with the satellite spectrometers and of new experimental work to improve upon the absolute scaling of the available cross-section data. This work is in progress. Based on the results from the work, it is expected that the ozone data quality and time series will improve significantly as required for climate, air quality, and stratospheric ozone trend studies. As a delivery updated ozone cross-sections will be available for reprocessing with GOME, SCIAMACHY and GOME2 and to the scientific community as well. Work is supported by European Space Agency. RI09 15 min 4:02 HIGH-RESOLUTION SPECTROSCOPY AND ANALYSIS OF THE DYAD OF CF V. BOUDON, Institut Carnot de Bourgogne, UMR 5209 CNRS–Universit é de Bourgogne, 9 Av. A. Savary, BP 47870, F-21078 Dijon Cedex, France; A. DOMANSKAYA, Institute of Physics, St. Petersburg University, 198504 St. Petersburg, Russia; C. MAUL, Institut f ür Physikalische und Theoretische Chemie der Technischen Universität Braunschweig, D-38106 Braunschweig, Germany; R. GEORGES, Institut de Physique de Rennes, UMR 6251 CNRS–Universit de Rennes 1, 263 Av. G énéral Leclerc, F-35042 Rennes Cedex, France; J. MITCHELL, University of Arkansas, 226 Physics Building, Fayetteville AR 72701, USA. CF is a strong greenhouse gas of both anthropogenic and natural origin a . However, high-resolution infrared spectroscopy of this molecule has received only a limited interest up to now. The public databases only contain cross-sections for this species, but no detailed line list. We reinvestigate here the strongly absorbing region around 7.3 m. Two new Fourier transform infrared spectra at a 0.003 cm resolution have been recorded: i) a room-temperature spectrum in a static cell with a 5 mb pressure and ii) a supersonic expansion jet spectrum at a 15 K estimated temperature. Following the work of Gabard et al. b , we perform a simultaneous analysis of both the and bands since a strong Coriolis interaction occurs between them, perturbing the -branch rotational clusters around & . As in Ref. b, we also include microwave data in the fit. The analysis is performed thanks to the XTDS and SPVIEW programs c . Compared to Ref. b, the present work extends the analysis up to higher & values (56 instead of 32). Absorption intensities are estimated thanks to the dipole moment derivative value of D. Papoušek et al. d and compare well with the experiment. The rotational energy surfaces for the dyad are also examined in order to understand the distribution of rovibrational levels. a D. R. Worton, W. T. Sturges, L. K. Gohar et al., Environ. Sci. Technol. 41, 2184–2189 (2007). Gabard, G. Pierre and M. Takami, Mol. Phys. 85, 735–744 (1995). c Ch. Wenger, V. Boudon, M. Rotger, M. Sanzharov and J.-P. Champion, J. Mol. Spectrosc., 251 102–113 (2008). d D. Papoušek, Z. Papoušková and D. P. Chong, J. Phys. Chem. 99, 15387–15395 (1995). b T. 265 RI10 15 min 4:19 NEW HIGH-RESOLUTION ABSORPTION CROSS-SECTION MEASUREMENTS OF HCFC-142B IN THE MID-IR KARINE LE BRIS, Department of Physics, St. Francis Xavier University, Antigonish, NS, Canada, B2G2W5; KIMBERLY STRONG, Department of Physics, University of Toronto, Toronto, ON, Canada, M5S1A7; and STELLA MELO, Canadian Space Agency, St. Hubert, QC, Canada, J3Y8Y9. HCFC-142b (1-chloro-1,1-difluoroethane) is a temporary substitute for ozone-depleting chlorofluorocarbons (CFCs). However, due to its high absorption cross-sections in the mid-IR, HCFC-142b is also a highly potent greenhouse gas, now detectable from space by satellite missions. So far, the accuracy of the retrieval has been limited by the lack of reference data in a range of temperatures compatible with atmospheric observations. We present new absorption cross section measurements of HCFC-142b at high-resolution (0.02 cm ) from 223 K to 283 K in the 600 cm – 4000 cm spectral window. The composite spectra are calculated for each temperature from a set of acquisitions at different pressures by Fourier transform spectroscopy. RI11 LINE INTENSITIES OF ISOTOPIC CARBONYL SULFIDE (OCS) AT 2.5 MICROMETER 15 min 4:36 ROBERT A. TOTH, KEEYOON SUNG, LINDA R. BROWN, TIMOTHY J. CRAWFORD, Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109. We have measured line intensities of O C S, O C S, O C S, O C S, and O C S in the 2.5 m region for the first time to support planetary studies of the Venus atmosphere. Laboratory absorption spectra of OCS were recorded at 0.0033 cm resolution at room temperature using a Bruker IFS 125-HR Fourier transform spectrometer at the Jet Propulsion Laboratory. Normal samples of OCS were used in this study, and sample impurities and isotopic abundances were determined from mass spectrum analysis. Optical densities sufficient to observe isotopic bands and weaker hot bands were achieved by using a multi-pass White cell and single pass gas cells in various path lengths, which were validated by analyzing near-IR CO spectra. We present line intensities for almost 30 bands of the OCS isotopes excluding ground state bands of O C S, which we have reported recently. We have Herman-Wallis factors determined for the individual bands. In some cases, it has been observed that band intensities normalized to 100% isotopic species show a significant deviation from that of the primary isotopic species (up to by 12.5%). No earlier measurements have been reported for these bands. Measurement precision and accuracies will be discussed. a a Research described in this paper was performed at the Jet Propulsion Laboratory, California Institute of Technology, under contracts and cooperative agreements with the National Aeronautics and Space Administration. We thank Drs. Stojan Madzunkov, John A. MacAskill, and Murray R. Darrach from the Atomic and Molecular Collision Group at Jet Propulsion Laboratory for recording mass spectrum of the OCS sample used in this work. 266 RI12 cm 15 min 4:53 THE 4850 SPECTRAL REGION OF CO : CONSTRAINED MULTISPECTRUM NONLINEAR LEAST SQUARES FITTING INCLUDING LINE MIXING, SPEED DEPENDENT LINE PROFILES AND FERMI RESONANCE D. CHRIS BENNER, V. MALATHY DEVI, EMILY NUGENT, Department of Physics, College of William and Mary, Box 8795, Williamsburg, VA 23187-8795; LINDA R. BROWN, CHARLES E. MILLER, ROBERT A. TOTH, and KEEYOON SUNG, Jet Propulsion Laboratory a, California Institute of Technology, Pasadena, CA 91109. Room temperature spectra of carbon dioxide were obtained with the Fourier transform spectrometers at the National Solar Observatory’s McMath-Pierce telescope and at the Jet Propulsion Laboratory. The multispectrum nonlinear least squares fitting technique b is being used to derive accurate spectral line parameters for the strongest CO bands in the 4700-4930 cm spectral region. Positions of the spectral lines were constrained to their quantum mechanical relationships, and the rovibrational constants were derived directly from the fit. Similarly, the intensities of the lines within each of the rovibrational bands were constrained to their quantum mechanical relationships, and the band strength and Herman-Wallis coefficients were derived directly from the fit. These constraints even include a pair of interacting bands with the interaction coefficient derived directly using both the positions and intensities of the spectral lines. Room temperature self and air Lorentz halfwidth and pressure induced line shift coefficients are measured for most lines. Constraints upon the positions improve measurement of pressure-induced shifts, and constraints on the intensities improve the measurement of the Lorentz halfwidths. Line mixing and speed dependent line shapes are also required and characterized. a The research at the Jet Propulsion laboratory (JPL), California Institute of Technology, was performed under contract with National Aeronautics and Space Administration. b D. Chris Benner, C.P. Rinsland, V. Malathy Devi, M.A.H. Smith, and D. Atkins, J. Quant. Spectrosc. Radiat. Transfer 53, 705-721 (1995) RI13 15 min 5:10 MEASUREMENTS OF THE CO 15 m BAND SYSTEM BROADENED BY AIR, N AND CO AT TERRESTRIAL ATMOSPHERIC TEMPERATURES M. A. H. SMITH, Science Directorate, NASA Langley Research Center, Hampton, VA 23681; V. MALATHY DEVI, D. CHRIS BENNER, Department of Physics, The College of William and Mary, Williamsburg, VA 23187; T. A. BLAKE and R. L. SAMS, William R. Wiley Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, WA 99352. In earth remote sensing, retrievals of atmospheric temperature profiles are often based on observed radiances in infrared spectral regions where emission from atmospheric CO predominates. To achieve improved retrieval accuracy, systematic errors in the forward model must be reduced, especially those associated with errors in the spectroscopic line calculation. We have recorded more than 110 new high-resolution infrared spectra of the 15-m band system of CO to accurately determine line intensities, self-, air- and N -broadened widths and pressure-induced line shifts, along with their temperature dependences. The spectra were recorded with the Bruker IFS 120 HR Fourier transform spectrometer at Pacific Northwest National Laboratory (PNNL) and temperature-controlled sample cells. Sample temperatures were between 206K and 298K. Maximum total pressures were 15 Torr for self-broadening and 613 Torr for air- and N -broadening. Analysis is done using a multispectrum fitting technique a to retrieve the spectroscopic parameters. Line mixing and other non-Lorentz, non-Voigt line shapes are also assessed. The resulting line parameters are compared with the HITRAN database b and with other measurements. a D. Chris Benner, C.P. Rinsland, V. Malathy Devi, M.A.H. Smith, and D. Atkins, J. Quant. Spectrosc. Radiat. Transfer 53, 705-721 (1995) Rothman et al., J. Quant. Spectrosc. Radiat. Transfer 96, 139-204 (2005); L.S. Rothman et al., J. Quant. Spectrosc. Radiat. Transfer, in press b L.S. (2009) 267 RI14 15 min 5:27 LINE POSITIONS, INTENSITIES, SELF- AND N -BROADENING PARAMETERS IN THE BAND OF ETHANE (C H ) CURTIS P. RINSLAND, Science Directorate, NASA Langley Research Center, Hampton, VA 23681; V. MALATHY DEVI, D. CHRIS BENNER, Department of Physics, The College of William and Mary, Williamsburg, VA 23187; ROBERT L. SAMS and THOMAS A. BLAKE, William R. Wiley Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, WA 99352. High-resolution infrared spectra of ethane have been recorded using the Bruker IFS 120 HR Fourier transform spectrometer (FTS) at the Pacific Northwest National Laboratory (PNNL), in Richland, Washington. Several spectra of pure ethane and ethane in N mixtures were obtained with absorption paths of 20 cm and 3.2 m. Room temperature spectra were obtained in both 20 cm and 3.2 m paths while cold spectra were obtained using only the 20 cm path cell. The spectra were obtained at 0.0028 cm resolution with sample pressures ranging from 0.3 to 36 torr for pure ethane and 11 to 180 torr in ethane-N mixtures. The volume mixing ratios of ethane in the ethane-N mixtures varied between 0.01 and 0.2. The gas temperatures varied from -66 Æ C to 24Æ C. Positions, intensities, self- and N -broadening parameters were determined by processing 16 or 17 room temperature spectra using the multispectrum nonlinear least squares spectrum fitting technique a. The results obtained for transitions in a few select Q and & Q sub-bands will be reported at this time. a D. Chris Benner, C.P. Rinsland, V. Malathy Devi, M.A.H. Smith, and D. Atkins, J. Quant. Spectrosc. Radiat. Transfer 53, 705-721 (1995) 268 RJ. THEORY THURSDAY, JUNE 25, 2009 – 1:30 PM Room: 2015 McPHERSON LAB Chair: RUSSELL PITZER, The Ohio State University, Columbus, Ohio RJ01 INVITED TALK 30 min 1:30 THE CALCULATION OF ROTATIONAL ENERGY LEVELS USING TUNNELING HAMILTONIANS JON T. HOUGEN, Optical Technology Division, NIST, Gaithersburg, MD 20899-8441. The present talk will present a pedagogical introduction and review of 25 years of using tunneling Hamiltonians to parameterize and fit rotationally resolved spectra of small polyatomic molecules with one or more large-amplitude motions (LAMs). This tunneling formalism does not require a quantitative knowledge of the potential surface, but instead makes use only of its symmetry properties. Topics planned for discussion include: the user communities for such Hamiltonians; the range of applicability and achievable accuracy; a representative list of molecules treated to date and their various combinations of internal-rotation, inversion, hydrogen-bond-exchange, and H-atom-transfer LAMs; a way of organizing the LAMs of these molecules in the mind using the piston-and-crankshaft vocabulary of the reciprocating engine; how the theoretical tools of point-groups, permutation-inversion groups, extended groups, and time reversal are used in the tunneling-Hamiltonian formalism; and finally a brief report on the present status of two unfinished applications of the tunneling-Hamiltonian formalism, namely cis/trans bent acetylene (HCCH) and protonated acetylene (C H ). RJ02 15 min 2:05 LINE SHIFTS IN ROTATIONAL SPECTRA OF POLYATOMIC CHIRAL MOLECULES CAUSED BY THE PARITY VIOLATING ELECTROWEAK INTERACTION J. STOHNER, ZHAW Zürich University for Applied Sciences, ICBC, Reidbach T, CH 8820 W ädenswil, Switzerland, sthj@zhaw.ch.; M. QUACK, ETH Z ürich, Physical Chemistry, CH 8093 Z ürich, Switzerland. Are findings in high-energy physics of any importance in molecular spectroscopy ? The answer is clearly ‘yes’. Energies of enantiomers were considered as exactly equal in an achiral environment, e.g. the gas phase. Today, however, it is well known that this is not valid. The violation of mirror-image symmetry (suggested theoretically and confirmed experimentally in 1956/57) a was established in the field of nuclear, high-energy, and atomic physics since then, and it is also the cause for a non-zero energy difference between enantiomers. We expect today that the violation of mirror-image symmetry (parity violation) influences chemistry of chiral molecules as well as their spectroscopy. b Progress has been made in the quantitative theoretical prediction of possible spectroscopic signatures of molecular parity violation. The experimental confirmation of parity violation in chiral molecules is, however, still open. Theoretical studies are helpful for the planning and important for a detailed analysis of rovibrational and tunneling spectra of chiral molecules. We report results on frequency shifts in rotational, vibrational and tunneling spectra of some selected chiral molecules which are studied in our group. c If time permits, we shall also discuss critically some recent claims of experimental observations of molecular parity violation in condensed phase systems. d a T. D. Lee, C. N. Yang, Phys. Rev., 104, 254 (1956); C. S. Wu, E. Ambler, R. W. Hayward, D. D. Hoppes, R. P. Hudson, Phys. Rev., 105, 1413 (1957) Quack, Angew. Chem. Intl. Ed., 28, 571 (1989); Angew. Chem. Intl. Ed., 41, 4618 (2002); M. Quack, J. Stohner, Chimia, 59, 530 (2005); M. Quack, J. Stohner, M. Willeke, Ann Rev. Phys. Chem. 59, 741 (2008) c M. Quack, J. Stohner, Phys. Rev. Lett., 84, 3807 (2000); M. Quack, J. Stohner, J. Chem. Phys., 119, 11228 (2003); J. Stohner, Int. J. Mass Spectrometry 233, 385 (2004); M. Gottselig, M. Quack, J. Stohner, M. Willeke, Int. J. Mass Spectrometry 233, 373 (2004); R. Berger, G. Laubender, M. Quack, A. Sieben, J. Stohner, M. Willeke, Angew. Chem. Intl. Ed., 44, 3623 (2005) d J. Stohner, M. Quack, to be published b M. 269 RJ03 USING DIFFUSION MONTE CARLO TO PROBE ROTATIONAL EXCITED STATES 15 min 2:22 ANDREW S. PETIT and ANNE B. McCOY, Department of Chemistry, The Ohio State University, Columbus, OH 43210. Since its inception in 1975 by Anderson, a Diffusion Monte Carlo (DMC) has been successfully applied to a wide range of electronic and vibrational problems. In the latter case, it has been shown to be a powerful method for studying highly fluxional systems exhibiting large amplitude vibrational motions. We report here our recent work developing a new DMC algorithm capable of treating rotational excited states. We first develop the appropriate coordinates, nodal structures, and re-crossing corrections for this problem. Then, using H O and D O as model systems,b we show that our method can successfully describe a range of rotational states from to . In particular, we examine the combined effects of rotational and zero-point vibrational motion on the geometric structure of the molecules. Finally, we find the state to be somewhat problematic but show that the problem is straightforward to identify and has a well-defined solution. a J. B. Anderson, J. Chem. Phys., 63, 1499 (1975). Huang, S. Carter, and J. Bowman, J. Chem. Phys., 118, 5431 (2003). b X. RJ04 15 min 2:39 PROBING ROTATIONALLY EXCITED STATES OF CH WITH DIFFUSION MONTE CARLO CHARLOTTE E. HINKLE, ANNE B. McCOY, Department of Chemistry, The Ohio State University, Columbus, OH 43210. Protonated methane has long proven to be a challenging system for both experimentalists and theoreticians. The essentially flat potential surface comprised of 120 equivalent minima, coupled with a very fluxional molecule, make CH a challenging system to study. Using Diffusion Monte Carlo we have had previous success studying vibrationally excited states of CH . Here we focus on modeling rotationally excited states using Diffusion Monte Carlo. Following our success with H O and D O we define our rotationally excited states by placing nodes at the zeros in the real rotational eigenstates of a symmetric top. We use this approach to analyze rotationally excited states of CH through use of Fixed Node Diffusion Monte Carlo. We use the results of these simulations to analyze the rotation vibration mixing in rotationally excited states of CH . 270 RJ05 15 min 2:56 ENERGY-LEVEL-CLUSTER RELATED NUCLEAR-SPIN EFFECTS AND SUPER-HYPERFINE SPECTRAL PATTERNS: HOW MOLECULES DO SELF-NMR WILLIAM HARTER, JUSTIN MITCHELL, University of Arkansas, Department of Physics, Fayetteville, AR 72701. At several points in his defining works on molecular spectroscopy, Herzberg notes that “because nuclear moments . . . are so very slight . . . transitions between species . . . are very strictly forbidden. . . ” Herzbergs most recent statement of such selection rules pertained to spherical top spin-species a . It has since been shown that spherical top species (as well as those of lower symmetry molecules) converge exponentially with momentum quanta & and ' to degenerate level clusters wherein even “very slight” nuclear fields and moments cause pervasive resonance and total spin species mixing b . Ultra-high resolution spectra of Borde, et .al c and Pfister et .alde shows how SF and SiF Fluorine nuclear spin levels rearrange from total-spin multiplets to NMR-like patterns as their superfine structure converges. Similar super-hyperfine effects are anticipated for lower symmetry molecules exhibiting converging superfine levelclusters. Examples include PH moleculesf and asymmetric tops. Following this we consider models that treat nuclear spins as coupled rotors undergoing generalized Hund-case transitions from spin-lab-momentum coupling to various spinrotor correlations. a G. A. Herzberg, Electronic Spectra of Polyatomic Molecules, (Von Norstrand Rheinhold 1966) p. 246. G. Harter and C. W Patterson, Phys. Rev. A 19, 2277 (1979); W. G. Harter, Phys. Rev. A 24, 192 (1981). c Ch. J. Borde, J. Borde, Ch. Breant, Ch. Chardonnet, A. Van Lerberghe, and Ch. Salomon, in Laser Spectroscopy VII, T. W Hensch and Y. R. Shen, eds. (Springer-Verlag, Berlin, 1985). d O. Pfister, F. Guernet, G. Charton, Ch. Chardonnet, F. Herlemont, and J. Legrand, J. Opt. Soc. Am. B 10, 1521 (1993). e O. Pfister, Ch. Chardonnet, and Ch. J. Bord, Phys. Rev. Lett. 76, 4516 (1996). f S. N. Yurchenko, W. Thiel, S. Patchkovskii, and P. Jensen, Phys. Chem. Chem. Phys.7, 573 (2005). bW RJ06 15 min 3:13 ROVIBRATIONAL PHASE-SPACE SURFACES FOR ANALYSIS OF POLYAD BAND OF CF JUSTIN MITCHELL, WILLIAM HARTER, University of Arkansas, Department of Physics, Fayetteville, AR 72701; VINCENT BOUDON, Institut Carnot de Bourgogne, UMR 5209 CNRS–Universit é de Bourgogne, 9 Av. A. Savary, BP 47870, F-21078 Dijon Cedex, France. Even after nearly a century of scientific effort, the spectra of spherical top molecules, such as methane, are notoriously problematic to evaluate both experimentally and theoretically. These are molecules that show complex interactions, strongly coupling rotations to vibrations, if not electronics. Theoretical and computational tools exist a to predict these spectra, but they could be greatly aided by Rovibrational Phase-Space analysis, such as the Rotational Energy Surface (RES). Some such analysis exists in the literature b c , but advances in computing hardware and computational tools have made it much easier. This talk will show a more complicated RES analysis than has been done before, evaluating the polyad band of CF . a Ch. Wenger, J.P. Champion, J. Quant. Spect. and Rad. Trans. 59, 471 (1998) Harter, C.W. Patterson and H.W. Gailbraith, J Chem Phys 69, 4896 (1978) c Dhont et al, J Mol Spect, 201, 95 (2000) b W.G. Intermission 271 RJ07 15 min 3:45 THE LOW-LYING STATES OF SF SPECIES ( =1–6): INSIGHTS INTO HYPERVALENCY FROM THE RECOUPLED PAIR BONDING MODEL D. E. WOON and T. H. DUNNING, JR., Department of Chemistry, University of Illinois at UrbanaChampaign, Urbana, IL 61801. High level MRCI and RCCSD(T) calculations with correlation consistent basis sets were used to characterize SF species. By examining both the stable structures and the bonding processes that occur during SF + F SF additions, we have derived a new model for describing hypervalent behavior that we call recoupled pair bonding, in which a pair of electrons on S can be decoupled to allow formation of a bond with F. The new model accounts for the origin of hypervalency, the presence of low-lying excited states, and the structures and spectral properties of neutral and ionic SF species; it has more predictive capability than other models. For example, while SF and SF both have covalently bonded ground states, they each have low-lying excited states with at least one recoupled pair bond. To the best of our knowledge, the SF( ), SF ( ), and SF ( ) states have not yet been observed experimentally. RJ08 15 min 4:02 UNDERSTANDING THE MOLECULAR PROPERTIES OF ClF ( 1-7) SPECIES: AN APPLICATION OF THE RECOUPLED PAIR BONDING MODEL FOR HYPERVALENT BONDS L. CHEN, D. E. WOON, and T. H. DUNNING, Jr., Department of Chemistry, University of Illinois at UrbanaChampaign, Urbana, IL 61801. Recently, new insight into the nature of hypervalent behavior led us to develop a model called recoupled pair bonding. In this model, two hypervalent bonds can be formed by decoupling a valence or electron pair. However, energy must be expended to decouple an electron pair, and the first bond is weakened as a consequence. The recoupled pair bonding model has been proven successful in our initial study of the SF ( 1-7) species. To further examine the applicability of this new model, this study explored the molecular properties of the ClF ( 1-7) series. Optimized ground state structures, bond energies, and spectral properties of these molecules were obtained by employing high level ab initio calculations [MRCI, CCSD(T)] with correlation consistent basis sets. Because of recoupled pair bonding, there are unanticipated low-lying excited states such as ClF ( ) and ClF ( , ). We also systematically explored the bond formation processes, adding F atoms one at a time to the optimized ClF (1 6 ) molecules. We find the bond energies for F addition to form ClF , ClF , and ClF are much lower than those leading to ClF, ClF and ClF . This oscillating trend is analogous to what is seen in the SF species, though the bond energies of the SF species are considerably greater than the ones for ClF . The lower bond energies of the even species in the ClF series reflects the cost of decoupling paired electrons of the central atom, and the difference between ClF and SF reflects the fact that more energy is needed to decouple each of the pairs of electrons of Cl than the single pair of S. This behavior and other trends observed in ClF species demonstrate the improved predictive ability of the recoupled pair bonding model over other models for describing hypervalent bonding. 272 RJ09 15 min 4:19 CALCULATION OF GAS-PHASE ELECTRONIC SPECTRA OF TRANSITION-METAL COMPLEXES a JAMES T. MUCKERMAN, Chemistry Department, Brookhaven National Laboratory, Upton, NY 119735000. Despite widespread interest in the electronic structure and spectra of transition-metal complexes such as the starting and intermediate species of redox catalysts for water oxidation or hydrogen production, theoretical predictions of their electronic spectra generally come only from time-dependent density functional theory (TD-DFT) and are limited to one-electron excitations. Here we compare the results of TD-DFT to those of multi-reference configuration-interaction calculations for predicting the electronic spectra of some model and actual transition-metal-containing catalysts. Of particular interest are complexes with redox-active ligands that complicate the assignment of formal oxidation states, and complexes containing second- and third-transition-series metals. a This work was performed at Brookhaven National Laboratory and funded under contract DE-AC02-98CH10886 with the U.S. Department of Energy and supported by its Division of Chemical Sciences, Geosciences, and Biosciences, Office of Basic Energy Sciences. The U.S Department of Energy is also gratefully acknowledged for funding under the BES Hydrogen Fuel Initiative. RJ10 15 min 4:36 BALANCED DESCRIPTION OF GROUND-STATE PROPERTIES, VALENCE EXCITATIONS, AND CHARGETRANSFER EXCITATIONS WITH LONG-RANGE CORRECTED DENSITY FUNCTIONALS MARY A. ROHRDANZ, JOHN M. HERBERT, Department of Chemistry, The Ohio State University, Columbus, OH 43210. Time-dependent density functional theory’s favorable scaling properties make it an attractive technique for the study of large, condensed-phase systems. However, in such systems conventional generalized gradient approximation functionals are plagued by spurious, low-energy charge transfer (CT) excitations. Long-range corrected (LRC) functionals, which asymptotically turn on full Hartree-Fock exchange at long range, push these CT states to higher energies. Until recently it has seemed impossible to find a long-range corrected functional that performed acceptably well for both ground- and excited-state properties. We have constructed an implemented a LRC hybrid functional that not only performs reasonably well in a battery of tests on ground-state properties and valence excitations, but also achieves reasonable accuracy for a small database of CT excitations. RJ11 AB INITIO POTENTIAL ENERGY SURFACE FOR THE Xe+OH INTERACTION 15 min 4:53 VIPIN B. SINGH, Department of Physics, U P Autonomous College, Varanasi-221002, India; MICHAEL C. HEAVEN, Emersion Center for Scientific Computation, Emory University, Atlanta GA, USA. Ab initio potential energy surface for the gorund and first excited states of the Xe+OH complex were calculated using the state-averaged complete active space MCSCF (CASSCF) and multi reference Cl methods as implemented in MOLPRO 2006 program. A large one-electron basis consisting of the augmented-correlation consistent polarized valence five zeta (aug-cc-pV5Z) set is used. Interaction energies were obtained as the difference between the energy of the complex and energies of the fragments. We computed the fragments in the same basis set as complex to avoid so called basis set superposition error. The Xenon atom has 54 electrons; the 28 inner shell electrons are described by a relativistic pseudopotential. The interaction energy derived for a T-shaped geometry in the ground state is about 250 cm , which support the earlier reported value obtained by CCSD method. a Interestingly our calculation predicts that in the first excited state this interaction energy increases to 9321 cm for the linear gemoetry of Xe+OH complex. Thus, however in the degenerate ground state interaction is weak, but in the first excited state this (Rare Gas-OH) Van der Waals interaction behaves just like a chemical bond. Comparison with other Rg-OH complexes has been carried out. a J. A. Gilijamse et al. Science, 313, 1617 (2006). 273 RJ12 10 min 5:10 ELECTRONIC STRUCTURE OF PA IONS: LOOKING FOR CLARITY IN ACTINIDE ELECTRONIC STRUCTURE MICHAEL MROZIK, RUSSELL M. PITZER, DEPT. OF CHEMISTRY, THE OHIO STATE UNIVERSITY; BRUCE E. BURSTEN, UNIVERSITY OF TENNESSEE-KNOXVILLE. Since the identification of f-orbital contribution to the bonding in PaO , investigation into Pa cations have hoped to characterize as many of the electronic states possible. Electronic states of the Pa ions have been investigated using multi-reference spin-orbit configuration interaction (H ). Each additional electron in the series adds increased complexity and difficulty in evaluation of electronic states. Comparison of results with data at NIST and its institutional analog in France, or lack there of, indicate that I coupling does not adequately describe all the complexity present in these ions. Instead of I or a 7 -7 coupling we propose that states of the Pa ions would be better described using a & J labeling of states. Gibson 0%=% . 0==9 2007, , 3947-3956. ¯ RJ13 ELECTRONIC STRUCTURE OF N DIMER CATION 10 min 5:22 K. KHISTYAEV, A. I. KRYLOV, AND A. LANDAU, Department of Chemistry, University of Southern California, Los Angeles, CA 90089. Energies of the ground and the lowest excited states of the N dimer cation were calculated. EOM-IP-CCSD method was used for calculations. The goal of this study was to explain experimental data of N dimer dissociation following charge-exchange between nitrogen dimer cation and Cs from R. Continetti group. This system is also very interesting from the theoretical point of view because of the unusual electronic structure and as a model charge-transfer system. We characterized the bonding of the ionized system due to orbital overlaps between the fragments. To extend EOM-IP-CCSD to large systems, frozen natural orbitals approach can be employed. Benchmark results demonstrating the performance of EOM-IP-CCSD/FNO scheme will be presented. We found that for closed shell molecules the orbital space can be reduced by 40% with minor effect on the ionization energy at EOM-IP-CCSD level (the minimal absolute errors are about 1 kcal/mol). 274 FA. THEORY FRIDAY, JUNE 26, 2009 – 8:30 AM Room: 160 MATH ANNEX Chair: VINCENT BOUDON, Université de Bourgogne, Dijon, France FA01 LOCATING MINIMUM ENERGY CROSSING POINTS USING EOM-CC METHODS 15 min 8:30 E. EPIFANOVSKY and A. I. KRYLOV, University of Southern California, Los Angeles, CA 90089. Non-adiabatic and spin-forbidden processes involve transitions between electronic states through potential energy surface (PES) crossings. They are often found in atmospheric and combustion chemistry, photochemistry and photobiology. To describe the kinetics of such processes, a version of transition state theory can be applied. Locating the minimum energy crossing point of the PESs is the first step of characterizing a spin-forbidden reaction. The point corresponds to the transition state of the process. This work presents a computational procedure for minimizing singlet-triplet crossings of PESs, which is applied to a benchmark series of methylene-related radicals, formaldehyde, and oxybenzene, an intermediate in atmospheric formation of phenol. The intersection minimum in the studied methylene-related radicals is located very close to the excited state minimum, singlet for CH and triplet for CHF and CF . The crossing in oxybenzene is found along the CO wagging coordinate. In the case of para-benzyne, which has a singlet-triplet adiabatic excitation energy of less than 0.2 eV, the crossing minimum is unexpectedly located 0.65 eV above the ground state equilibrium energy and corresponds to a distorted ring geometry. FA02 INTRAMOLECULAR CHARGE TRANSFER STATES IN THE CONDENSED PHASE 15 min 8:47 C. F. WILLIAMS and J. M. HERBERT, Ohio State Chemistry Department, Newman and Wolfrom Lab, 100 W. 18th Avenue Columbus, OH, 43210. Time-Dependent Density Functional Theory (TDDFT) with long range corrected functionals a can give accurate results for the energies of electronically excited states involving Intramolecular Charge Transfer (ICT) in large molecules. If this is combined with a Molecular Mechanics (MM) representation of the surrounding solvent this technique can be used to interpret the results of condensed phase UV-Vis Spectroscopy. Often the MM region is represented by a set of point charges, however this means that the solvent cannot repolarize to adapt to the new charge distribution as a result of ICT and so the excitation energies to ICT states are overestimated. To solve this problem an algorithm that interfaces TDDFT with the polarizable force-field AMOEBA is presented; the effect of solvation on charge transfer in species such as 4,4’dimethylaminobenzonitrile (DMABN) is discussed. a M.A. Rohrdanz, K.M. Martins, and J.M. Herbert, J. Chem. Phys. 130 034107 (2008). FA03 FORMATION OF EXCITED H O STATES BY CHARGE TRANSFER FROM Cs 10 min 9:04 STANISLAV A. DOLGIKH, ANNA I. KRYLOV, Department of Chemistry, University of Southern California, Los Angeles, CA 90007. Charge transfer (CT) probability between Cs and H O was studied. In the experiment a Rydberg type H O molecule is formed in electronically excited state after CT from Cs, following by the dissociation to H O+H. However it is not clear which excited state is a precursor of the dissociation. Electronic structure of H O molecule was investigated by ab initio methods. Couplings between initial and target states were calculated, and charge transfer probabilities were estimated. Calculations show that 4s Rydberg state of H O molecule is the most likely state to be populated in the experiment. 275 FA04 RE–OPTIMIZATION OF AN ELECTRON–WATER PSEUDOPOTENTIAL 15 min 9:16 LEIF D. JACOBSON, JOHN M. HERBERT, Department of Chemistry, the Ohio State University, Columbus, OH 43210. In order to assess the role of self-consistent polarization in simulated properties of electron–water clusters and the experimental extrapolation of VEBE (Vertical Electron Binding Energies) to their bulk counterparts we have previously parameterized an electron–water pseudopotential similar to that most commonly used. This potential was shown to perform very well in reproducing VEBE’s of a large database of clusters as well as reproducing relative isomer energies of small clusters as compared to MP2 predictions. However, when applied to study the dynamics of large systems (greater than 20 water molecules) this potential yielded a diffusely bound, interpenetrating, unstructured picture of the hydrated electron, inconsistent with chemical intuition and experimental results predicting a well defined solvation cavity. We re– evaluate assumptions that went into our previous parameterization, in particular the repulsive potential that arises when casting the true many–electron problem into an effective one–electron problem. Cluster and bulk binding energies as well as electronic absorption spectra will be investigated. FA05 STARK EFFECT AND TORSIONAL MOTION INTERACTION IN BIPHENYL 15 min 9:33 L. H. COUDERT, LISA, UMR 7583 CNRS/Universités Paris 12 et 7, 61 Avenue du G énéral de Gaulle, 94010 Créteil Cedex, France; L. F. PACIOS, Unidad de Quı́mica y Bioquı́mica, Departamento de Biotecnologı́a, ETSI Montes, Universidad Politécnica de Madrid, 28040 Madrid, Spain; and J. ORTIGOSO, Instituto de Estructura de la Materia, CSIC, Serrano 121, 28006 Madrid, Spain. Although the interaction of an electric field with molecular motions has been thoroughly investigated in the case of a rigid molecule,a much less results are available for a non-rigid molecule, like the biphenyl molecule, displaying an internal torsional motion strongly coupled to the electric field. The present paper reports an exact calculation of the rotation-torsion energy levels of a biphenyl molecule interacting with an electric field. This molecule, with formula (C H ) , consists of two rings which can rotate about the CC bond, the angle of internal rotation being taken equal to , with $ . This molecule interacts with the electric field through its induced dipole moment, the interaction being described by the -dependent polarizability tensor. The calculation involves computing rotation-torsion energy levels and wavefunctions using the Hamiltonian derived by Merer and Watson b for ethylene-like molecules. The -dependent electric field interaction Hamiltonian is diagonalized using these wavefunctions as a basis set. The number of energy levels thus obtained being very high, Boltzmannian equilibrium is assumed in order to evaluate average values of several operators related to the molecular orientation, the rotational wavefunction, and the torsional wavefunction. In the paper, these average values will be calculated for several temperatures in two cases: (i) assuming a rigid molecule and setting equal to its equilibrium value, approximately 20.2 Æ, and (ii) taking into account the non-rigidity of the molecule and solving the Schrödinger equation as outlined above. The qualitative differences arising in the case of a static electric field and in the case of a fast oscillating circular polarized field will be discussed. The possibility of torsional control of the moleculec will also be investigated. a Friedrich and Herschbach, Phys. Rev. Lett. 74 (1995) 4623. and Watson, J. Mol. Spectrosc. 47 (1973) 499. c Ramakrishna and Seideman, Phys. Rev. Lett. 99 (2007) 103001. b Merer 276 FA06 ETHANE ASYMMETRIC C-H STRETCHING VIBRATIONAL SPECTRA 15 min 9:50 MARIA VILLA, Departamento de Quimica. Universidad Autonoma Metropolitana, Av. San Rafael Atlixco 186, Col Vicentina, Iztapala, Mexico D.F. 09340, MEXICO; MA. LUISA SENENT, Departamento de Astrofisica Molecular e Infrarroja, Instituto de Estructura de la Materia, C.S.I.C., Serrano 113B, Madrid 28006, SPAIN; and DAVID R. HIDALGO, Departamento de Quimica. Universidad Autonoma Metropolitana, Av. San Rafael Atlixco 186, Col Vicentina, Iztapala, Mexico D.F. 09340. In this work we continue studying the ethane vibrational spectra, being considered as a non-rigid molecule. The . internal rotational angle and the symmetric and anti-symmetric CH stretching normal modes will be the variables under study. Using ab-initio calculations a three dimentional potential is obtained, and finally a three dimentional Far-infrared and infrared spectra will be presented. The results obtained will be compared with the ones reported in the literature. Intermission FA07 15 min 10:20 CONFORMATIONAL PROPERTIES, SPECTROSCOPY AND STRUCTURE OF ISATIN-(WATER) CLUSTERS MILIND K. SINGH, D. M. UPADHYA and VIPIN B. SINGH, Department of Physics, U P Autonomous College, Varanasi-221002, India. The structure, stability and vibrational characteristics of Isatin-(Water) clusters with n=1=3 have been investigated using second order Moller-Plesset (MP2) perturbation tehory and Density Functional Theory (with B3LYP) methods employing the basis set 6-31+G(d). The vertical excitation energies for these complexes have been also computed using the timedependent density functional theory. The three stable conformational isomers, each for Isatin-(Water) and Isatin-(Water) clusters were obtained. It is shown that in the most stable isomer of Isatin-(Water) cluster hydrogen bond between amide hydrogen and oxygen of water is found stronger as compared to the H-bond in Indole-(Water) cluster. For a particular position of complexation of water, between the carbonyl oxygen’s, results an unusual increase in the dipole moment due to an electronic charge displacement from the N atom to the C atom of the neighboring carbonyl bond. This causes a large separation between the effective charges forming the dipole. The complexes involving this position of water are expected to show a small charge transfer character. The experimentally observed electronic absorption peaks are reasonably reproduced by the TD-DFT calculations and it is found that the longest wavelength absorption peak of isatin at 406 nm is significantly red shifted after addition of a water molecule. 277 FA08 Post-deadline Abstract 15 min LASER SPECTROSCOPY AND DENSITY FUNCTIONAL STUDY ON NIOBIUM DIMER CATION 10:37 METIN AYDIN, Department of Chemistry, Faculty of Art and Sciences, Ondokuz Mayis University, 55139, Samsun, Turkey; JOHN R. LOMBARDI , Department of Chemistry and Center for Analysis of Structures and Interfaces (CASI), The City College of New York (CCNY), New York, NY10031. Resonant multiphoton fragmentation spectra of niobium dimer cation (Nb2+) have been obtained by utilizing laser vaporization of a Nb metal target. Ions are mass-selected with a time-of-flight mass spectrometer followed by a mass gate, then fragmented with a pulsed dye laser, and the resulting fragment ions are detected with a second time-of-flight reflectron mass spectrometer and multichannel plate. Photon resonances are detected by monitoring ion current as a function of fragmentation laser wavelength. A rich, but complex spectrum of the cation is obtained. The bands display a characteristic multiplet structure that may be interpreted as due to transitions from the ground state X (,g) to several excited states, X (,u) and X ( ,u). The ground state X (,g) is derived from the electron configuration ($ ) (1! ) (2! ) (Æ ) . The two spin-orbit components are split by 145 cm due to a strong second-order isoconfigurational spin-orbit interaction with the low-lying (,g) state. The vibrational frequencies of the ground sate and the excited state of Nb2+ are identified as well as molecular spin-orbit constants (A # ) in the excited state. The electronic structure of niobium dimer cation was investigated using density functional theory. For the electronic ground state, the predicted spectroscopic properties were in good agreement with experiment. Calculations on excited states reveal congested manifolds of quartet and doublet electronic states in the range 0-30,000 cm , reflecting the multitude of possible electronic promotions among the 4d- and 5s-based molecular orbitals. Comparisons are drawn between Nb and the prevalent isoelectronic molecules V /NbV /Nb /V /NbV.a a M. Aydin and John R. Lombardi J. Phys. Chem. A. xx XXXX 2009. FA09 Post-deadline Abstract SILYL FLUORIDE: LAMB-DIP SPECTRA AND EQUILIBRIUM STRUCTURE 15 min 10:54 CRISTINA PUZZARINI, GABRIELE CAZZOLI, Dipartimento di Chimica ”G. Ciamician”, Universit à di Bologna, I-40126 Bologna, Italy; J ÜRGEN GAUSS, Institut für Physikalische Chemie, Universität Mainz, D-55099 Mainz, Germany. Different isotopic species of sylil fluoride, namely SiH F, SiH F, and SiH F, have been investigated by means of rotational spectroscopy. In particular, the Lamb-dip technique has been employed for resolving the hyperfine structure (hfs) of rotational lines, which is mostly due to the fluorine nucleus. The high resolution of such a technique allowed us to obtain the hyperfine parameters to a very good accuracy. The experimental determination has been strongly supported by highly accurate quantum-chemical calculations of the hyperfine parameters involved (spin-rotation constants as well as direct spin-spin interaction constants), providing reliable values for those parameters experimentally non-determinable. Furthermore, the combination of experimental ground-state rotational constants for different isotopic species with the corresponding calculated vibrational corrections has been considered to determine the equilibrium structure. This evaluation has been supplemented by pure ab initio determinations. More precisely, taking the coupled-cluster singles and doubles (CCSD) level augmented by a perturbative treatment of triple excitations (CCSD(T)) as starting point, extrapolation techniques as well as the inclusion of minor contributions, such as core-correlation effects and higher-excitation, have been considered for obtaining highly accurate results. 278 FA10 Post-deadline Abstract 15 min 11:11 INVESTIGATION OF COUPLING BETWEEN OH STRETCHING AND H O OUT-OF-PLANE BENDING MODES IN OH-H O PESIA SOLOVEICHIK, BRIDGET A. O’DONNELL, MARSHA I. LESTER, Department of Chemistry, University of Pennsylvania, Philadelphia, PA 19104; ANNE B. McCOY, Department of Chemistry, The Ohio State University, Columbus, OH 43210. Hydroxyl radicals (OH) are expected to form strong hydrogen bonds with water (H O); such interactions are found in the gaseous environment of the atmosphere, the interface of liquid water and ice, and bulk regions of liquid water, snow, and ice. The study of binary OH-H O complexes will provide insight on the larger OH-H O complexes found in the aforementioned systems. In this study, a two-dimensional potential of both the A and A binary OH-H O complex, taking both the OH stretching and H O out-of-plane bending modes into account, is constructed using density functional theory with the aug-cc-pVTZ basis. Energies and wave functions of the bound states are generated using a discrete variable representation. These two-dimensional potentials are relevant to the discussion of past experimental microwave studies and the infrared spectrum observed in this laboratory, and are significant in the directing of future experiments. FA11 Post-deadline Abstract 15 min 11:28 STUDYING THE STEREOCHEMISTRY OF NAPROXEN USING ROTATIONALLY RESOLVED ELECTRONIC SPECTROSCOPY. a JUSTIN W. YOUNG, LEONARDO ALVAREZ-VALTIERRA, and DAVID W. PRATT, Department of Chemistry, University of Pittsburgh, PA 15260. Many biochemical processes are stereospecific. An example is the physiological response to a drug that depends on its enantiomeric form. Naproxen is a drug which shows this stereo-specific physiological response. To better understand the stereo specificity of chiral substances, we observed the S S transitions of R- and S-naproxen in the gas phase using rotationally resolved electronic spectroscopy. The results will be discussed. a Work supported by NSF (CHE-0615755) 279 FB. DYNAMICS FRIDAY, JUNE 26, 2009 – 8:30 AM Room: 170 MATH ANNEX Chair: JINGSONG ZHANG, University of California, Riverside, California FB01 QUANTUM SOLVATION OF CO BY H ATOMS: FROM ONSET TO NANODROPLET 15 min 8:30 HUI LI, PIERRE-NICHOLAS ROY and ROBERT J. LE ROY, Guelph-Waterloo Centre for Graduate Work in Chemistry and Biochemistry, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada. Spectroscopic studies of molecules embedded in helium droplets provide a unique opportunity to investigate a superfluid. High-resolution infrared spectra of CO -(He) clusters ranging in size from ‘small’ ( ) to ‘intermediate’ ( ) have been reported recently by McKellar and co-workers. a However, they have not yet been able to extend this range to clusters large enough that the observed vibrational band origins shifts and rotational constants and approached the nanodroplet limit values. b This paper describes the use of modeling techniques to explore the domain between intermediate and ‘larger’ ( ) clusters, seeking to characterize the onset of nanodroplet behaviour. Path integral Monte Carlo (PIMC) simulations using the worm algorithm can in principle provide reliable quantitative results for “larger” clusters approaching the nanodroplet limit. We have recently determined a three-dimensional analytical ‘Morse/Long-Range’ potential energy surface for CO -He, which explicitly depends on the + asymmetric-stretch vibrational motion of CO , and takes account of change in the average value of + when is excited.c d Using this potential, predicted vibrational frequency shifts have been found to be in excellent agreement with experiment across the range , so it is expected to provides a good description of larger clusters. This paper describes results obtained on using this potential in PIMC simulations to predict the effective rotational constant and the band-origin shift for CO in (He) clusters with 8 . The importance of identical-particle exchange effects will be examined by comparing results obtained using both Boltzmann and Bose-Einstein statistics. a J. Tang, A.R.W. McKellar, F. Mezzacapo and S. Moroni Phys. Rev. Lett. 92, 145503 (2004); A.R.W. McKellar, J. Chem. Phys. 128, 044308 (2008). K. Nauta and R.E. Miller, J. Chem. Phys. 115, 10254 (2001); R. Lehnig and W. Jäger, Chem. Phys. Lett. 424, 146 (2006). c H. Li and R.J. Le Roy, J. Chem. Chem. Phys. 10, 4128 (2008). d H. Li, N. Blinov, P.-N. Roy and R.J. Le Roy, J. Chem. Phys. (2009, in press). b FB02 ULTRAFAST HYDROGEN TRANSFER IN N,N-DIMETHYLISOPROPYL AMINE CLUSTERS 15 min 8:47 SANGHAMITRA DEB, MICHAEL P. MINITTI, PETER M. WEBER, Department of Chemistry, Brown University, Providence, Rhode Island 02912. In molecular beams, the tertiary amine N,N-dimethylisopropyl amine (DMIPA) can form clusters that are evident in photoelectron and mass spectra obtained upon resonant multiphoton ionization via the 3p or 3s Rydberg states. By delaying the excitation pulse from the ionization pulse we can time resolve the ultrafast dynamics of the 3p to 3s internal conversion. The mass peaks of the parents and fragments mirror this relaxation. In addition, we observe an unusual time dependence of a protonated parent species, which we interpret as the signature of an ultrafast proton or hydrogen transfer from one parent molecule to the N-atom of its partner in the dimer cluster. The cluster ion fragments after the reaction. DFT calculations of the cluster structure support a proton or H-transfer between tightly bonded cluster components. 280 FB03 DYNAMICS OF VIBRATIONALLY EXCITED PHENOL-CO 15 min 9:04 AMANDA S. CASE, Y. HEIDI YOON, F. FLEMING CRIM, The University of Wisconsin - Madison Department of Chemistry, 1101 University Avenue, Madison, WI 53705. The dynamics of vibrationally excited complexes can be very intriguing, particularly the inefficient energy transfer and nonstatistical predissociation caused by the mismatch in frequencies of inter- and intra-molecular vibrational modes. We are looking at such dynamics in the one-to-one complex of phenol with carbon monoxide. These complexes are weakly bound by about 660 cm in a planar minimum consisting of a nearly linear hydrogen bond between the phenolic hydrogen and the carbon end of the CO moiety. Both dissociation products (phenol and CO) can be conveniently probed with REMPI. We are taking advantage of this to study the dynamics of vibrationally excited phenol-CO. Looking beyond energy transfer and vibrational predissociation, it would be interesting to study both the one-photon and vibrationally mediated photodissociation dynamics of hydrogen production in this complex. Such studies could provide information on the effect the CO has on the dissociation of phenol, emphasizing its influence at the conical intersections. FB04 15 min 9:21 NATURE OF TORSION-INVERSION COUPLING IN CH NH , CH OH AND CH CH RAM S BHATTA, AMY GAO AND DAVID S PERRY, Department of Chemistry, The University of Akron, OH 44325-3601. Two-dimensional torsion-inversion surfaces for methylamine, protonated methanol and ethyl radical were calculated and fit to a function containing a polynomial in the inversion angle(B ) and trigonometric functions of the torsional angle(). Calculations were done at the B3LYP, MP2, and CCSD(T) levels with the 6-311++G(d,p) and 6-311++G(3df, 2p) basis sets and partial optimization. CH NH , CH OH and CH CH have G symmetry with 6-equivalent minima which are located by the various calculations at inversion angles 6.5 to 11; 42 to 45.5 and 52.5 to 55 degrees respectively on either side of planar. The three molecules have very different barriers to inversion ranging from no barrier for CH CH to 838 for CH NH . The dominant torsion-inversion coupling term in all cases has the form cm for CH OH to 1837 cm B. Intermission FB05 15 min 10:00 ENERGY AND RATE DETERMINATIONS TO ACTIVATE THE C-C ! -BOND OF ACETONE BY GASEOUS VANESSA A. CASTLEBERRY, S. JASON DEE, OTSMAR J. VILLARROEL, IVANNA E. LABOREN, SARAH E. FREY and DARRIN J. BELLERT, Department of Chemistry and Biochemistry, Baylor University, Waco, Texas, 76798. A unique application of a custom fabricated photodissociation spectrometer permits the determination of thermodynamic properties (activation energies), reaction rates, and mechanistic details of bare metal cation mediated C-C ! -bond activation in the gas phase. Specifically, the products and rates resulting from the unimolecular decomposition of the Ni Acetone (Ni Ac) adduct are monitored after absorption of a known amount of energy. The three dissociative products which are observed in high yield are Ni , Ni CO, and CH3CO . The latter two fragment ions result from the activation of a C-C !-bond. It was found that minimally 14 000 cm of energy must be deposited into the adduct ion to induce C-C bond breakage. Preliminary results for the Ni activation of the C-C ! -bond of acetone indicate that there are (at least) two low energy reaction coordinates leading to C-C bond breakage. The lower energy pathway emerges from the doublet ground state with an upper limit to the activation energy of 14 000 cm and reaction rate 0.14 molecules/s. The higher energy path is assumed to be along the quartet reaction coordinate with a minimum activation energy of 18 800 cm (relative to the ground state) and a slightly slower reaction rate. 281 FB06 BROADENING THE HORIZONS OF NONLINEAR OPTICS BY NOSE 15 min 10:17 NATHAN J. BEGUE and GARTH J. SIMPSON, Department of Chemistry, Purdue University, Lafayette, Indiana 47907.. Second harmonic generation (SHG) and has developed into powerful a tool for characterizing oriented thin films, surfaces, and interfaces. Furthermore, the nonlinear optical nature of the wave-mixing processes typically results in the generation of coherent exigent light with a well-defined polarization state. This coherence offers unique opportunities for extraction of detailed molecular and surface properties from polarization analysis. In previous studies, nonlinear optical ellipsometry (NOE) has been developed as a means to retain sign and phase information between the different nonzero , tensor elements present in a given sample. However, those previous methods and related approaches for polarization analysis have all relied on the physical movement of optical elements in order to perform the analysis. The time required to physically move the appropriate optical elements ultimately dictates the fastest analysis time possible in a given technique. Such long acquisition times have limited NOE analysis to systems exhibiting excellent photostability. Development of Nonlinear Optical Stokes Ellipsometry (NOSE) has alleviated many of these problems. By increasing the repetition rate of the laser system and replacing previously slow rotating polarization optics with a rapid photoelastic modulator the acquisition time with full polarization analysis has been reduced from several hours to less than a second. This more than four order of magnitude reduction in acquisition time is accompanied by an order of magnitude more precision in , tensors than previously achieved. These improvements have enabled imaging with full ellipsometric analysis at each pixel, allowing a unique contrast mechanism based on principle component analysis of the polarization dependent signal. Additionally insight into crystal quality and orientation of chiral crystals is available. FB07 10 min 10:34 FLUORESCENCE IMAGING: A VERSATILE METHOD TO STUDY PHOTODISSOCIATION DYNAMICS K. M. CHEN, K. C. CHEN, Department of Chemistry, National Sun Yat-sen University, Kaohsiung, Taiwan, Republic of China. To reduce the image blurring which originates from contributions of a cylindrical array of photolysis events in a photodissociation experiment, a variant of fluorescence imaging techniques has been developed to study photodissociation dynamics and collisional relaxation processes in the bulk. The experimental arrangement utilizes sliced imaging techniques of photofragments by the laser-induced fluorescence detection scheme. An unconventional procedure is employed to guide the photolysis laser in the viewing direction of the imaging detector with a proper obstruction. The perpendicularly sliced image is equivalent to a two-dimensional projection of the fluorescence image of photofragments from a single photolysis center. Experimental images of the ICN photodissociation and the collisional relaxation of CN photofragments are presented to illustrate the versatility of the present method. FB08 Post-deadline Abstract 15 min 10:46 SPECTROSCOPIC STRUCTURAL INVESTIGATIONS OF CHARGE-TRANSFER COMPLEXES OF n-DONORS AND SIGMA- AND PI-ACCEPTORS EL-METWALLY NOUR, SIHAM Y. ALQARADAWI, Department of Chemistry and Earth Sciences, Qatar University, P.O.Box 2713 Doha, Qatar. Molecular charge transfer complexes of n-electron donors such as amines, pyridines and polynitrogen cyclic bases with both sigma- and pi-acceptors have been studied spectrophotometrically in chloroform. The reaction stoichiometries were determined using photometric titration methods. The formed CT-complexes are characterized and formulated based on electronic and infrared spectra as well as elemental and thermal measurements. 282 FB09 Post-deadline Abstract DIRECT INFRARED ABSORPTION SPECTROSCOPY OF BENZENE CLUSTERS 15 min 11:03 VIJAYANAND CHANDRASEKARAN, Institut de Physique de Rennes, Equipe Astrochimie Exprimentale,Bat.11C, Campus de Beaulieu, Universit de Rennes1, 35042 Rennes Cedex, France; L.BIENNIER, Institut de Physique de Rennes, Equipe Astrochimie Exprimentale,Bat.11C, Campus de Beaulieu, Universit de Rennes1, 35042 Rennes Cedex, France; R.GEORGES, Institut de Physique de Rennes, Equipe Astrochimie Exprimentale,Bat.11C, Campus de Beaulieu, Universit de Rennes1, 35042 Rennes Cedex, France; E.ARUNAN, Department of Inorganic and Physical Chemistry, Indian Institute of Science,Bangalore, India; K.P.J.REDDY, Department of Aerospace Engineering, Indian Institute of Science,Bangalore, India. In order to find out the global minimum structure of the benzene dimer we engaged in a series of low (0.5 cm-1) and high (0.015 cm-1) resolution direct absorption infrared measurements of benzene clusters in the 3.3 micron region of the fundamental C-H stretch. The benzene clusters are produced in a continuous supersonic expansion generated by a 24-cm long slit nozzle using helium, argon or neon as carrier gases a . Low resolution spectra show a red shift in the CH stretch spectral region which is found to increase with increase in cluster size. When using argon, high resolution spectrum reveals new weak absorption lines between the strongest monomer lines, attributed to the Ar-Benzene complexe. Currently we are involved in recording the high resolution spectrum of the benzene dimer using helium as a carrier gas. a R. FB10 Georges, A. Bonnamy, M Decroi and J Boissoles Molecular Physics 100,1551, (2002) Post-deadline Abstract 15 min 11:20 CALCULATED DEPENDENCE OF VIBRATIONAL BAND FREQUENCIES OF SINGLE-WALLED CARBON NANOTUBES ON DIAMETER METIN AYDIN, Department of Chemistry, faculty of Art and Sciences, Ondokuz Mayis University, 55139, Samsun, Turkey; DANIEL L. AKINS, Center for Analysis of Structures and Interfaces (CASI) Department of Chemistry The City College of The City University of New York New York, New York 10031. We have used density functional theory (DFT) at the B3LYP/6-31G level to calculate Raman and IR spectra of the fourteen zigzag (n, 0) single-walled carbon nanotubes (SWCNTs) and (n, 0)&(2n, 0) double walled carbon nanotube (DWCNTs) that have n ranging from 6 to 19 for SWCNTS, n = 6 to 8 for DWCNTs. In the low frequency RBM region, calculated Raman spectra of SWCNTs indicated that there are three vibrational modes, of symmetries A . , E . and E . , whose frequencies depend strongly on nanotube diameter. The E . g mode is not only diameter dependent, but also the even and odd number hexagon formed in the circumference direction of the CNTs. There are also two IR spectral modes (of A2u and E1u symmetries) found in calculated IR spectra with strong diameter dependencies. We have also found three Raman bands with E . , A . and E . symmetries to exist in the G-band region. For this latter case, computed spectra indicated that while Raman bands with A1g symmetry essentially remain constant for the even number hexagon formed in the circumference direction ((0, 2n)-type CNTs; with band position 1526 61617; 0.5 cm ), but that for (0, 2n+1)-type CNTs are diameter dependent. The frequencies of the E . and E . modes (in the G-band region) are not only strongly diameter dependent, but also expected to converge towards one another with increasing tube diameter. This latter type of behavior can lead to erroneous classification of nanotubes as metallic or semiconducting, since partially overlapping bands in the G-band region might result in bands with diffuse shoulder, a characteristic of metallic SWCNTs. The RBMs for DWCNTs are also strongly diameter dependent and are blue shifted reference to their corresponding RBMs in the spectra of SWCNTs. The relative distance between RBMs vibrational modes in the spectrum of a desired DWCNT is larger than that for the corresponding SWCNTs. The electron density for the small sized DWCNT, (6,0)&(12,0), indicated an intertube CC chemical bonding in the excite state. 283 FB11 Post-deadline Abstract 15 min MOLECULAR MECHANISMS IN THE REPAIR OF THE CYCLOBUTANE PYRIMIDINE DIMER 11:37 ALI A. HASSANALI, DONGPING ZHONG, SHERWIN J. SINGER, Biophysics Program, Department of Physics and Department of Chemistry, The Ohio State University, Columbus, OH 43210. Exposure to far UV radiation induces DNA damage in the form of cyclobutane pyrimidine dimers (CPDs). Cyclobutane dimer lesions can be repaired by the enzyme photolyase, in which the absorption of a blue light photon initiates a sequence of photochemical events leading to the injection of an electron at the site of the CPD lesion in DNA. The electron catalyzes the repair of the cyclobutane dimer, splitting the CPD to is original pyrimidine units, and is subsequently recaptured by the photolyase protein. In this work we investigate the molecular mechanism of the repair of the cyclobutane dimer radical anion in aqueous solution using ab initio MD simulations. Umbrella sampling is used to determine a two-dimensional free energy surface as a function of the C5-C5 and C6-C6 distances. The neutral dimer is unable to surmount a large free energy barrier for repair. Upon addition of an electron, the splitting of the C5-C5 coordinate is virtually barrier less. Transition state theory predicts that the splitting of the C6-C6 bond is complete on a picosecond timescale. The free energy surface suggests that the splitting of the two bonds is asynchronously concerted. Our work is the first to explicitly include the electronic degrees of freedom for both the cyclobutane dimer and the surrounding water pocket. The ab initio simulations show that at least 30% of the electron density is delocalized onto the surrounding solvent during the splitting process. Simulations on the neutral surface show that back electron transfer from the dimer is critical for the completion of splitting: splitting of the C5-C5’ and C6-C6’ bonds can be reversed or enhanced depending on when electron return occurs. To maximize splitting yield, the back electron transfer should occur beyond the transition state along the splitting coordinate. Non-equilibrium trajectories are also conducted that begin with the electron added to a neutral unrepaired solvated CPD. Our results indicate that there are two sup-populations: the first population with the C5-C5’ bond splitting spontaneously, as indicated by our two-dimensional free energy surface, and a second population where the C5-C5’ bond remains intact over the first half of a picosecond. 284 FC. MICROWAVE FRIDAY, JUNE 26, 2009 – 8:30 AM Room: 1000 McPHERSON LAB Chair: STEPHEN COOKE, University of North Texas, Denton, Texas FC01 15 min 8:30 THE PURE ROTATIONAL SPECTRA OF ZnO IN THE EXCITED a STATE L. N. ZACK, R. L. PULLIAM and L. M. ZIURYS, Department of Chemistry, Department of Astronomy, Steward Observatory, University of Arizona, Tucson, AZ 85721. The pure rotational spectra of ZnO in the excited a electronic state have been measured using direct absorption submillimeter techniques. This molecule was synthesized by reacting zinc vapor with N O in the presence of a DC discharge. Nine rotational transitions were recorded for the ZnO, ZnO, and ZnO isotopomers in the v=0 state and data for the main isotopomer was measured in the v=1 state. All three spin components were observed for this state, each exhibiting lambda-doubling. The data were fit with a Hund case(a) Hamiltonian and rotational, spin-orbit, spin-spin, and lambdadoubling constants established. A bond length of 1.8436 Å was determined for this excited state, which is about 0.14 Å larger than that of the ground state. FC02 15 min 8:47 THE PURE ROTATIONAL SPECTRUM OF ZnS (X L. N. ZACK and L. M. ZIURYS, Department of Chemistry, Department of Astronomy, and Steward Observatory, University of Arizona, Tucson, AZ, 85721. Millimeter-wave direct-absorption techniques have been used to measure the pure rotational spectrum of ZnS (X . This work is the first spectroscopic study of ZnS in the gas phase. This molecule was produced by the reaction of zinc vapor and H S under DC discharge conditions. Eight rotational transitions were recorded for four stable zinc isotopologues of ZnS in the v = 0 state, and data were also obtained for ZnS and ZnS in the v = 1 state. The data have been analyzed and spectroscopic constants and equilibrium parameters have been determined. The equilibrium bond length of ZnS was established to be 2.0464 Å, as compared to 1.7047 Å for ZnO. FC03 15 min 9:04 MICROWAVE-MICROWAVE DOUBLE RESONANCE INVESTIGATION OF THE H -N O VAN DER WAALS COMPLEX JEN NICOLE LANDRY, WOLFGANG JÄGER, Department of Chemistry, University of Alberta, Edmonton, AB, T6G 2G2, Canada ; YOSHIHIRO SUMIYOSHI AND YASUKI ENDO, Department of Basic Science, Graduate School of Arts and Sciences, The University of Tokyo, Komaba, Meguro-ku, Tokyo 153-8902, Japan. The & =2-1 rotational transitions of #D - N O and D - N O were measured using a microwave-microwave double resonance technique. The experimental setup included a pulsed molecular beam Fourier Transform microwave spectrometer for signal detection and a microwave synthesizer with a K band standard gain horn (frequency range 18 26.5 GHz) to generate and transmit the pump radiation. The experimental arrangement was such that the pump radiation propagation was perpendicular to the supersonic molecular expansion. In these experiments, the pump radiation was tuned into resonance with the & '' =1 -0 or 1 -0 transition. The resulting population transfer from the rotational ground state facilitated the observation of the & =2-1 transition by significantly enhancing the signal intensity. In addition, a brief update on the solvation studies of nitrous oxide with H molecules will be given. 285 FC04 15 min 9:21 RECOVERY OF LEGACY PAPER SPECTRA AND NEW RESULTS ON THE ROTATIONAL SPECTRUM OF H O HF ZBIGNIEW KISIEL, Institute of Physics, Polish Academy of Sciences, Al. Lotnik ów 32/46, 02-668 Warszawa, Poland; MIKHAIL YU. TRETYAKOV, OLEG L. POLYANSKY, Institute of Applied Physics of RAS, 46 Uljanova Str., 603950 Nizhny Novgorod, Russia. The situation when a spectrum exists only in the form of a paper record and contains valuable unprocessed information is not that rare. In the case of broadband spectra with a rich information content it is very desirable to convert such spectra into a digital form that will be amenable for use with contemporary packages for graphical assignment. a The RAD spectrum of the H O HF hydrogen bonded dimer recorded in the 1980’s at Nizhny Novgorod is an example of such a valuable legacy spectrum. Only a small proportion of the lines in this spectrum have been assigned and measured. b A special software package has been written to convert the original spectrum from many strip chart records into a unified, calibrated digital spectrum, which covers the frequency region 182-352 GHz and 11 succesive & & transitions. The package is described in detail, is expected to be of universal applicability, and has been made available on the PROSPE website.c Initial results concerning the analysis of this spectrum are reported, and it is aimed to considerably improve the understanding of the internal dynamics in H O HF over that reached earlier on the basis of the cm-wave rotational spectrum.d a Z.Kisiel et al., J. Mol. Spectrosc., 233, 231-243 (2005). et al., J. Mol. Spectrosc., 241, 124-135 (2007). c Z.Kisiel, Programs for ROtational SPEctroscopy, available at http://info.ifpan.edu.pl/˜kisiel/prospe.htm. d Z.Kisiel, A.C.Legon, D.J.Millen, Proc. Roy. Soc. Lond. A, 381, 419-442 (1982). b S.P.Belov FC05 THE PURE ROTATIONAL SPECTRUM OF HPS (X̃ A ): 15 min 9:38 THE THIRD ROW ANALOG OF HNO D. T. HALFEN, Department of Chemistry, Department of Astronomy, and Steward Observatory, University of Arizona, Tucson, AZ 85721; D. J. CLOUTHIER, Department of Chemistry, University of Kentucky, Lexington, KY 40506; and L. M. ZIURYS, Department of Chemistry, Department of Astronomy, and Steward Observatory, University of Arizona, Tucson, AZ 85721. The pure rotational spectrum of HPS ( X̃ A ) has been measured using millimeter-wave direct absorption techniques in the range 229-415 GHz. This work is the first laboratory detection of this species in the gas phase. This molecule was created by the reaction of gas-phase phosphorus and H S in the presence of argon carrier gas and an AC glow discharge. The pattern of the rotational spectrum clearly indicated the presence of an asymmetric top. HPS, like HNO, has a bent structure. Data have been recorded for multiple K components from K = 0 to 6. The data have been fit with an asymmetric top Hamiltonian, and the spectroscopic parameters have been determined. The structure established from the rotational constants is in excellent agreement with ab initio calculations. Comparison with HNO suggests similar bonding in HPS despite the third row elemental substitutions. Intermission 286 FC06 PECULIAR TRAITS OF HSOH IN ITS ROTATIONAL-TORSIONAL SPECTRUM ABOVE 1 THz 15 min 10:15 O. BAUM, M. KOERBER, S. SCHLEMMER, T. F. GIESEN, I. Physikalisches Institut, Universit ät zu Köln, 50937 Köln, Germany; S. N. YURCHENKO, TU Dresden, Institut f ür Physikalische Chemie und Elektrochemie, 01062 Dresden, Germany; W. THIEL, MPI f ür Kohlenforschung, 45470 M ülheim an der Ruhr, Germany; P. JENSEN, FB C – Theoretische Chemie, Bergische Universit ät, 42097 Wuppertal, Germany; K. M. T. YAMADA, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba-West, 305-8569, Japan. In this paper we present highly accurate spectral data of oxadisulfane, HSOH, in the region of 1.1–1.3 THz. The simple skew chain molecule HSOH is an asymmetric rotor close to the limiting case of a symmetric prolate top molecule. Therefore the pure rotational spectra of this molecule appear very simple at first glance. However, if the spectra are inspected in detail, the molecule manifests its peculiarities. HSOH can be considered as a link between the well-known molecules HSSH and HOOH. For these two species a simple model to explain the alternation of the torsional splittings with the rotational quantum number ' has been proposed by Hougena. HSOH obviously has lower symmetry than HSSH and HOOH and therefore the observed variation of the torsional splittings with the rotational quantum number ' cannot be explained by the Hougen model. The new data allow to calculate the experimental tunneling splitting of energy levels up to ' =7 for the first time. The obtained results are essential to test novel models b c d on torsional tunneling splitting in HSOH. In case of ' 5 the HSOH molecule displays a dominating perpendicular-type spectrum in the vibrational ground state with strong - and somewhat weaker accompanying *-type transitions, as can be understood from theoretical values of the dipole-moment components. In contrary, transitions with ' display only - but no *-type transitions. The absence of *-type transitions is completely unexpected and yet not well understood. a J.T. Hougen and B. DeKoven, J. Mol. Spectrosc. 98 (1983) 375; J.T. Hougen, Can. J. Phys. 62 (1984) 1392 Ovsyannikov, V.V. Melnikov, W. Thiel, P. Jensen, O. Baum, T.F. Giesen, S.N. Yurchenko, J.Chem.Phys. 129 (2008) 154314 c K.M.T. Yamada, G. Winnewisser, P. Jensen, J. Mol. Struct. 695–696, (2004) 323 d K.M.T. Yamada, P. Jensen, S. Ross, O. Baum, T.F. Giesen, S. Schlemmer, J. Mol. Struct. (2009) accepted b R.I. FC07 15 min MICROWAVE SPECTRUM AND STRUCTURE DETERMINATION OF THE CCAs RADICAL 10:32 (X ) M.SUN, D. T. HALFEN, Department of Chemistry, Department of Astronomy, and Steward Observatory, University of Arizona, Tucson, AZ 85721; D. J. CLOUTHIER, Department of Chemistry, University of Kentucky, Lexington, KY 40506; and L. M. ZIURYS, Department of Chemistry, Department of Astronomy, and Steward Observatory, University of Arizona, Tucson, AZ 85721. The microwave spectrum of the CCAs radical (X ) has been measured using Fourier transform (FTMW) techniques. This species were created in a supersonic expansion by the reaction of arsenic trichloride, AsCl , and acetylene, C H , diluted in argon carrier gas, using a pulsed nozzle coupled with a DC discharge. Three rotational transitions of CCAs were measured in the frequency range of 12 to 32 GHz, in which both lambda-doubling and hyperfine interactions were observed, the latter due to the arsenic spin of I = 3/2. In addition, four rotational transitions for C CAs were measured in the frequency range of 11 to 38 GHz, as well as several transitions arising from C CAs and C CAs. In these three species, hyperfine splittings were also observed due to the C nuclei, creating complex patterns for these isotopologues. These data were analyzed with a Hamiltonian incorporating the appropriate number of nuclear spins, and effective rotational, lambda-doubling, and arsenic and carbon-13 hyperfine constants were determined. From the effective rotational constants, bond lengths for this linear species have been established. The distribution of electrons in this radical has also been inferred from the hyperfine constants. 287 FC08 15 min THE PURE ROTATIONAL SPECTRUM OF SiCl (X ) AND SiCl 10:49 (X ) D. T. HALFEN, M. SUN, and L. M. ZIURYS, Department of Chemistry, Department of Astronomy, and Steward Observatory, University of Arizona, Tucson, AZ 85721. The pure rotational spectrum of SiCl (X ) has been recorded using millimeter/submillimeter direct absorption methods. This work is the first measurement of the rotational spectrum for this species. The ion was created from SiCl in the presence of argon carrier gas and an AC discharge. Data have been recorded from 103 to 463 GHz for the main isotopologue in its ground vibrational state. Additional transitions have been measured for the Si Cl , Si Cl , and Si Cl isotopologues, and for Si Cl in the v = 1, 2, and 3 states. The rotational spectrum of Si Cl and Si Cl in their X state has also been measured using Fourier transform microwave (FTMW) techniques. The J = 2 1 and 3 2 transitions were recorded for both isotopologues in the range 22-38 GHz. The spectroscopic constants have been determined for both species using the appropriate Hamiltonian, including chlorine hyperfine parameters for SiCl. The bond length for the ion has been found to 0.115 Å shorter that for the neutral, indicating that the electron lost from SiCl to produce SiCl comes from an anti-bonding orbital. FC09 Post-deadline Abstract 15 min 11:06 OPTICAL EMISSION STUDIES OF NEW BAND SYSTEM OF SILICON DIMER RAM GOPAL, K.S.OJHA and S.C.SINGH, Laboratory of Laser Spectroscopy and Nanomaterials, Department of Physics, University of Allahabad, ALLAHABAD - 211002, INDIA. Silicon containing molecules such as SiC, SiN and 9 are of astrophysical interest and their studies provide information about the construction and evolution of different interstellar bodies. The emission spectrum of silicon dimer is recorded in the region of 360-540 nm using laser ablation technique. A rotating silicon rod of high purity, placed in the ablation chamber under argon atmosphere of 0.1 torr pressure, is irradiated with focused output of 355 nm from pulsed Nd:YAG laser. The plasma thus produced by laser ablation is allowed to cool for 300 ns and emission from the cooled plasma is collected on the entrance slit of Spex TRIAX 320M monochomator with ICCD detector system. About 96 bands including 22 bands reported by previous workers are observed. All these bands are assigned into two new band systems H’- , I- , and three already reported - , ' and I - band systems of silicon dimer. Out of these 96 bands, 43 bands are assigned to two new band system H’-D and I-X while 33 bands including 17 bands reported by earlier workers in this region are assigned to H-X system of 9 molecule. In addition to these bands, two bands are assigned to K-X system while the three bands reported by /.= and /*9/ and Leclercq are marked to L-D system. The detailed analyses of these systems are investigated in present work. The (0,0) band of H-X system is observed for the first time during this investigation. The molecular constants along with dissociation energies and internuclear distances are calculated from the observed spectra. %%/.= %&%" #2% %/*9 %I0=0A %&%" #2 FC10 Post-deadline Abstract 15 min 11:23 STRUCTURAL STUDY OF POLAR LIQUIDS THROUGH DIELECTRIC STUDY USING TIME DOMAIN REFLECTOMETERY SURESH C.MEHROTRA, Department of Computer Science & Information Technology, Dr. Babasaheb Ambedkar Marathwada University, Aurangabad 431 004.India. The microwave group at Dr. Babasaheb Ambedkar Marathwada University has reported dielectric relaxation studies on many binary polar liquids The results have been explained qualitatively by assuming formation of multimers in the binary polar liquid. However, no attempt has been yet made to explain the result quantitatively by any group. There is usual practice in the field to explain the experimental dielectric results by assuming their breaking of multimers or formation of multimers. The objective of the present talk is to provide information about experimental aspects of Time Domain Methods along with theoretical models to extract information regarding liquid structure. 288 FC11 Post-deadline Abstract 15 min 11:40 THE PURE ROTATIONAL SPECTRUM OF TIS (X ) IN ALL THREE SPIN COMPONENTS R. L. PULLIAM, and L. M. ZIURYS, Department of Chemistry, Department of Astronomy, Steward Observatory, University of Arizona, Tucson, AZ 85721. The pure rotational spectrum of TiS in the X ground state has been measured using millimeter-wave direct absorption techniques. This species was created by the reaction of hydrogen sulfide gas with titanium vapor produced in a Broida oven which was modified to withstand the extreme temperatures required to melt this metal. Eight transitions have been recorded, each consisting of three spin components. No lambda-doubling was observed, as expected for a state. The data were fit with a Hund’s case(a) Hamiltonian and spectroscopic constants have been determined. The results from this study, as well as a comparison to past optical data will be presented. FC12 Post-deadline Abstract ABSOLUTE O 15 min 11:57 NMR SCALE: A JOINT ROTATIONAL-SPECTROSCOPY AND QUANTUM-CHEMISTRY STUDY CRISTINA PUZZARINI, GABRIELE CAZZOLI, Dipartimento di Chimica ”G. Ciamician”, Universit à di Bologna, I-40126 Bologna, Italy; MICHAEL E. HARDING, J ÜRGEN GAUSS, Institut für Physikalische Chemie, Universität Mainz, D-55099 Mainz, Germany. The Lamb-dip technique has been employed for resolving the hyperfine structure (hfs) of rotational lines of H O. Hfs is due to O for para-H O lines and to the O and H nuclei for ortho-H O lines. The high resolution of such a technique allowed us to obtain the hyperfine parameters to a very good accuracy. The experimental determination has been strongly supported by highly accurate quantum-chemical calculations of the hyperfine parameters involved (spin-rotation constants of O as well as H, and O-H and H-H direct spin-spin interaction constants). Then, the experimental spinrotation constants of O have been used for evaluating the paramagnetic contributions to the magnetic shielding constants, whereas the diamagnetic ones have been accurately computed by means of CCSD(T) calculations. These steps are part of a well-tested procedure, which also involves the determination of vibrational and temperature corrections. The overall result is an alternative experimental absolute NMR scale for oxygen. 289 FD. MINI-SYMPOSIUM: CAVITY ENHANCED SPECTROSCOPY FRIDAY, JUNE 26, 2009 – 8:30 AM Room: 1015 McPHERSON LAB Chair: ANDREW ORR-EWING, University of Bristol, Bristol, United Kingdom FD01 INVITED TALK CAVITY-ENHANCED OPTICAL FREQUENCY COMB SPECTROSCOPY 30 min 8:30 JUN YE, MICHAEL J. THORPE, FLORIAN ADLER, and KEVIN C. COSSEL, JILA, NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY AND UNIVERSITY OF COLORADO, BOULDER, CO 803090440. Cavity-enhanced optical frequency comb spectroscopy is a new technique that realizes simultaneously broad spectral coverage and high spectral resolution provided by an optical frequency comb as well as ultrahigh detection sensitivities enabled with a high-finesse optical cavity [1]. These powerful capabilities have been demonstrated in a series of experiments where real-time detection and identification of many different molecular states or species are achieved in a massively parallel fashion [2,3]. We will discuss the principle, technical requirements, and various implementations for this spectroscopic approach, as well as applications that include trace gas detections, human breath analysis, and characterization of cold and ultracold molecules [4,5,6]. References: [1] M. J. Thorpe, K. D. Moll, B. Safdi, and J. Ye, Science 311, 1595 (2006). [2] M. J. Thorpe, D. D. Hudson, K. D. Moll, J. Lasri, and J. Ye, Opt. Lett. 32, 307 (2007). [3] C. Gohle, B. Stein, A. Schliesser, T. Udem, and T. W. Hänsch, Phys. Rev. Lett. 99, 263902 (2007). [4] M. J. Thorpe, D. Balslev-Clausen, M. Kirchner, and J. Ye, Opt. Express. 16, 2387 (2008). [5] M. J. Thorpe and J. Ye, Appl. Phys. B 91, 397 (2008). [6] M. J. Thorpe, F. Adler, K. C. Cossel, M. H. G. de Miranda, and J. Ye, Chem. Phys. Lett. 468, 1 (2009). FD02 10 min 9:05 PSEUDO-RANDOM AMPLITUDE OR TONE BURST MODULATION COMBINED WITH CAVITY-ENHANCED DETECTION CHRIS HOVDE, Southwest Sciences Ohio Operations, Cincinnati OH 45244 ; STEVE M. MASSICK and DAVID S. BOMSE, Southwest Sciences, Santa Fe NM 87505. Combining pseudo random-modulation techniques with cavity enhanced spectroscopy allows the estimation of both optical path length and absorption while using a cw diode laser as the light source. Two pseudo-random modulation approaches are described, in each case combined with an off-axis cavity consisting of two cylindrical mirrors oriented to produce a dense pattern of cavity modes. In one approach, the amplitude of the laser is modulated; deconvolution results in an exponential ring-down decay curve. In the second approach, tone bursts that modulate the laser frequency are switched on and off with a pseudo-random code. Deconvolution yields the first derivative of an exponential whose amplitude is proportional to absorbance. With either approach the dynamic range of the transmitted intensity is much smaller than for a ring-down experiment, allowing high gain before the signal is digitized. Initial experimental results measuring carbon monoxide are presented, and the dependence of detection sensitivity on experimental parameters such as pseudo-random clock rate is discussed. 290 FD03 15 min 9:17 THE APPLICATION OF HIGH-REPETITION-RATE CAVITY RINGDOWN TECHNIQUES TO INFRARED SPECTROSCOPY BRIAN M. SILLER, and BENJAMIN J. McCALL, Department of Chemistry, University of Illinois, Urbana, IL 61801. Our group has been applying continuous-wave cavity ringdown spectroscopy to systems of supersonic jets, plasmas, and ion beams using diode, difference frequency, and quantum cascade lasers. We use these techniques to take spectra of molecular ions and large neutral molecules, such as C , at wavelengths in the near- and mid-IR. Our traditional method of collecting ringdowns, which involves sweeping the cavity length over several free spectral ranges and diverting the laser when buildup events are observed, has allowed us to achieve a repetition rate of tens of ringdowns per second with a minimum detectable absorbance of cm .a In an effort to increase our sensitivity, we have embarked on a program to implement high-repetition-rate ringdown, in a setup similar to that of the Halonen Group. b This change requires locking the laser frequency to the cavity length using the Pound-Drever-Hall method. Since the laser and the cavity are always in resonance, the ringdown collection rate can be improved to thousands per second. We will present our progress, including the generation of error signals, the construction of the locking electronics, the data acquisition process, and our experimental results. a S. b R. L. Widicus Weaver, M. B. Wiczer, B. Negru, J. P. DiGangi, B. A. Tom and B. J. McCall, J. Mol. Spec., 249, 14-22 (2008). Z. Martı́nez, M. Metsälä, O. Vaittinen, T. Lantta, and L. Halonen, J. Opt. Soc. Am. B., 23, 727-740 (2006). FD04 15 min 9:34 AN OFF AXIS CAVITY ENHANCED ABSORPTION SPECTROMETER AND A RAPID SCAN SPECTROMETER WITH A ROOM-TEMPERATURE EXTERNAL CAVITY QUANTUM CASCADE LASER XUNCHEN LIU, CHEOLHWA KANG, and YUNJIE XU , Department of Chemistry, University of Alberta, Edmonton, Canada. Quantum cascade laser (QCL) is a new type of mid-infrared tunable diode lasers with superior output power and mode quality.a Recent developments, such as room temperature operation, wide frequency tunability, and narrow line width, make QCLs an ideal light source for high resolution spectroscopy. Two slit jet infrared spectrometers, namely an off-axis cavity enhanced absorption (CEA) spectrometer and a rapid scan spectrometer with an astigmatic multi-pass cell assembly, have been coupled with a newly purchased room temperature tunable mod-hop-free QCL with a frequency coverage from 1592 cm to 1698 cm and a scan rate of 0.1 cm /ms.b Our aim is to utilize these two sensitive spectrometers, that are equipped with a molecular jet expansion, to investigate the chiral molecules-(water) clusters. To demonstrate the resolution and sensitivity achieved, the rovibrational transitions of the static N O gas and the bending rovibrational transitions of the Ar-water complex, c a test system, at 1634 cm have been measured. a D. Hofstetter and J. Faist in High performance quantum cascade lasers and their applications, Vol.89 Springer-Verlag Berlin & Heidelberg, 2003, pp. 61-98. b Y. Xu, X. Liu, Z. Su, R. M. Kulkarni, W. S. Tam, C. Kang, I. Leonov and L. D’Agostino, Proc. Spie, 2009, 722208 (1-11). c M. J. Weida and D. J. Nesbitt, J. Chem. Phys. 1997, 106, 3078-3089. FD05 LONG TERM STABILITY IN CW-CRDS EXPERIMENTS 15 min 9:51 HAIFENG HUANG, Department of Chemistry, University of Virginia, Charlottesville VA, 22904-4319; KEVIN K. LEHMANN,. Allan variance can be used to characterize the slow drift of CW cavity ring-down spectroscopy (CW-CRDS) system, caused by the instability of experimental environments. By including the differential measurement of on- and off-peak decay rates in the system, the drifting of both decay rates can cancel out greatly. A sensitivity of % cm during an optimum integration time of 15.4 minutes has been obtained with our CW-CRDS system. This sensitivity corresponds a 3! methane detection limit of 0.3 parts per billion by volume (ppbv) in N at 20 torr or 37 parts per trillion by volume (pptv) in N at 760 torr measurement pressure, near 1.65 m laser wavelength. 291 Intermission FD06 15 min 10:20 THE INFLUENCE OF FREE-RUNNING FP-QCL FREQUENCY JITTER ON CAVITY RINGDOWN SPECTROSCOPY OF C BRIAN E. BRUMFIELD, JACOB T. STEWART, Department of Chemistry, University of Illinois at UrbanaChampaign, Urbana, IL 61801; MATTHEW D. ESCARRA, CLAIRE F. GMACHL, Department of Electrical Engineering, Princeton University, Princeton Institute for the Science and Technology of Materials, Princeton, NJ 08544; BENJAMIN J. McCALL, Departments of Chemistry and Astronomy, University of Illinois at Urbana-Champaign, Urbana, IL 61801. Our group is engaged in an effort to acquire a high-resolution gas phase spectrum of buckminsterfullerene in the mid-IR. To achieve this goal, we have constructed a continuous-wave cavity ringdown spectrometer (cw-CRDS) using a FabryPerot quantum cascade laser (FP-QCL) as the principal light source. The cw-CRDS technique has the beneficial aspects of both high sensitivity and high resolution. When aligning the high finesse cavity of the spectrometer a light source with a stable narrow linewidth is preferable as this leads to a regular occurrence of build-up events correlated to the sweep of the piezoelectric transducer. The regular interval during the sweep of the cavity resonances over the frequency of the laser source can be a useful aid by providing insight into the quality of the mode-matching. The instantaneous linewidth of a free-running quantum cascade laser operating in cw mode is sub-MHz, but frequency jitter from mechanical, optical, and/or electrical perturbations evidently yields a time averaged effective linewidth that is substantially broader. This frequency jitter, and the resulting time averaged linewidth, will therefore have an impact on the cw-CRDS system we are using for C spectroscopy. To characterize the effective linewidth, we have conducted self-pressure broadening studies of select SO rovibrational lines in the vibrational band via direct absorption spectroscopy using FP-QCLs intended for C spectroscopy, and have measured a time-averaged effective linewidth of 120 MHz. We will discuss the self-pressure broadening coefficients measured for select rovibrational lines of SO between 1194-1198 cm , the implications of the measured frequency jitter of our laser source on cw-CRDS data collection, and a progress report on our C spectroscopy project. FD07 ANYTHING BUT TWO MIRRORS: CRD IN WAVEGUIDE CAVITIES. 15 min 10:37 JACK BARNES, KLAUS BESCHERER, STEPHEN BROWN, CATHLEEN M. CRUDDEN, JESSICA LITMAN, HANS-PETER LOOCK, RICHARD D. OLESCHUK, and HELEN WAECHTER, Queen‘s University, Dept. of Chemistry, Kingston, ON, K7L 3N6, Canada. Phase-shift CRD measurements were used to determine the optical loss in a variety of unusual optical cavities. Cavities were made of – loops of optical fibers, – circular channels containing a high refractive index liquid, – strands of single-mode fiber using Bragg gratings as mirrors, – microresonator spheres made from silica and polydimethyl siloxane and, – silicon-on-insulator “race track“ microresonators. These cavities were interfaced to (micro-)analytical separation systems such as microfluidic labs-on-a-chip, capillary electrophoresis and high-performance liquid chromatography (HPLC). As the sample interacts with the cavity, the ring-down time is decreased and absorption detection of small liquid samples is possible. CRD measurements in waveguide cavities may also be extended to very sensitive refractive index measurements. By exploiting the response of long-period gratings and microresonators to refractive index changes, ppb-level chemical detection was carried out in water and air. 292 FD08 15 min 10:54 RAYLEIGH SCATTERING CROSS SECTION MEASUREMENTS WITH A THREE MIRROR RING CAVITY DOUGLAS S. KURAMOTO, and RICHARD N. ZARE, Department of Chemistry, Stanford University, Stanford, CA 94305; ALEXANDER A. KACHANOV, Skymoon Ventures, Santa Clara, CA 95054. Most optical cavities in cavity ring-down spectroscopy consist of two mirrors. Using a more complicated cavity design, such as one with three mirrors, can lead to advantages such as reducing the effect of baseline variations due to reflections between the cavity mirror and the laser. A three mirror cavity in the ring configuration has been developed which uses the backward traveling wave to provide feedback to an external cavity diode laser. Measurements of Rayleigh scattering cross sections using this setup will be discussed. FD09 15 min 11:11 CAVITY ENHANCED ABSORPTION SPECTROSCOPY USING A BROADBAND PRISM CAVITY AND A SUPERCONTINUUM SOURCE PAUL S. JOHNSTON, Department of Chemistry, University of Virginia, Charlottesville VA, 22904-4319; KEVIN K. LEHMANN,. The multiplex advantage of current cavity enhanced spectrometers is limited by the high reflectivity bandwidth of the mirrors used to construct the high finesse cavity. Previously, we reported the design and construction of a new spectrometer that circumvents this limitation by utilizing Brewster s angle prism retroreflectors. The prisms, made from fused silica and combined with a supercontinuum source generated by pumping a highly nonlinear photonic crystal fiber, yields a spectral window ranging from 500 nm to 1750 nm. Recent progress in the instruments development will be discussed, including work on modeling the prism cavity losses, alternative prism material for use in the UV and mid-IR spectral regions, and a new high power supercontinuum source based on mode-locked picosecond laser. FD10 AMPLIFIED FIBER-LOOP RINGDOWN SPECTROSCOPY 10 min 11:28 JESSICA LITMAN, JACK BARNES and HANS-PETER LOOCK, Department of Chemistry, Queen‘s University, Kingston, Ontario, Canada. Many commercial liquid chemical analysis systems, such as high-performance liquid chromatography (HPLC) or capillary electrophoresis consist of a separation followed by optical detection. Besides small volumes and low detection limits, the system should also allow the detection of a large variety of analytes. Existing absorption and fluorescence detectors are often not very sensitive or require labelling. Here, an absorption detector is presented based on cavity ring-down spectroscopy (CRDS) where the optical cavity is made from fibre optic waveguides and the light source is a continuous wave (cw) diode laser. The purpose of this project is to increase the detection of analytes through their overtone absorption in the telecom region at 1300 to 1500 nm. This is done by increasing the ratio of desired loss (extinction caused by the sample), to undesirable loss (due to the waveguides or solvents) through amplification of the ringdown signal using a gain-clamped erbium doped fibre amplifier (EDFA). The amplified cavity has a round-trip time of 750 ns and we achieved a detection limit of at most 250 ppm when measuring acetylene at 1532.83 nm. The application of our method to detection of dissolved analytes or particles in liquids will be discussed. 293 AUTHOR INDEX A ABAD, G. G. – TI08 ABRAMENKOV, A. V. – MG12, WG08 ADAM, A. G. – RF03, RF11 ADAMS, C. L. – TF01 ADLER, F. – FD01 AFSHARI, M. – MG11, RA01, RA02, RA03, RA04, RA05 AHMED, M. – WI15 AKINS, D. L. – FB10 AL-BASHEER, W. – MI06, RB01 ALBERDING, B. G. – MF08 ALBERT, K. K. – MG07 ALBERT, S. – MG07, WG04 ALEKSEEV, E. A. – MH14 ALEKSEEV, V. A. – MI15, MJ08 ALLAMANDOLA, L. J. – RG10 ALLARD, O. – MI04 ALLEN, N. – TI08 ALONSO, J. L. – MH12, TA01, TA02, TA03, RC08 ALQARADAWI, S. Y. – FB08 ALVAREZ-VALTIERRA, L. – TB06, FA11 AMANO, T. – TC04, WF12, RG12 AMBERGER, B. K. – RC03 AMICANGELO, J. C. – MJ09 AMYAY, B. – WG01 AN, D. – WI02 ANCILOTTO, F. – MI04 ANDERSON, D. T. – MJ04, MJ05, WF09 ANNEN, K. – TG14 ANNESLEY, C. J. – WF08 ANTONOV, I. O. – TI07 ARENDT, R. – WI02 ARUNAN, E. – RC06, RC07, FB09 AUBÖCK, G. – MI04, WJ08 AUWERA, J. V. – TC02 AXNER, O. – TD08 AYDIN, M. – FA08, FB10 B BABA, M. – TJ07, WA02 BAIDAR, S. – RF14 BALABIN, R. M. – RA09 BALCO, D. – TG04, TG05 BANDYOPADHYAY, B. – MG06, TE12, RB02, RB03 BAO, J. – MF02 BAR, I. – WG12 BARANOV, Y. I. – TI12, RI02 BARBE, A. – TG12 BARDAKCI, T. – WG09 BAREFOOT, N. Z. – MH15 BARKER, B. J. – RF14 BARKER, J. R. – RE08 BARNES, J. – FD07, FD10 BAUERECKER, S. – MG07 BAUM, O. – FC06 BAUMANN, C. A. – MJ11 BEAMES, J. M. – RD07 BECK, J. P. – MG08 BECKERS, H. – TI04, RI06 BECKLIN, E. E. – TH04, TH05 BEGUE, N. J. – FB06 BELLERT, D. J. – RB06, FB05 BELLOCHE, A. – TC08, WI06 BENDERSKII, A. V. – MF07 BENETIS, N. – MJ07 BENNER, D. C. – RI12, RI13, RI14 BERG, M. – TE03 BERGIN, E. A. – RG13 BERKE, A. E. – WF08 BERMEJO, D. – WG11 BERNATH, P. F. – TI08, TI09, RF12 BERNHARDT, B. – TG01, TG02 BESCHERER, K. – FD07 BHATTA, R. S. – FB04 BIENNIER, L. – FB09 BILLINGHURST, B. – TG06 BILLINGHURST, B. E. – TG07 BING, D. – TE03 BIRD, R. G. – TA04, RC11 BIRK, M. – TG09 BLAKE, G. A. – RG01 BLAKE, T. A. – RI13, RI14 BLANCO, E. A. – WG06 BLANCO, S. – TA01, TA03 BOCK, C. W. – MG12 BOHN, R. K. – TA08 BOMSE, D. S. – FD02 BONDYBEY, V. E. – MI09, MI10, TJ12 BOOGERT, A. – WI02 BOONE, C. – TI08, TI09 BOOPALACHANDRAN, P. – WG07 BORVAYEH, L. – RG16 BOUCHER, D. S. – MF01 BOUDON, V. – TC02, RH03, RI09, RJ06 BOUWMAN, J. – RG10 BOYÉ-PERONNE, S. – RG11 BRAND, C. – WJ02, WJ03 BRAUER, C. S. – TC06, TC07, TH13, WH10, WH13 BREEN, K. J. – WG02, WG03 BRINEY, K. A. – MF01 BRINKMANN, N. R. – RB07 BROCKHINKE, A. – TD01 BROWN, L. R. – RI11, RI12 BROWN, S. – FD07 BROWN, S. S. – RD01 BRUBACH, J. – TG04, TG05 BRUMFIELD, B. E. – FD06 BRÜNKEN, S. – WI06, RG08 BRÉCHIGNAC, P. – RG09 BUCHANAN, E. G. – TB02, TB09, WG13 BURROWS, J. P. – RI08 BURSTEN, B. E. – RJ12 C CABEZAS, C. – TA01 CALLEGARI, C. – MI04, MJ01, WJ08 CAMINATI, W. – MH08, TA06, RC09, RC13, RH06 CAMPARGUE, A. – TG12 CAPASSO, F. – TG03 CARPENTIER, Y. – RG09 CARRIER, S. L. – WF04 CARVAJAL, M. – TC11 CASE, A. S. – FB03 CASEY, S. M. – RF14 CASTLEBERRY, V. A. – RB06, FB05 CASTO, C. – TH08 CAZZOLI, G. – FA09, FC12 CEPONKUS, J. – TI05 CHAKRABORTY, T. – MG06, TJ14, TJ15 CHALYAVI, N. – TJ09 CHANDRASEKARAN, V. – FB09 CHANG, C. – TJ11 CHAO, J. – TJ03 CHAVEZ, M. P. – MI14 CHELIN, P. – RI02 CHEN, A. – TJ06 CHEN, H. – TG11 CHEN, K. C. – FB07 294 CHEN, K. M. – FB07 CHEN, L. – RG14, RJ08 CHEN, M. – TF13, WJ10 CHEN, Z. – MH09, TC03 CHENG, T. – TE12, RB02, RB03 CHEUNG, A. S. – RF05, RF06 CHHANTYAL-PUN, R. – TJ08 CHISHOL, M. H. – MF09 CHISHOLM, M. H. – MF08, TB07 CHU, L. – TI03 CHUNG, C. – TG11 CIAFFONI, L. – TD02 CLADY, R. G. C. R. – TJ09 CLASP, T. N. – MG04 CLEMENTS, C. L. – TB01, TB06 CLOUTHIER, D. J. – TJ04, TJ05, TJ06, RH12, FC05, FC07 COBB, R. H. – TG15 COHEN, E. A. – TA06 COHEN, K. – MJ11 COLE, R. – TD09 COLOMBO, A. P. – RH07 CONRAD, A. R. – MH15 CONTRERAS, C. S. – TC05 COOKE, S. A. – MH05, MH06, MH13, TA09, WF13 COPELAND, R. A. – TI06 CORTIJO, V. – MH12 COSSEL, K. C. – FD01 COTERA, A. – WI02 COUDERT, L. H. – MH03, TC11, RI02, FA05 COUTENS, A. – TC08 COXON, J. A. – MI01 COY, S. L. – MI07 CRABTREE, K. N. – TE04, TE05, TE06, WH02 CRAIG, N. C. – TA12, WG07 CRAWFORD, T. J. – RI11 CRESPO-HERNÁNDEZ, C. E. – MF12 CRIM, F. F. – MF01, WF04, WF08, FB03 CROWTHER, A. C. – WF04 CRUDDEN, C. M. – FD07 CURL, R. F. – TF11, WJ10 D DAILY, J. W. – MJ12 DALY, A. M. – RC10 DARR, J. P. – WF02 DATTANI, N. S. – MI02 DE BACKER-BARILLY, M.- R. – TG12 DE GHELLINCK, X. – TD06 DE LUCIA, F. C. – TC09, TH08, TI10, TI11, WF06, WF07, WH01, WH04, WH05 DE MARÉ, G. R. – WG08 DEB, S. – FB02 DEE, S. J. – RB06, FB05 DEHGHANY, M. – MG11, RA01, RA02, RA03, RA04, RA05 DEMAISON, J. – TD07, RH03 DEMPSEY, L. P. – WJ09 DEMYK, K. – TC11 DESBOIS, T. – RD03 DEVASHER, R. B. – TG15 DEVI, V. M. – RI12, RI13, RI14 DEWBERRY, C. T. – MH05, MH06, MH13, WF13 DICK, M. J. – TH09 DICKSON, N. M. – MF04 DIDRICHE, K. – TD06, TD07 DIEHL, L. – TG03 DIEZ-Y-RIEGA, M. H. – MJ10 DIJK, C. V. – MH09 DIKEN, E. G. – WG02 DIXNEUF, S. – TD04 DMITRIEV, Y. A. – MJ07 DOLGIKH, S. A. – FA03 DOMANSKAYA, A. – RI09 DOMENECH, J. L. – WG11 DONEHUE, J. E. – MF04 DONG, F. – TF06 DORAN, J. L. – RC05 DOUBERLY, G. E. – MG09, MJ02 DOUIN, S. – RG11 DOWNIE, L. E. – RF03, RF11 DRAKE, T. L. – RC02 DROUIN, B. J. – TA06, TC06, TC07, TH06, TH09, TH10, TH13, WH08, WH09, WH10, WH11, WH12, WH13 DUMESH, B. S. – MJ13 DUNBAR, R. C. – RB10 DUNCAN, B. – TI09 DUNCAN, M. A. – MG09, MG10, TE12, RA08, RB02, RB03 DUNKELBERGER, A. D. – MF01 DUNN, M. E. – WG05 DUNNING JR., T. H. – RJ07, RJ08 DURIG, J. R. – WG10 DUXBURY, G. – TG08, TG10, TG13 DYUBKO, S. F. – MH14 E EBBEN, C. – TF05 EDDINGSAAS, N. – TI01, WJ11, RD02 EGUCHI, T. – RA11 EIKEMA, K. S. E. – MI11 EL-KHOURY, P. Z. – WJ06 ELLIOTT, B. – MG01 ELLIOTT, B. M. – MG02 ELLIS, B. – TJ05, TJ06 ELLISON, G. B. – MJ12, TF14 ENDO, Y. – FC03 ENDRES, C. P. – TH11 EPIFANOVSKY, E. – FA01 ERNST, W. E. – MA01, MI04, MJ01, WJ08 ERVIN, K. M. – TF01, TF03 ESCARRA, M. D. – FD06 ETCHISON, K. C. – WF13 EVANGELISTI, L. – RH06 F FARAJI, S. – WJ04 FAVERO, L. B. – RH06 FAWZY, W. M. – TE08 FAYT, A. – WG01 FEDERMAN, S. R. – WI04 FEDOROV, I. – WJ05 FEHNEL, R. R. – MJ14 FERGUSON, E. E. – MG01 FIELD, R. W. – MI07, RH07 FIELDS, B. – WI01 FILSINGER, F. – TJ10, WF05 FLEISHER, A. J. – TB01, TB05, TB06, TJ13 FOLDES, T. – RD03 FOLTYNOWICZ, A. – TD08 FONTE, M. D. – RB08 FORAN, S. J. – RF03 FORD, K. B. – TE06, WH02 FORTHOMME, D. – RF03, RF11 FORTMAN, S. – TC09 FORTMAN, S. M. – WH04, WH05 FOURNIER, J. A. – TA08 FREEDMAN, A. – RD06 FREY, S. E. – RB06, FB05 FRIEDEL, D. N. – WI01, WI05, RG06 FUJIHARA, A. – RA06, RA11 FUJITAKE, M. – RG15 FUKE, K. – RA06, RA11 295 G GALUE, H. A. – RG11 GAMACHE, R. R. – RI03, RI04 GANGULY, A. – WG10 GAO, A. – FB04 GARCIA, G. – RG11 GARDENIER, G. H. – WG02, WG03, RA10 GAUSS, J. – TI02, RC01, FA09, FC12 GEBALLE, T. R. – WI09, RG05 GEHRZ, R. D. – TH04, TH05 GELLMAN, S. H. – WG13 GEORGES, R. – RI09, FB09 GERARDI, H. K. – WG02, WG03 GHARAIBEH, M. – TJ06 GHARAIBEH, M. A. – RH12 GIESEN, T. F. – MJ13, FC06 GIRI, R. – TB11 GIULIANO, B. M. – RC13, RH06 GMACHL, C. F. – FD06 GOLAN, A. – WG12 GOMEZ, L. – RI07 GOOTEE, M. J. – MI14 GOPAL, R. – FC09 GORDON, E. B. – TE01 GORDON, I. E. – RI01 GOSWAMI, M. – RC06 GOTTLIEB, C. A. – WI06, WI16, RG07, RG08 GOUBET, M. – MH11, MH14, TC10 GOUNEV, T. K. – WG10 GRABOW, J. – MH07 GRABOW, J.- U. – TC08 GRAFF, D. L. – TI11 GRANGER, A. D. – RF03, RF11 GRIGOROVÁ, E. – TI04 GRILJ, J. – WJ07 GRILLI, R. – TD02 GRIMMINGER, R. A. – TJ05 GRONER, P. – MH04 GRUBBS II, G. S. – MH05, MH06, MH13, TA09, WF13 GUASCO, T. L. – MG02, WG02, WG03 GUELACHVILI, G. – TG01, TG02 GUILLEMIN, J. C. – MH11 GUILLEMIN, J.- C. – TC11 GUIRGIS, G. A. – MH10, WG10, RH08 GUO, L. – MF11, WG13 GUSS, J. S. – TD05 GUSTAFSON, T. L. – MF04 H HAAS, Y. – RE03 HAASE, C. – WH06 HAJIGEORGIOU, P. G. – MI01 HALEVI, A. – RB11 HALFEN, D. T. – RC01, RG02, FC05, FC07, FC08 HALONEN, L. – TD05 HAN, F. – WH03 HAN, J. – MI03 HANSEN, J. L. – TJ10, WF05 HARADA, N. – WI13 HARDING, M. E. – TI02, FC12 HARE, P. M. – RE05 HARGROVE, J. – RD04 HARPE, K. D. L. – RE04 HARRIS, R. A. – RF01, RF02, RF08 HARRISON, J. J. – TI08 HARTER, W. – RJ05, RJ06 HASSANALI, A. A. – FB11 HASSEL, G. E. – RG13 HAUSER, A. W. – WJ08 HAVEY, D. K. – RD09, RD10 HAY, K. G. – TG08, TG10, TG13 HAYASHI, N. – RG15 HE, S. – TJ04, TJ06 HEAVEN, M. C. – MI03, MI09, MI10, TI07, TJ12, RJ11 HENDRIXSON, V. – TG16 HERBERT, J. M. – RE06, RJ10, FA02, FA04 HERBST, E. – WI07, WI13, RG13 HERMAN, L. V. – MF01 HERMAN, M. – TD06, TD07, WG01 HERNDON, S. C. – RD06 HIDALGO, D. R. – FA06 HIGGINS, A. J. – RH09 HIGGINS, R. D. – TH12 HIGUCHI, H. – RG15 HINKLE, C. E. – WF11, RJ04 HINKLE, K. H. – WI10 HIRANO, T. – WF12 HIROTA, E. – TA10, TA11, TJ07 HOBBS, L. M. – WI10 HODGES, J. T. – RD09, RD10 HOLLENSTEIN, U. – MI11 HOLLIS, J. M. – WI05, RG04 HOLMEGAARD, L. – TJ10, WF05 HOLZWARTH, R. – TG01, TG02 HON, B. J. – RC05 HOPKINS, W. S. – RF11 HORNEMAN, V.- M. – RG16 HORVATH, S. – MI13, WF03 HOUGEN, J. T. – MH02, WH08, RH05, RJ01 HOVDE, C. – FD02 HSU, Y. – TJ03 HU, W. – TJ03 HUANG, H. – FD05 HUANG, X. – TH07 HUET, T. R. – MH03, TC10, TC11 HÄNSCH, T. W. – TG01, TG02 I ILYUSHIN, V. V. – MH02, TC10 INDRIOLO, N. – WI09, WI10 IRWIN, D. G. – MJ09 ISHIKAWA, H. – RA06, RA11 ISHIWATA, T. – TJ07 J JACOBSON, L. D. – FA04 JACOX, M. E. – TE07, TF12 JACQUET, P. – TG01, TG02 JACQUEY, M. – TG01 JAMES III, W. H. – MF05, MF06, TB02, TB09, TB10, WG13 JEGOUSO, D. – MH03 JENSEN, P. – FC06 JEWELL, P. R. – RG04 JOHNSON, M. A. – MG01, MG02, WG02, WG03, RA10 JOHNSON, P. M. – TJ11 JOHNSTON, P. S. – FD09 JONAS, D. M. – WJ01 JUST, G. M. P. – TF08, TF09 JÄGER, W. – MJ03, RH01, FC03 K KABIR, M. H. – TI07 KABLE, S. H. – TJ09 KACHANOV, A. A. – FD08 KAHAN, A. – RE03 KALKMAN, I. – WJ03 KALOGERAKIS, K. S. – TI06, WI15 KAMRATH, M. – MG01 KAMRATH, M. Z. – MG02 KANG, C. – FD04 KANG, L. – RH12 KANZAWA, K. – TJ07 KAO, Y. – MF11 KASAHARA, S. – TJ07 296 KASSI, S. – TD06 KAUFFMAN, C. A. – TE04, TE05 KAWASHIMA, Y. – TA10, TA11 KEBABIAN, P. L. – RD06 KEMBALL, A. – WI01 KETTWICH, S. C. – WF09 KHISTYAEV, K. – RJ13 KIM, J. – TD03 KIM, M. H. – RE10 KISIEL, Z. – MH02, TC09, WH10, RH14, FC04 KISTLER, K. – RE07 KISTLER, K. A. – RE02 KITNEY, K. A. – WJ01 KJAERGAARD, H. G. – WG05 KLAASSEN, J. J. – WG10 KLEINER, I. – TC10, TC11, RH05 KLESHCHEVA, M. – TE02 KO, H. T. – TF05 KOBAYASHI, K. – RG15 KOCH, M. – MJ01 KOELEMEIJ, J. C. J. – MI11 KOERBER, M. – FC06 KOHLER, B. – RE04, RE05 KOHSE-HÖINGHAUS, K. – TD01 KOKKIN, D. L. – WI14, RG08 KONG, W. – WH03 KOPUT, J. – WF06, WF07 KOUBEK, J. – RI06 KOWSKI, L. P. – WH10 KOZAK, C. – RE07 KOZIOL, L. – WJ05 KRASNICKI, A. – TC09, RH14 KRASNOKUTSKI, S. – TE09 KRECKEL, H. – TE03, TE06, WH02 KRYLOV, A. I. – WJ05, RJ13, FA01, FA03 KUKOLICH, S. G. – TA07, RC10 KUMAR, T. J. D. – RE08 KUMARI, S. – RB04, RB05 KUMRU, M. – WG09 KUO, H.- L. – WI05 KURAMOTO, D. S. – FD08 KUWANO, M. – RG15 KUYANOV-PROZUMENT, K. – RH07 KWABIA-TCHANA, F. – TG04 KÖHLER, M. – TD01 KÖPPEL, H. – WJ04 KÜHNEMANN, F. – MG12 KÜPPER, J. – TJ10, WF05, WJ02, WJ03 L LAANE, J. – WG07 LAASER, J. E. – WG02, WG03 LABOREN, I. E. – RB06, FB05 LAFFERTY, W. J. – TD07, TI12 LAKSHMI P., A. – RC07 LAM, C. S. – TF14 LAMBERT, D. L. – WI04 LANDAU, A. – RJ13 LANDRY, J. N. – FC03 LANE, J. R. – WG05 LANGE, A. W. – RE06 LANGFORD, N. – TG08, TG10, TG13 LARAIA, A. L. – RI03 LARICHEVA, E. N. – WJ07 LARKIN, J. D. – MG12 LATTANZI, V. – TE10, WH12, RC01 LAU, K. C. – TF14 LAUZIN, C. – TD06, TD07 LE BRIS, K. – RI10 LE ROY, R. J. – MI02, MI08, WA01, WF12, FB01 LE, A. – RF10 LEAR, B. J. – TB07 LEE, C. J. – MJ09 LEE, G. W. – TF15 LEE, H. D. – MF03, TB02 LEE, J. S. – RB04, RB05 LEE, L. C. – WI15 LEE, S. K. – TF15 LEE, S. W. – TF15 LEE, T. J. – TH07 LEE, Y. – TI03 LEES, R. M. – TH11 LEFORESTIER, C. – RI05 LEGON, A. C. – WA03, RH11 LEHMANN, K. K. – MJ14, FD05, FD09 LEOPOLD, D. G. – RF14 LEOPOLD, K. R. – RC05, RC12 LESARRI, A. – MH07, MH08 LESCIUTE, D. – TG16 LESTER, M. I. – WJ09, FA10 LEUNG, H. O. – RC02, RC03 LEUNG, J. W. – RF06 LEWEN, F. – TH11 LEWERENZ, M. – RH13 LI, H. – WF12, FB01 LIEN, Y. – TG11 LIEVIN, J. – TD07 LINEBERGER, W. C. – MI12, TF03, WF02, WF03 LINK, J. J. – MF11 LINNARTZ, H. – RG10 LINTON, C. – MI02, RF03, RF04, RF09, RF11 LISY, J. M. – MG08, RA07 LITMAN, J. – FD07, FD10 LIU, A. – RF05 LIU, C. – MF03, TB02 LIU, J. – MI11, TJ01, TJ02, WH06, WJ10 LIU, X. – FD04 LIU, Y. – RD04 LLENDAL, H. M. – MH11, TC11 LOBUE, J. M. – TA10 LOCK, M. – TA12 LOCKE, R. J. – TG14 LOMBARDI, J. R. – FA08 LONG, D. A. – RD09, RD10 LOOCK, H. – FD07, FD10 LOONEY, L. W. – WI05 LOPEZ, G. V. – TJ11 LORD, S. D. – TH12 LOVAS, F. J. – MH01, WI05, RG04 LUO, P. – TG11 LYNCH, P. – WI08 LYNCH, W. B. – MI14 LÓPEZ, J. C. – MH12, TA01, TA02, TA03, RC08 M MA, Q. – RI04, RI05 MA, W. – TD08 MACKO, P. – TD06, TD07 MAJERZ, I. – RC09 MAKRIS, M. – MJ06 MANCERON, L. – TC02, TG04, TG05 MANDON, J. – TG01, TG02 MANNEY, G. – TI09 MANZANARES, C. E. – MJ10, TD10, RD08 MARCUM, J. C. – TF02, RB11 MARGULES, L. – TC10 MARGULÈS, L. – MH11, MH14, TC11, RH03 MARIS, A. – TA06, RC13, RH06 MARSHALL, M. D. – RC02, RC03 MARTIN, J. P. – WF02 MARTINEZ, R. Z. – WG11 MARTINEZ, T. J. – RE01 MASSICK, S. M. – FD02 MATA, I. P. S. – TA01 MATA, S. – TA03, RC08 MATSIKA, S. – WJ09, RE02, RE07 297 MATSUSHIMA, F. – TC04 MATYUSHENKO, V. I. – TE01 MAUL, C. – RI09 MAURER, J. – TJ10 MAY, T. – TG06 MAYORKAS, N. – WG12 MCBANE, G. C. – WF14 MCCAFFREY, J. G. – MJ08 MCCALL, B. J. – MA03, TE04, TE05, TE06, WH02, WI05, WI09, WI10, WI11, FD03, FD06 MCCARTHY, M. C. – TE10, TE11, WI06, WI14, WI16, RC01, RG08, RH13 MCCOY, A. B. – MG01, MG03, MI13, TF03, WF02, WF03, WF10, WF11, RJ03, RJ04, FA10 MCCUNE, D. W. – RC02 MCELCHERAN, C. – TI09 MCGUIRE, B. A. – WI11 MCKELLAR, A. R. W. – MG11, TC01, TG07, RA01, RA02, RA03, RA04, RA05 MEDINA, D. – RD04 MEDVEDEV, I. R. – TC09, TI10, TI11, WF06, WF07, WH04, WH05 MEERTS, W. L. – TF08, TF09, WJ02, WJ03 MEHROTRA, S. C. – FC10 MEIJER, G. – TJ10, WF05 MELANDRI, S. – TA06, RC13, RH06 MELLAU, G. C. – RI07 MELLON, D. – TD03 MELNIK, D. G. – WJ10, RD05 MELO, S. – RI10 MENTEN, K. M. – TC08, TH01, TH11, WI06 MERER, A. J. – TJ03 MERKE, I. – RH03 MERKT, F. – MI05, MI11, TB04, TJ01, TJ02, WH06, RH02 MERRITT, J. M. – MI03, MI09, MI10, TI07, TJ12 MESHKOV, V. V. – MI08 METSÄLÄ, M. – TD05 MICHAUD, J. M. – TB04 MIDDLETON, C. T. – RE05 MILLER, B. J. – WG05 MILLER, C. E. – RD09, RD10, RI12 MILLER, E. M. – MI12, WF03 MILLER, T. A. – TF08, TF09, TF13, TJ08, WJ10, RD05 MILLS, A. A. – TE06, WH02 MINITTI, M. P. – FB02 MITCHELL, J. – RI09, RJ05, RJ06 MLADENOVIC, M. – RH13 MOAZZEN-AHMADI, N. – MG11, RA01, RA02, RA03, RA04, RA05, RG16 MOLLNER, A. K. – WJ05 MONTENEGRO, M. – RF07 MONTGOMERY JR., J. A. – TA08 MOORE, C. B. – WJ10 MOORE, L. E. – WI11 MORALES-CUETO, R. – RD04 MORGAN, P. J. – TB05, TJ13 MORIWAKI, Y. – TC04 MORONG, C. P. – TE02 MORRISON, A. – MJ02 MOTIYENKO, R. – MH11, MH14, TC11 MROZIK, M. – RJ12 MUCKERMAN, J. T. – RJ09 MUCKLE, M. – MH08 MUCKLE, M. T. – MG04, MG05, MH01, TA05, TA09, WI06, RC11, RH08 MUKARAKATE, C. – WF01 MUKHERJEE, M. – TJ14, TJ15 MUKHOPADHYAY, A. – TJ14 MURRAY, C. – WJ09 MÄDER, H. – MH02, RH01 MÜLLER, C. – MF05 MÜLLER, C. W. – MF03, MF06, TB02, TB10, WG13 MÜLLER, H. S. P. – TC08, TC09, TH11, WH07 N NAHAR, S. N. – RF07 NAHON, L. – RG11 NAKAJIMA, M. – TJ09 NAU, P. – TD01 NAUTA, K. – TJ09 NEESE, C. – TC09 NEESE, C. F. – TA12, TI10, TI11, WH04, WH05 NEILL, J. – MH08 NEILL, J. L. – MG04, MG05, MH01, TA04, TA05, TA09, WI06, RC11, RH07, RH08 NELSON, D. D. – TG14 NEMCHICK, D. J. – TA12 NESBITT, D. J. – TF06, TF07, TF10, TF11 NEST, S. V. – MH09 NEUMARK, D. M. – MA02 NEVO, I. – TJ10, WF05 NEVRLÝ, V. – TI04 NEWBY, J. J. – MF03, TB02, TB09 NG, C. Y. – TF14 NICELY, A. L. – RA07 NIELSEN, J. H. – TJ10, WF05 NIMLOS, M. R. – MJ12 NIX, M. G. D. – WG13 NOUR, E. – FB08 NOVICK, S. E. – RH04, RH12 NUGENT, E. – RI12 O O’BRIEN, J. J. – RF01, RF02, RF08 O’BRIEN, L. C. – RF01, RF02, RF08 O’DONNELL, B. A. – FA10 O’DONNELL, D. M. – RB07 OBENCHAIN, D. A. – MH10, RH08 OHASHI, N. – TA10, RG15 OJHA, K. S. – FC09 OKA, T. – TE02, WI08, WI09, RG05 OKUMURA, M. – TF13, TI01, WJ11, RD02, RD09, RD10 OLESCHUK, R. D. – FD07 OLIAEE, J. N. – MG11, RA01, RA02, RA03, RA04, RA05 OLIVUCCI, M. – WJ06, WJ07 ONASCH, T. B. – RD06 OOMENS, J. – RB10, RG11 ORPHAL, J. – TD04, RI02 ORR-EWING, A. J. – TD02, TD03, RD07 ORTIGOSO, J. – FA05 OSTHOFF, A. A. – TA09 P PACIOS, L. F. – FA05 PANCHENKO, Y. N. – MG12, WG08 PANDEY, P. – MG06 PANG, H. F. – RF05, RF06 PARK, G. B. – RH07 PARSON, R. – WF03 PATE, B. H. – MG04, MG05, MH01, MH08, TA04, TA05, TA09, WI06, RC11, RH07, RH08 PAULSON, L. O. – MJ05 298 PEARSON, J. C. – TC06, TC07, TH03, TH06, TH09, TH10, TH12, TH13, WH08, WH09, WH10, WH12, WH13 PEEBLES, R. A. – MH10, TA09, RH08 PEEBLES, S. A. – MH10, TA09, RH08 PENA, I. – TA02, RC08 PERER, M. – RF15 PERERA, M. – TE06, WH02 PEREZ, C. – TA01, TA03 PEREZ-DELGADO, Y. – TD10, RD08 PERRIN, A. – TD07, TI04, RH03, RI06, RI07 PERRY, D. S. – MG04, MG05, FB04 PETERS, W. K. – WJ01 PETIT, A. S. – RJ03 PETRIGNANI, A. – TE03 PFLÜGL, C. – TG03 PICKETT, H. M. – TH06, WH12, RD09 PICQUÉ, N. – TG01, TG02 PIFRADER, A. – MI04 PILLSBURY, N. R. – MF05, MF06 PINO, T. – RG09 PIRALI, O. – TC02, TC10, TG04, TG05, RG11 PITICCO, L. – MI05 PITZER, R. – RF07 PITZER, R. M. – MI13, RJ12 PLUMMER, G. M. – TI10 PLUSQUELLIC, D. F. – MH01 POLFER, N. C. – RB10 POLYANSKY, O. L. – FC04 POTAPOV, A. V. – MJ13 POUCKE, P. V. – TD06 PRACNA, P. – TI04 PRADHAN, A. K. – RF07 PRATT, D. W. – TA04, TB01, TB05, TB06, TJ13, WJ02, WJ03, RC11, FA11 PRENDERGAST, C. – MJ08 PRESTON, T. J. – WF04 PSZCZÓLKOWSKI, L. – MH02 PUDLIK, T. – RC02 PULLIAM, R. L. – RH09, FC01, FC11 PUN, R. C. – RD05 PUZZARINI, C. – FA09, FC12 Q QUACK, M. – MG07, WG04, RJ02 QUAN, D. – WI07 R RAMIREZ, S. – WI02 RAPHELT, A. – MH13 RASTON, P. L. – MJ03, WF09 RAUNHARDT, M. – TJ01, TJ02, RH02 RAY, S. E. – WF10 REDDY, K. P. J. – FB09 REED, B. – TF14 REED, C. R. – MF09 REED, Z. D. – MG10 REICHARDT, C. – MF12 REID, S. A. – TF05, WF01 REINHARDT, S. – TE03 REISLER, H. – WA04, WJ05 RELPH, R. – MG01 REMIJAN, A. J. – MH01, TH02, WI05, WI06, RG04 RICE, F. – RG01 RICKS, A. M. – MG09, MG10, RA08 RINSLAND, C. P. – RI14 RITCHEY, A. M. – WI04 RITCHIE, G. A. D. – TD02 RIZOPOULOS, A. – TD06 ROBERTS, M. A. – TF06, TF07, TF10, TF11 ROBITAILLE, T. – WI02 RODRIGO, C. P. – MF05, MF06, TB09 ROHRDANZ, M. A. – RJ10 ROMANESCU, C. – TI06, WI15 ROMANINI, D. – RD03 ROMANO, N. C. – MJ09 ROSCIOLI, J. R. – TJ13 ROSENWAKS, S. – WG12 ROSS, A. J. – MI02, MI15 ROSS, S. C. – WF06, WF07 ROTGER, M. – RH03 ROTHMAN, L. S. – RI01 ROUZIÈRES, M. – TG04, TG05 ROY, P. – TC02, TC10, TG04, TG05, FB01 RUPPER, P. – TF08, TF09 RUTH, A. A. – TD04 S SABLINSKAS, V. – TG16, TI05 SALAMA, F. – TC05 SALB, K. N. – RC04 SALUMBIDES, E. J. – MI11 SAMANTA, A. K. – MG06 SAMS, R. L. – RI13, RI14 SANZ, M. E. – TA01, TA03 SARI, L. – WG09 SATO, A. – TA10 SAVAGE, C. – TF06 SAVJI, N. – RC02 SAXTON, N. L. – MJ09 SCHAEFER III, H. F. – TE11 SCHINKE, R. – WF14 SCHLEMMER, S. – MJ13, TC08, TH11, WH07, FC06 SCHMIDT, T. W. – TJ09 SCHMITT, M. – WJ02, WJ03 SCHULTHEIS, M. – WI02 SCHWENKE, D. W. – TH07 SCHÄFER, M. – MI05, TJ01, TJ02, RH02 SEARS, T. – TJ05 SEARS, T. J. – TF04, TF05, TJ11 SEBREE, J. A. – TB03 SECHLER, T. D. – WJ09 SEDES, G. – MH03 SEDO, G. – RC12 SELLGREN, K. – WI02 SELVAM, L. – TB08 SEMBA, Y. – TJ07 SENENT, M. L. – FA06 SERDYUCHENKO, A. – RI08 SHALHOUT, F. – MF07 SHARP-WILLIAMS, E. N. – TF07, TF10, TF11 SHEFFER, Y. – WI04 SHEN, L. – WF14, RE10 SHEPS, L. – MI12, WF03 SHI, Y. J. – MI06, RB01 SHIPMAN, S. T. – MH08, TA05 SHUBERT, V. A. – TB10 SHY, J. – TG11 SILLER, B. M. – FD03 SIMPSON, G. J. – FB06 SINGER, S. J. – FB11 SINGH, M. K. – FA07 SINGH, P. C. – WF14 SINGH, S. C. – FC09 SINGH, V. B. – RJ11, FA07 SIZOV, V. D. – TE01 SLANGER, T. G. – WI15 SLITER, R. – MJ06 SMITH, E. R. – WJ01 SMITH, G. P. – TI06 299 SMITH, H. A. – WI02 SMITH, M. A. H. – RI13 SNYDER, L. E. – WI05 SODERGREN, A. H. – WG05 SOLOVEICHIK, P. – FA10 SONG, Y. – RE09 SPEZZANO, S. – WI16 SPRECHER, D. – TJ01, TJ02 STANTON, J. – WJ11, RB09, RD02 STANTON, J. F. – TI02, RE08 STAPELFELDT, H. – TJ10, WF05 STARCK, T. – RH01 STARIKOVA, E. – TG12 STEBER, A. L. – MH10, RH08 STEEVES, A. H. – RH07 STEILL, J. – RB10 STEIMLE, T. C. – RF04, RF09, RF10, RF13 STEVENS, J. A. – MF11 STEWART, J. T. – FD06 STIDHAM, H. D. – MH10 STIOPKIN, I. V. – MF07 STOHNER, J. – RJ02 STOLOVY, S. – WI02 STOLYAROV, A. V. – MI08 STRAHAN, S. – TI09 STRAZDAITE, S. – TI05 STRONG, K. – RI10 STUTZKI, J. – WH07 STŘIŽÍK, M. – TI04 SU, C. – RE04 SUENRAM, R. D. – MH07, MH08, TA05 SUITS, A. G. – WF14, RE10 SUMIYOSHI, Y. – FC03 SUMNER, M. C. – RG01 SUN, M. – FC07, FC08 SUNAHORI, F. – TJ06 SUNAHORI, F. X. – TJ04 SUNG, K. – RI11, RI12 SURIN, L. A. – MJ13 TAO, C. – TF05, WF01 TARNOVSKY, A. N. – WJ06 TASINATO, N. – TG10 TATAMINTANI, Y. – TA10 TATCHEN, J. – WJ02 TAYLOR, J. R. – TI09 TENENBAUM, E. D. – WI03 TEYSSIER, D. – TH12 THADDEUS, P. – TE10, TE11, WI06, WI14, WI16, RC01, RG07, RG08, RH13 THAM, K. S. – TJ03 THIEL, W. – FC06 THOMAS, J. A. – TB01, TB06 THOMAS, P. – RD05 THOMAS, P. S. – TJ08 THOMPSON, M. A. – WF03 THOMPSON, R. I. – MI06 THOMPSON, W. E. – TE07, TF12 THORPE, M. J. – FD01 THORWIRTH, S. – TE10, WI06, RC01 TIMMERS, H. – TI06 TING, W. – TG11 TIPPING, R. H. – RI04, RI05 TOKARYK, D. – RF11 TOKARYK, D. W. – RF03 TOM, B. A. – WI11 TOON, G. C. – TI09 TOTH, R. A. – RI11, RI12 TRETYAKOV, M. Y. – FC04 TRIPATHI, G. N. R. – RB07 TROY, T. P. – TJ09 TRUEMAN, T. – RH01 TSUNEKAWA, S. – RG15 TUBERGEN, M. J. – MH15 TUDORIE, M. – MH03, TC10 TURRO, C. – MF09 TUYTEREV, V. G. – TG12 TWAGIRAYEZU, S. – MG04, MG05 U T TACHI, H. – RG15 TAGUE, T. J. – TG03 TAKAGI, K. – TC04 TAKEMATSU, K. – TF13, TI01, WJ11, RD02 TAM, W. S. – RF06 TANAKA, Y. – TA11 TANDY, J. D. – RF12 TANG, S. – RC09 TANJAROON, C. – TA07 UBACHS, W. – MI11 UPADHYA, D. M. – FA07 UZUYAMA, T. – TA11 V VAIDA, V. – WG05 VALENZUELA, E. A. – TA06 VAQUERO, V. – TA01, TA02, RC08 VARMA, R. M. – TD04 VARNER, M. E. – TI02 VASILATOU, K. – TB04 VASILIOU, A. – MJ12, TF14 VASILYEV, V. – TB08, TB08 VAUGHAN, S. – TD04 VAUTHEY, E. – WJ07 VEGA-TORIBIO, A. – MH07 VENTRILLARD-COURTILLOT, I. – RD03 VERHEYEN, L. – WI06 VERVLOET, M. – TG04, TG05, RG11 VIGGIANO, A. A. – MG01 VILESOV, A. F. – MJ06 VILLA, M. – FA06 VILLARROEL, O. J. – RB06, FB05 VISSERS, G. W. M. – WF10 VOGELHUBER, K. M. – TF03 VOGT, R. A. – MF12 VÁZQUEZ, J. – TI02 W WADA, R. – RD07 WAECHTER, H. – FD07 WAGNER, G. – TG09 WALKER, K. A. – TI09 WALKER, N. R. – RH11 WALTERS, A. – TC08, WH12 WANG, F. – TB08 WANG, H. – TE02, RF04, RF09, RF13 WANG, J.- G. – RF12 WANG, L. – MF10 WANG, P. – TG03 WANG, Y. – TI09 WANG, Z. – TF04, TF05, TJ05 WEAVER, S. L. W. – RG01, RG06 WEBER, J. M. – TF01, TF02, RB11 WEBER, M. – RI08 WEBER, P. – MF02 WEBER, P. M. – FB02 WEDDLE, G. H. – WG02, WG03 WEERAMAN, C. – MF07 WEI, J. – TJ05, TJ06 WEIGUM, N. – TI09 WENTHOLD, P. G. – RB08 WERNET, M. – TG14 WHEATLEY, D. – RH11 WHITE, A. R. – TG15 WHITTEMORE, S. – RF08 WIJERATNE, N. R. – RB08 WIJNGAARDEN, J. V. – MH09, TC03 300 WILKE, J. J. – TE11 WILLEY, D. R. – RC04 WILLIAMS, C. F. – FA02 WILLNER, H. – TI04, RH03, RI06 WILSON, K. R. – WI15 WINNEWISSER, B. P. – WF06, WF07, RH14 WINNEWISSER, M. – TC09, WF06, WF07, RH14 WLODARCZAK, G. – MH14 WOLF, A. – TE03 WONG, B. M. – MI07 WOOD, E. C. – RD06 WOOD, T. J. – WI11 WOODS, R. C. – TA06 WOON, D. E. – RG14, RJ07, RJ08 WORMHOUDT, J. – TG14, RD06 WREN, S. W. – TF03 WU, L. – TE09 X XIANG, B. – TD09 XIAO, H. – WI08 XIN, J. – TF04 XING, X. – TF14 XU, L. – TH11, WH08 XU, X. F. – RE03 XU, Y. – FD04 Y YABUGUCHI, H. – RA06 YAMADA, K. M. T. – FC06 YAMADA, Y. – RA06, RA11 YANG, D. – TE09, RB04, RB05 YANG, J. – TJ04, TJ06 YANG, Y. – MF10 YE, J. – RF06, FD01 YONEZU, T. – TC04 YOON, Y. H. – FB03 YOSHIDA, K. – TJ07 YOSHIDA, Y. – TI09 YOUNG, J. W. – TB01, TB06, FA11 YU, H. – WI12 YU, S. – TC06, TC07, TH06, TH13, WH10, WH11, WH12, WH13 YURCHENKO, S. N. – FC06 YURTSEVEN, H. – WG14 Z ZACK, L. N. – RG03, RH10, FC01, FC02 ZANG, C. – MF11 ZANNI, M. T. – WG06 ZARE, R. N. – FD08 ZELINGER, Z. – TI04 ZHANG, B. – RE10 ZHANG, C. – TE09 ZHANG, G. – TJ03 ZHANG, J. – WH03, RD04, RE09 ZHANG, L. – MF10 ZHANG, X. – TF14 ZHENG, X. – RE09 ZHONG, D. – MF10, MF11, FB11 ZHOU, W. – RE09 ZHU, C. – TD09 ZHU, L. – TD09 ZHUANG, X. – RF04, RF13 ZILBERG, S. – RE03 ZIURYS, L. M. – WI03, RC01, RG02, RG03, RH09, RH10, FC01, FC02, FC05, FC07, FC08, FC11 ZMUIDZINAS, J. – RG01 ZWIER, T. S. – MF03, MF05, MF06, TB02, TB03, TB09, TB10, WG13 301 The Symposium expresses its appreciation to Elsevier for its support of the Journal of Molecular Spectroscopy Special Lecture 302 The Symposium expresses its appreciation to COHERENT for subsidizing the cost of the picnic 1080 Lasers for Spectroscopy. 1030 785 700 680 660 CUBE™ Compass™ (Diode Lasers) Sapphire™ (Diode-Pumped Solid-State Lasers) 640 635 561 Genesis™ (Optically Pumped Semiconductor Laser) MBR (CW Tunable Lasers) Chameleon™ (Continuous Tuning, fs Pulses) 532 488 460 445 Coherent is the expert in more types of CW, pulsed and quasi-CW laser technology than any other company. This includes our unique and scalable OPSL (Optically Pumped Semiconductor Laser) technology that can be designed to produce any target wavelength or power level in the IR, visible, and near-UV. And because we are vertically integrated, with the complete control over quality at every level, our lasers also deliver the industry’s highest reliabilty and longest lifetimes. To learn more about the most comprehensive and capable lasers for spectroscopy available, visit our website at www.Coherent.com. 405 375 355 tech.sales@Coherent.com www.Coherent.com toll free: (800) 527-3786 phone: (408) 764-4983 Benelux +31 (30) 280 6060 China +86 (10) 6280 0209 France +33 (0)1 6985 5145 Germany +49 (6071) 968 204 Superior Reliability & Performance Italy +39 (02) 34 530 214 Japan +81 (3) 5635 8700 Korea +82 (2) 460 7900 UK +44 (1353) 658 833 303 The Symposium thanks Quantel for its support in the memory of Ralph Swaine for the Women’s Lunch 304 The Symposium expresses its appreciation to Virginia Diodes for subsidizing the cost of the coffee 305 POZNAN2010 The 21st International Conference on High Resolution Molecular Spectroscopy Poznań, Poland, September 7-11, 2010 The subjects covered at this meeting are largely identical to those covered at the Ohio State University Symposia on Molecular Spectroscopy. Please check the conference website http://www.chem.uni-wuppertal.de/conference/ for up-to-date information or contact the chairman of the local organizing committee Prof. Marek Kr eglewski ( Department of Chemistry Adam Mickiewicz University PL-60-780 Poznań Poland Tel/Fax: +48 (0) 61 829 1387 E-mail: mkreg@amu.edu.pl