69 th International Symposium on Molecular Spectroscopy Chirped

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69 th International Symposium on Molecular Spectroscopy Chirped Pulse Fourier Transform Microwave Spectroscopy in

69 th International Symposium on Molecular Spectroscopy Chirped Pulse Fourier Transform Microwave Spectroscopy in Pulsed Uniform Supersonic Flows Chamara Abeysekera, James M. Oldham, Baptiste Joalland, Kirill Prozument, Lindsay N. Zack, and Arthur G. Suits Department of Chemistry, Wayne State University G. Barratt Park and Robert W. Field Department of Chemistry, Massachusetts Instiute of Technology Ian R. Sims Institut de Physique de Rennes, Université de Rennes June 16, 2014

69 th International Symposium on Molecular Spectroscopy Reaction Dynamics • Gives a molecular-level understanding

69 th International Symposium on Molecular Spectroscopy Reaction Dynamics • Gives a molecular-level understanding of chemical reactivity • How a reaction proceeds • Predict outcomes Common techniques: state-selected REMPI velocity map imaging June 16, 2014

69 th International Symposium on Molecular Spectroscopy June 16, 2014 Reaction Dynamics For larger

69 th International Symposium on Molecular Spectroscopy June 16, 2014 Reaction Dynamics For larger and more complex systems: • Lack of isomer- and vibrational level-specific information • Unreliable branching ratios • Products not always able to be inferred

69 th International Symposium on Molecular Spectroscopy June 16, 2014 Chirped Pulse Fourier Transform

69 th International Symposium on Molecular Spectroscopy June 16, 2014 Chirped Pulse Fourier Transform Microwave Spectroscopy • Isomer and vibrational level specificity • Definitive identification of species • Broadband advantage

69 th International Symposium on Molecular Spectroscopy Instrumentation June 16, 2014

69 th International Symposium on Molecular Spectroscopy Instrumentation June 16, 2014

June 16, 2014 69 th International Symposium on Molecular Spectroscopy Spectrometer (“CPUF”) 26 –

June 16, 2014 69 th International Symposium on Molecular Spectroscopy Spectrometer (“CPUF”) 26 – 40 GHz 60 – 90 GHz

69 th International Symposium on Molecular Spectroscopy Spectrometer June 16, 2014

69 th International Symposium on Molecular Spectroscopy Spectrometer June 16, 2014

June 16, 2014 69 th International Symposium on Molecular Spectroscopy t = 10 ms

June 16, 2014 69 th International Symposium on Molecular Spectroscopy t = 10 ms x 5 v population 0 0. 09 1 0. 23 2 0. 56 3 0. 06 4 0. 06 Brouard et al. (2004) JCPA, 108, 7965 CP-FTMW-PUSF as a probe of nascent vibrational distributions t = 65 ms

69 th International Symposium on Molecular Spectroscopy 193 nm C 2 H 3 CN

69 th International Symposium on Molecular Spectroscopy 193 nm C 2 H 3 CN June 16, 2014 HC 3 N (v, J) + H 2

69 th International Symposium on Molecular Spectroscopy June 16, 2014 Conclusions and Future Directions

69 th International Symposium on Molecular Spectroscopy June 16, 2014 Conclusions and Future Directions • CPUF can be used to probe photochemistry • Nascent product vibrational distributions can be investigated • Bimolecular reactions next: – Cl + alkenes – Criegee intermediates and QOOH

69 th International Symposium on Molecular Spectroscopy June 16, 2014 SOCl + C H

69 th International Symposium on Molecular Spectroscopy June 16, 2014 SOCl + C H Conclusions and Future Directions 2 3 6 (analysis in progress)

69 th International Symposium on Molecular Spectroscopy Acknowledgements • Prof. Arthur G. Suits (WSU)

69 th International Symposium on Molecular Spectroscopy Acknowledgements • Prof. Arthur G. Suits (WSU) • Prof. Robert W. Field (MIT) • Prof. Ian R. Sims (Rennes) • Suits, Field, and Sims Groups June 16, 2014