Direct Frequency Comb Measurement of OD + CO -> DOCO Kinetics

Author(s): B. J. Bjork, T.Q. Bui, O. H. Heckl, P. B. Changala, B. Spaun, P. Heu, C. Deutsch, G. D. Cole, M. Aspelmeyer, M. Okumura, J. Ye

Journal: Science

Volume: 354

Page(s): 444-448

Year: 2016

DOI Number: 10.1126/science.aag1862

Link: Link to publication

Abstract:

The kinetics of the OH + CO reaction, fundamental to both atmospheric and combustion chemistry, are complex due to the formation of the HOCO intermediate. Despite extensive studies on this reaction, HOCO has not been observed at thermal reaction conditions. Exploiting the sensitive, broadband, and high-resolution capabilities of time-resolved cavity-enhanced direct frequency comb spectroscopy, we observe OD + CO reaction kinetics with the detection of stabilized trans-DOCO, the deuterated analogue of trans-HOCO, and its yield. By simultaneously measuring the time-dependent concentrations of both trans-DOCO and OD species, we observe unambiguous low-pressure termolecular dependence on the reaction rate coefficients for both N2 and CO bath gases. These results confirm the HOCO formation mechanism and quantify its yield.

Note: Issue 6311

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