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, D. Follman, C. Deutsch, G. D. Cole, M. Aspelmeyer, M. Okumura, J. Ye
Abstract

The kinetics of the hydroxyl radical (OH) + carbon monoxide (CO) reaction, which is fundamental to both atmospheric and combustion chemistry, are complex because of the formation of the hydrocarboxyl radical (HOCO) intermediate. Despite extensive studies of this reaction, HOCO has not been observed under thermal reaction conditions. Exploiting the sensitive, broadband, and high-resolution capabilities of time-resolved cavity-enhanced direct frequency comb spectroscopy, we observed deuteroxyl radical (OD) + CO reaction kinetics and detected stabilized trans-DOCO, the deuterated analog of trans-HOCO. By simultaneously measuring the time-dependent concentrations of the trans-DOCO and OD species, we observed unambiguous low-pressure termolecular dependence of the reaction rate coefficients for N-2 and CO bath gases. These results confirm the HOCO formation mechanism and quantify its yield.

Organisation(s)
Quantum Optics, Quantum Nanophysics and Quantum Information
External organisation(s)
National Institute of Standards and Technology, Gaithersburg, University of Colorado, Boulder, Thorlabs Inc., Crystalline Mirror Solutions GmbH, California Institute of Technology (Caltech)
Journal
Science
Volume
354
Pages
444-448
No. of pages
5
ISSN
0036-8075
DOI
https://doi.org/10.1126/science.aag1862
Publication date
10-2016
Peer reviewed
Yes
Austrian Fields of Science 2012
103006 Chemical physics, 103021 Optics
Keywords
Portal url
https://ucrisportal.univie.ac.at/en/publications/direct-frequency-comb-measurement-of-od--codoco-kinetics(9d35ebf3-dc73-4921-9a5a-ff6a2e62080e).html