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Title: Infrared Spectroscopy of the Entrance Channel Complex Formed Between the Hydroxyl Radical and Methane in Helium Nanodroplets

Journal Article · · Journal of Physical Chemistry. A, Molecules, Spectroscopy, Kinetics, Environment, and General Theory

Here, the entrance channel complex in the exothermic OH + CH4 → H2O + CH3 reaction has been isolated in helium nanodroplets following the sequential pick-up of the hydroxyl radical and methane. The a-type OH stretching band was probed with infrared depletion spectroscopy, revealing a spectrum qualitatively similar to that previously reported in the gas phase, but with additional substructure that is due to the different internal rotation states of methane (jCH4 = 0, 1, or 2) in the complex. We fit the spectra by assuming the rotational constants of the complex are the same for all internal rotation states; however, subband origins are found to decrease with increasing jCH4. Measurements of deuterated complexes have also been made (OD–CH4, OH–CD4, and OD–CD4), the relative linewidths of which provide information about the flow of vibrational energy in the complexes; vibrational lifetime broadening is prominent for OH–CH4 and OD–CD4, for which the excited OX stretching state has a nearby CY4 stretching fundamental (X, Y = H or D).

Research Organization:
Univ. of Georgia, Athens, GA (United States)
Sponsoring Organization:
USDOE Office of Science (SC), Basic Energy Sciences (BES)
Grant/Contract Number:
SC0008086
OSTI ID:
1409064
Journal Information:
Journal of Physical Chemistry. A, Molecules, Spectroscopy, Kinetics, Environment, and General Theory, Vol. 121, Issue 40; ISSN 1089-5639
Publisher:
American Chemical SocietyCopyright Statement
Country of Publication:
United States
Language:
English

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Cited By (2)

Infrared spectroscopy in superfluid helium droplets journal December 2018
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