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arXiv · 0906.0443

A model analysis of rotationally inelastic Ar + H$_2$O scattering in an electric field

Mikhail Lemeshko·Bretislav Friedrich
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Abstract

We develop an analytic model of thermal state-to-state rotationally inelastic collisions of asymmetric-top molecules with closed-shell atoms in electric fields, and apply it to the Ar--H$_2$O collision system. The predicted cross sections as well as the steric asymmetry of the collisions show at fields up to 150 kV/cm characteristic field-dependent features which can be experimentally tested. Particularly suitable candidates for such tests are the $0_{00} \to 2_{20}$ and $1_{01} \to 2_{21}$ channels, arising from the relaxation of the field-free selection rules due to the hybridization of $J$ states. Averaging over the $M'$ product channels is found to largely obliterate the orientation effects brought about by the field.

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Mikhail Lemeshko, Bretislav Friedrich. 2009-06-02. A model analysis of rotationally inelastic Ar + H$_2$O scattering in an electric field. https://doi.org/10.1021/jp9051598

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