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arXiv · 1806.07455

Unravelling the stereodynamics of cold HD-H2 collisions

James F. E. Croft·Naduvalath Balakrishnan·Meng Huang·Hua Guo
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Abstract

Measuring inelastic rates with partial wave resolution requires temperatures close to a Kelvin or below, even for the lightest molecule. In a recent experiment Perreault et al. [1] studied collisional relaxation of excited HD molecules in the v = 1, j = 2 state by para- and ortho-H2 at a temperature of about 1 K, extracting the angular distribution of scattered HD in the v = 1,j = 0 state. By state-preparation of the HD molecules, control of the angular distribution of scattered HD was demonstrated. Here, we report a first-principles simulation of that experiment which enables us to attribute the main features of the observed angular distribution to a single L = 2 partial-wave shape resonance. Our results demonstrate important stereodynamical insights that can be gained when numerically-exact quantum scattering calculations are combined with experimental results in the few-partial-wave regime.

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James F. E. Croft, Naduvalath Balakrishnan, Meng Huang, Hua Guo. 2018-06-19. Unravelling the stereodynamics of cold HD-H2 collisions. https://doi.org/10.1103/physrevlett.121.113401

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