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arXiv · 1002.1572

When diffraction rules the stereodynamics of rotationally inelastic collisions

Mikhail Lemeshko·Pablo G. Jambrina·Marcelo P. de Miranda·Bretislav Friedrich
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Abstract

Following upon our recent work on vector correlations in the Ar-NO collisions [PCCP 12, 1038 (2010)], we compare model results with close-coupling calculations for a range of channels and collision energies for the He-NO system. The striking agreement between the model and exact polarization moments indicates that the stereodynamics of rotationally inelastic atom-molecule collisions at thermal energies is governed by diffraction of matter waves from a two-dimensional repulsive core of the atom-molecule potential. Furthermore, the model polarization moments characterizing the He-NO, He-O$_2$, He-OH, and He-CaH stereodynamics are found to coalesce into a single, distinctive pattern, which can serve as a "fingerprint" to identify diffraction-driven stereodynamics in future work.

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Mikhail Lemeshko, Pablo G. Jambrina, Marcelo P. de Miranda, Bretislav Friedrich. 2010-03-26. When diffraction rules the stereodynamics of rotationally inelastic collisions. https://doi.org/10.1063/1.3386530

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