Vibrational inelasticity in H₂ collisions with He and Li⁺

Thesis/Dissertation · Mon Sep 01 04:00:00 EDT 1975

DOI:https://doi.org/10.2172/4138375· OSTI ID:4138375

Raczkowski, Andrew Wesley ^[1]

---

1. Univ. of California, Berkeley, CA (United States)

The partially averaged version of classical S-matrix theory was applied to three-dimensional collisions of H₂ with He and Li⁺. For H₂- Li⁺, cross-sections for the de-excitation of H₂ from (n₁,j₁) = (1,0) to the ground vibrational manifold were computed at a total energy of 1.2 eV and compared to previously done coupled channel calculations of Schaefer and Lester. The agreement is very good. For H₂-He, the Kutzelnigg- Tsapline interaction potential was extended to small atom-diatom separations, the ab initio points were then fit to an analytic form, and cross sections for the de- excitation of H₂ from the states (n₁,j₁), n₁ = 1, j₁ = 0,2,4 to the ground vibrational manifold were computed at total energies of .9, 1.1, 1.3 and 1.5 eV. For comparison, coupled channel calculations were also performed on the system at the same energies. The agreement was poorer than in the H₂-Li⁺ case, for identifiable reasons. The cross sections were used to compute rate constants and relaxation times for the H₂-He system. Comparison of these results with the results of experiment and of other calculations shows good agreement, certainly within the expected errors.

• Research Organization: Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
• Sponsoring Organization: US Energy Research and Development Administration (ERDA)
• DOE Contract Number: W-7405-ENG-48
• NSA Number: NSA-33-008289
• OSTI ID: 4138375
• Report Number(s): LBL--3798
• Country of Publication: United States
• Language: English

Related Subjects

*HELIUM-- ATOM-MOLECULE COLLISIONS
*HYDROGEN-- ION-MOLECULE COLLISIONS
*LITHIUM IONS-- ION-MOLECULE COLLISIONS
74 ATOMIC AND MOLECULAR PHYSICS
CROSS SECTIONS
S MATRIX