Vibrational relaxation of CO (n = 1) in collisions with H/sub 2/. II. Influence of H/sub 2/ rotation

Journal Article · Tue Jan 01 04:00:00 EST 1985 · J. Chem. Phys.; (United States)

OSTI ID:6212926

Bacic, Z; Schinke, R; Diercksen, G H.F.

Vibrational relaxation of CO (n/sub 1/ = 1) in collision with ortho, para H/sub 2/ is studied quantum mechanically, with the rotational degree of freedom of H/sub 2/ included. This represents extension of our earlier study (Ref. 11, J. Chem. Phys. 81, 0000 (1984)), where H/sub 2/ was treated as a structureless particle. The potential surface, described in detail in Ref. 11, consists of a SCF part, which includes explicitly the variation with the CO bond distance, and a damped long range dispersion contribution. The relaxation cross sections are calculated within the infinite order sudden approximation (IOSA) for CO rotation and within the coupled states approximation (CSA) for H/sub 2/ rotation. Many of the trends clearly present in the cross sections can be understood in terms of the distorted wave approximation (DWA). The calculated relaxation rates in para H/sub 2/ agree well (within a factor of 2) with the experimental results. However, judging from a limited number of calculated cross sections for relaxation in ortho H/sub 2/, the ortho H/sub 2/ relaxation rates would be comparable in magnitude to the para rates, in disagreement with experiment. Extensive comparison is made with the work of Poulsen and Billing (Ref. 12) and a number of significant, even qualitative differences regarding magnitude of some simultaneous CO vibrational and H/sub 2/ rotational transitions are discussed.

• Research Organization: MPI fuer Stroemungsforschung, 3400 Goettingen, West Germany
• OSTI ID: 6212926
• Journal Information: J. Chem. Phys.; (United States), Journal Name: J. Chem. Phys.; (United States) Vol. 82:1; ISSN JCPSA
• Country of Publication: United States
• Language: English

Related Subjects

640304* -- Atomic
Molecular & Chemical Physics-- Collision Phenomena
74 ATOMIC AND MOLECULAR PHYSICS
CARBON COMPOUNDS
CARBON MONOXIDE
CARBON OXIDES
CHALCOGENIDES
COLLISIONS
ELEMENTS
ENERGY LEVELS
EXCITED STATES
HYDROGEN
MECHANICS
MOLECULE COLLISIONS
MOLECULE-MOLECULE COLLISIONS
NONMETALS
OXIDES
OXYGEN COMPOUNDS
QUANTUM MECHANICS
RELAXATION
VIBRATIONAL STATES