Calculation of pressure broadening parameters for the CO-He system at low temperatures

Journal Article · Wed May 01 04:00:00 EDT 1985 · J. Chem. Phys.; (United States)

DOI:https://doi.org/10.1063/1.448710· OSTI ID:5892619

Green, S

Theoretical pressure broadening parameters were computed for the 0-1 and 1-2 rotational transitions of CO in He at very low temperatures and compared with the recent experimental measurements at 4.2 K. The interaction potential was taken from extensive SCF-CI calculations, molecular collision dynamics were described by essentially exact converged close coupling calculations, and pressure broadening cross sections were obtained from the collisional S matrices within the accurate Fano-Ben Reuven framework. Resonances at low collision energies give rise to an increase in the thermally averaged cross sections at low temperatures. Although previous calculations for this system at higher temperatures (77-300 K) were in good accord with experiment, at 4.2 K predicted values are about two times larger than experiment; possible sources of this discrepancy are discussed. 12 references.

• Research Organization: NASA, Goddard Institute for Space Studies, New York, NY
• OSTI ID: 5892619
• Journal Information: J. Chem. Phys.; (United States), Journal Name: J. Chem. Phys.; (United States) Vol. 82; ISSN JCPSA
• Country of Publication: United States
• Language: English

Related Subjects

640304* -- Atomic
Molecular & Chemical Physics-- Collision Phenomena
74 ATOMIC AND MOLECULAR PHYSICS
ATOM COLLISIONS
ATOM-MOLECULE COLLISIONS
CARBON COMPOUNDS
CARBON MONOXIDE
CARBON OXIDES
CHALCOGENIDES
COLLISIONS
ELEMENTS
ENERGY-LEVEL TRANSITIONS
FLUIDS
GASES
HELIUM
MOLECULE COLLISIONS
NONMETALS
OXIDES
OXYGEN COMPOUNDS
RARE GASES
RESONANCE