Collision-induced rotovibrational spectra of H/sub 2/-He pairs from first principles

Journal Article · Thu Jan 15 04:00:00 EST 1987 · Phys. Rev. A; (United States)

DOI:https://doi.org/10.1103/PhysRevA.35.632· OSTI ID:7020245

Frommhold, L; Meyer, W

A previous study of the collision-induced dipole moment has treated the H/sub 2/-He complex as a molecule in self-consistent-field and size-consistent coupled-electron-pair approximation (Meyer and Frommhold, Phys. Rev. A 34, 2771 (1986)). Based on that work, the vibrational dipole transition elements associated with the fundamental band (v = 0..-->..v' = 1) are obtained as functions of separation R of the collisional pair for the isotropic and anisotropic overlap induction components (lambdaL = 01 and 21), and the quadrupole- and hexadecapole-induced parts (lambdaL = 23 and 45). From these induced dipole components and Meyer, Hariharan, and Kutzelnigg's isotropic part of the ab initio potential surface, we compute in the (forbidden) fundamental band of hydrogen the collision-induced absorption spectra of the collisional complex of hydrogen (H/sub 2/) and helium from an exact quantum formalism. Both the shape of the computed spectral profiles and the theoretical absolute intensity agree closely with existing measurements at temperatures from 18 to 300 K. The fact that these spectra, and presumably the analogous overtone and ''hot'' (v>0) bands of the H/sub 2/-He complex which are not known from measurements, can be accurately obtained from basic principles is significant for research related to the atmospheres of the giant planets and late-type stars.

• Research Organization: Physics Department, University of Texas at Austin, Austin, Texas 78712-1081
• OSTI ID: 7020245
• Journal Information: Phys. Rev. A; (United States), Journal Name: Phys. Rev. A; (United States) Vol. 35:2; ISSN PLRAA
• Country of Publication: United States
• Language: English

Related Subjects

640302* -- Atomic
Molecular & Chemical Physics-- Atomic & Molecular Properties & Theory
74 ATOMIC AND MOLECULAR PHYSICS
ABSORPTION SPECTRA
ATMOSPHERES
ATOM COLLISIONS
ATOM-MOLECULE COLLISIONS
BOUND STATE
COLLISIONS
COMPLEXES
ELEMENTS
ENERGY LEVELS
EXCITED STATES
FLUIDS
GASES
HELIUM
HYDROGEN
HYDROGEN COMPLEXES
MOLECULE COLLISIONS
NONMETALS
PLANETARY ATMOSPHERES
RARE GASES
ROTATIONAL STATES
SELF-CONSISTENT FIELD
SPECTRA
VIBRATIONAL STATES