Rotational excitation of OH by H2: calculations in intermediate coupling
- 28 June 1983
- journal article
- Published by IOP Publishing in Journal of Physics B: Atomic and Molecular Physics
- Vol. 16 (12) , 2157-2168
- https://doi.org/10.1088/0022-3700/16/12/012
Abstract
The authors present the results of calculations of cross sections for the rotational excitation of OH by para-H2. The calculations are performed in the angular momentum coupling scheme appropriate to the OH radical, intermediate between Hund's cases a and b. Comparison with previous results, obtained in the case b limit, shows that the principal effect of the spin-orbit interaction is to reduce the asymmetries in the cross sections which lead to preferential excitation of a given component of a Lambda doublet. Nevertheless, the asymmetries remain large, and rotational excitation by H2 may be expected to play an important role in producing the maser emission from the Lambda doublets in the 2 Pi 3/2 ladder, observed in the interstellar medium.Keywords
This publication has 19 references indexed in Scilit:
- Rotationally inelastic collisions between a diatomic molecule in a2Π electronic state and a structureless targetThe Journal of Chemical Physics, 1982
- Rovibrational excitation of molecular hydrogen in collisions with helium atomsJournal of Physics B: Atomic and Molecular Physics, 1982
- Radial dependence of spin-orbit and Λ-doubling parameters in the X2Π ground state of hydroxylJournal of Molecular Spectroscopy, 1982
- Rovibrational excitation of molecular hydrogen by heliumJournal of Physics B: Atomic and Molecular Physics, 1982
- Rotational excitation of OH by H2at thermal energiesJournal of Physics B: Atomic and Molecular Physics, 1981
- Collisional excitation of OH by H2: transitions within the ground-state Λ doubletJournal of Physics B: Atomic and Molecular Physics, 1981
- The far-infrared Laser Magnetic Resonance Spectrum of the OH radicalJournal of Molecular Spectroscopy, 1981
- Collisional pumping of a-doublet transitions in CH and OH by H2 and HeChemical Physics Letters, 1979
- Coupled states cross sections for rotational excitation of H2CO by He impact at interstellar temperaturesThe Journal of Chemical Physics, 1977
- Collisional excitation of lambda doublet transitions in CH and OHThe Astrophysical Journal, 1976