Coupled channel study of rotational excitation of H$sub 2$ by Li$sup +$ collisions
Integral cross sections for rotatlonal excitation of H/sub 2/ by Li/sup +/ im pact have been computed in a coupled channel formalism for the energy range 0.05-0.5 eV. Computational results are reported for the rigid rotator, energy corrected'' rigid rotator, and vibrating rotator models (the latter using accurate numerical vibrational functions of the Kolos-Wolniewicz potential including adiabatic connection). The energy corrected'' model, which adjusts the energy levels of the rigid rotator to agree closely wlth the experimental levels of the diatomic molecule by inclusion of the centrifugal distortion term, affords a noticeable improvement over the usual rigid rotator approximation for H/ sub 2/ with no increase in computational effort. Comparison with the classical rigid rotator results of LaBudde and Bemstein STAJ. Chem. Phys. 59, 3687 (1973)! show reasonable agreement with the present rigid rotator cross sections retaining open channels only. Peaks are obtained in the partial integral cross section in the threshold region for the (a) 0 yields 2 transition (0.05 eV), (b) 0 yields 4 transition (0.15 ev), and (c) 0 yields 6 transition (0.3 ev). For 0 yields 4,6 excitations, indirect transitions make the dominate contribution to the cross sections. (auth) Further classical trajectory calculations of the rotational excitation of H/sub 2/ in collision with Li/sup +/ have been carried out in order to assess several alternative classical-quantal correspendence relationships. The results are compared with exact quantal cross sections computed for the same model system by Lester and Schaefer. (auth)
- Research Organization:
- IBM Research Laboratory, San Jose, California 95193
- NSA Number:
- NSA-29-022321
- OSTI ID:
- 4345890
- Journal Information:
- J. Chem. Phys., v. 59, no. 7, pp. 3676-3686, Other Information: Orig. Receipt Date: 30-JUN-74
- Country of Publication:
- United States
- Language:
- English
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