Nonlocal theory of dissociative electron attachment to H₂ and HF molecules

Authors

Gordon A. Gallup, University of Nebraska-LincolnFollow
Y. [Yuanguang] Xu, University of Nebraska-Lincoln
Ilya I. Fabrikant, University of Nebraska-LincolnFollow

Date of this Version

4-1-1998

Comments

Published by American Physical Society. Phys. Rev. A 57, 4 (1998). http://pra.aps.org. Copyright © 1998 American Physical Society. Permission to use.

Abstract

We develop a method for calculation of dissociative electron attachment cross sections based on the Fano- Feshbach projection-operator approach. The coupling between the diabatic state and electron continuum is calculated with the inclusion of orthogonality scattering and long-range electron-molecule interaction. The dynamics of nuclear motion in the non-local complex potential is treated by semiclassical theory. We apply the theory to the calculation of dissociative attachment to the H₂ and HF molecules. Our results for attachment to ground-state hydrogen molecules and the near-threshold vibrational enhancement of H₂ are essentially the same as previous non-local results. However, the shape of the energy dependence of the cross section for attachment to vibrationally excited states of H₂ is slightly different. The calculated value for the total attachment cross section to the ground state of HF is consistent with the little experimental data available; more definite conclusions are difficult because of the approximate nature of the experimental results. The results for the vibrational enhancement are in very good agreement with experiment.