Semiclassical studies of planar reactive H+H2

Abstract

The semiclassical scattering theory recently developed by Miller [J. Chem. Phys. 53, 1949 (1970)] is applied to the planar reactive scattering of H + H₂ to test the accuracy and practicality of the semiclassical technique and to investigate the differences between the quantum and classical results obtained by Saxon and Light [J. Chem. Phys. 56, 3874, 3885 (1971); 57, 2758 (1972)]. Though the semiclassical probabilities agree surprisingly well with the quantum results for some transitions, they do not support the quasiselection rule observed in the quantum calculations, and thus the semiclassical theory does not predict the forward peak characteristic of the quantum differential cross section. Several difficulties involved in applying the semiclassical prescription are discussed, which seem to severely limit the usefulness of this approach.