Incorporation of electronically nonadiabatic effects into bimolecular reactive systems. II. The collinear (H 2 + H +, H 2+ + H) system

Abstract

An exact quantum mechanical study of the collinear reactive (H 2 + H +, H 2 + + H) system with the emphasis on electronic nonadiabatic processes is presented. This system was studied both ignoring nonadiabatic effects (i.e. a single surface calculation) and incorporating them. It was found that two features, i.e. the fact that the three interacting particles have identical masses and the existence of a deep potential well in the interaction region (in the lower surface) make this system very different from any other, including its isotopic analogs. Electronic transition probabilities were calculated as a function of energy and initial vibrational state. It was established that the charge transfer process takes place due to favorable resonance conditions between high vibrational states in the lower surface and corresponding states in the upper surface. If the initia state is above the threshold for charge transfer, the process is direct (and therefore adiabatic as far as the total internal energy is concerned), and if it is below then the process takes place in the vicinity, of the interaction region where high vibrational states of the lower surface are populated due to the deep potential well in the interaction region. Applying the information theoretical approach a surprisal analysis of the results was performed. It was found that most of the results for both the one-and the two-surface cases fit the predicted behavior due to this approach very ni