Abstract :
Effects of nonequilibrated phonon modes on the rates of nonadiabatic reactions are analysed. A model is studied consisting of a thermal bath and a single nonequilibrated phonon mode, characterized by the microcanonical energy distribution. Generalization of the Kac formula for the frequency of zeros of a stochastic function is employed for the derivation of the expression for the averaged density of the reactive flux. The problem of evaluation of the nonadiabatic rate is reduced to quadratures. Numerical analysis of the problem for the particular case of an Ohmic thermal bath is presented. The effects of varying the energy of the nonequilibrated mode and the projection of the reactive coordinate on this mode are explored. Results are compared to the model in which a selected phonon mode is characterized by the equilibrium energy distribution, but with the temperature different from that of the thermal bath.
