Manipulating reactant–product distributions in electron transfer reactions with a laser field

The effect of a strong cw laser field on the process of nonadiabatic electron transfer in polar solvents is considered. First-order kinetic equations are derived in which the forward and backward rate constants depend on the electric field parameters. The forward rate constant, which governs the early time dynamics, exhibits dramatic variation with field intensity in the barrierless and activationless regimes. The sum of forward and backward rate constants, which determines the long time kinetics and hence may be termed the full rate constant, is less sensitive to the field intensity in the same regime of molecular parameter space. It is shown that the asymptotic populations of the reactant and product states are in general non-Boltzmann; their ratio can be varied by many orders of magnitude as the frequency and intensity of the applied electric field are varied.