Non-exponential time behavior of electron transfer in an inhomogeneous polar medium

Abstract

An analysis is made of electron transfer (ET) in a polar medium described by a distribution of dielectric relaxation times, for the case that intramolecular contributions to the ET are negligible. The generalized moment expansion is used for an approximate multi-exponential description of the non-exponential time behavior of the ET. As an example, ET in glycerol-like solvents is considered, treated by the spatially inhomogeneous model for dielectric relaxation. For this model the ET rate at long times is found to vary as τ0−1, τ0 being a dielectric relaxation time parameter, in contrast with a fractional dependence at short times.