Spectral analysis of electron transfer kinetics II

TL;DR

This paper applies spectral analysis to study electron transfer kinetics in Debye solvents, revealing various kinetic regimes and behaviors through a unified framework, and discusses limitations in large reorganization energy cases.

Contribution

It introduces a spectral analysis method to investigate diverse electron transfer kinetic regimes and compares these with existing theoretical models.

Findings

Identification of multiple kinetic regimes including adiabatic and nonadiabatic limits

Demonstration of dynamic bath effects on electron transfer

Observation of non-physical behavior in large reorganization energy cases

Abstract

Electron transfer processes in Debye solvents are studied using a spectral analysis method recently proposed. Spectral structure of a nonadiabatic two-state diffusion equation is investigated to reveal various kinetic regimes characterized by a broad range of physical parameters; electronic coupling, energy bias, reorganization energy, and solvent relaxation rate. Within this unified framework, several kinetic behaviors of the electron transfer kinetics, including adiabatic Rabi oscillation, crossover from the nonadiabatic to adiabatic limits, transition from the incoherent to coherent kinetic limits, and dynamic bath effect, are demonstrated and compared with results from previous theoretical models. Dynamics of the electron transfer system is also calculated with the spectral analysis method. It is pointed out that in the large reorganization energy case the nonadiabatic diffusion equation exhibits a non-physical behavior, yielding a negative eigenvalue.