Forward and reverse excitation energy transport and concentration depolarization in two-component systems

Abstract

A theoretical study of forward and reverse electronic excitation energy transport and trapping in a two-component disordered system is presented. The method used is an extension of the diagrammatic technique applied by Loring, Andersen, and Fayer to the system with no reverse energy transfer. The results of an exact diagrammatic analysis of the configuration-averaged Green function of the master equation are presented. The following steady-state observables: relative donor quantum yield and emission anisotropy, are obtained using the self-consistent approximation. The numerical results for Förster dipole—dipole transfer are evaluated within the framework of the improved two-body approximation introduced herein (the two-body approximation and the three-body treatment of the energy migration process in the donor ensemble). A comparison with the experimental data and Monte Carlo results is presented.