Absorption and fluorescence by thin molecular crystals, I. Theory

Abstract

A theory of exciton-photon states of molecular crystals is given to include the effect of finite crystal size. The internal and external retarded fields are calculated by summation of contributions by individual molecules and are shown compatible with the Ewald-Oseen theorem. Absorption processes (involving crystal states in an external driving field) and fluorescence (quasi-stationary states) are separately treated, and compared.