Theory of the Vibronic Transitions of Substitutional Impurities in Molecular Crystals

摘要

A theory for the vibronic states of a single guest molecule in the vicinity of bands of single exciton states of the host crystal is presented. It is assumed that the lattice is rigid, and that the wavefunctions of isolated molecules are Bornndash;Oppenheimer separable. Expressions are given for the excitation energies, transition probabilities, and polarization ratios of a general guest which are much simpler and easier to interpret than any given before. It is shown that the guest transitions exhibit anomalous polarization ratios (Rashba effect) near the host bands. The use of guests to locate exciton band edges and find guestndash;host interactions is discussed.