Effects of Slow Vibrational Relaxation on Anomalous Stokes'-Shifted Luminescence and Energy Transfer in Solids

摘要

An analysis is presented of the emission spectrum to be expected from model centers in vibrationally excited and electronically excited states. It is shown that for centers which normally exhibit a sizable Stokes' shift there will be, for a short time following excitation, a large component of emission at approximately twice the usual Stokes' shift. This anomalous emission would be detectable by ultra-fast (pico-second) excitation and detection, and in selected systems by conventional means. Its measurement would provide an estimate of the vibrational relaxation time of the center. The implications of the relaxation rate on electronic energy transfer between like species are briefly discussed. (Author)