The first peak (0-0 transition) of the singlet-triplet delayed fluorescence excitation spectrum in pyrene has been investigated in polarized light. The b-polarized transition is found to be at higher energy than the a-polarized transition by a Davydov splitting of 2.4 ± 0.6 cm-1. An expression for the energy bands ε(k→) is derived and related to the Davydov splitting. Transport properties of the triplet excitons have been evaluated and indicate that the diffusion of triplet excitons in pyrene is due more to a hopping process than to coherent band motion.
ASJC Scopus subject areas
- Condensed Matter Physics