Triplet exciton percolation and superexchange: Naphthalene C10H8–C10D8

Abstract
The phosphorescence of betamethylnaphthalene doped into a naphthalene−h8/naphthalene−d8 mixed crystal has been measured. The results demonstrate that (1) dynamical exciton percolation does occur (i.e., a transition from an exciton insulator to an exciton conductor), that (2) it is very useful for the investigation of energy transfer in molecular aggregates, and that (3) it is a critical test of our current knowledge of exciton exchange and superexchange. (AIP)