The biexcitonic quenching and exciton migration rate in aromatic crystals

Abstract
Fluorescence quenching due to exciton-exciton interaction was studied for the crystals of fluoranthene and 1,2,4,5-tetracyanobenzene-durene complex with the use of a nitrogen gas laser and the rate constant for the biexcitonic quenching process γ and the rate of the exciton migration λ were obtained for both crystals. The γ value for both crystals was found to increase with increasing temperature. Finally, we obtained the phonon frequency which contributes to the transport of excitons through exciton-phonon coupling.