Nonradiative heterofission of a singlet host exciton into a pair of triplet electronic excitations in doped aromatic hydrocarbon molecular crystals

The nonradiative heterofission process of a singlet host exciton into one triplet host exciton and one triplet guest molecule electronic excitation in some aromatic hydrocarbon molecular crystals is investigated theoretically. The formulae for the heterofission rate constants are derived and discussed and used for the numerical estimates. The conditions for the occurence of the heterofission of a singlet host exciton in the investigated crystals are discussed.