Rate constant of bimolecular triplet energy transfer from chrysene in the higher triplet excited states

The rate constant of the bimolecular triplet energy transfer from chrysene in the second higher triplet excited state (T-2) to triplet quenchers (Q) such as biphenyl, naphthalene, and carbon tetrachloride was determined based on the lifetime of chrysene(T-2) (45 +/- 7 ps) measured directly with ns-ps two-color two-laser flash photolysis method. The rate constant was found to be larger than the diffusion-controlled rate constant in the solvents. The occurrence of the fast bimolecular triplet energy transfer is considered clear evidence of the Ware theoretical model on the energy transfer quenching of the excited species with short lifetimes by the quencher.