APPLICATION OF CLUSTER DISTRIBUTIONS TO ENERGY-TRANSFER IN NAPHTHALENE CHOLEIC ACID CRYSTALS

The cluster distributions for different concentrations of C10H8 and C1 0D8 in naphthalene choleic acid were determined by a computer simulati on in order to model the energy-transfer dynamics. The results of the simulation agree with experiment, indicating that the change in the en ergy transfer efficiency with increasing C10H8 concentration is caused by tbe growth of C10Hs clusters and then limited by the small number of sites visited during the lifetime of the excitation. A random walk simulation was used to determine the triplet exciton density and exten t of exciton-exciton annihilation under various conditions. The rate c onstant for triplet exciton annihilation was estimated to be 1.5 x 10( -18) cm3 s-1 compared to 0.5 cm3 s-1 in naphthalene crystals.