Simulation of the kinetics of phosphorescence buildup of energy donor molecules in matrix-isolated donor–acceptor pairs

A mathematical model is proposed for describing the kinetics of accumulation of donor molecules in the triplet state for matrix-isolated donor–acceptor pairs. Using this model, computer simulation of the kinetics of accumulation of triplet excitations and phosphorescence buildup of the donor is performed. It is found that for certain relations between the rate constants of transitions for the donor and acceptor of the triplet excitation energy, the kinetics of phosphorescence buildup and the quantum yield of the donor phosphorescence depend on the excitation power.