Effect of dimensionality and size on triplet-triplet annihilation

A statistical approach and Monte Carlo simulations in regular lattices were used to study the dynamics of triplet-triplet annihilation (TTA) in 1D, 2D and 3D nanodomains. It was shown that the phosphorescence and triplet-triplet absorption decays can generally be fitted with a sum of two exponentials. The first exponential corresponds to domains containing initially one triplet and the second exponential to domains initially with two triplets. The triplet survival probability and the dependence of the annihilation rate constant on the energy migration rate, W, annihilation rate, V, and size of the domain, M, was obtained by Monte Carlo simulations in the diffusion-influenced limit (V ≫ W).