Singlet exciton annihilation in anthracene crystals

Abstract

Abstract The fluorescence quenching under high excitation intensities has been studied in anthracene crystals. The singlet–singlet annihilation constant of (1 ± 0.5) × 10 −8 cm 3 s −1 is calculated from the quenching of fluorescence induced by a nitrogen 16 ns pulse laser (λ = 3371 Å). The main process of quenching under longer illumination (2 × 10 −5 s) is the interection between singlet and triplet excitons with a rate constant of (7 ± 4) × 10 −9 cm 3 s −1 .