Kinetics of geminate recombination of aromatic free radicals

Abstract

Nanosecond laser flash photolysis techniques were used to observe the geminate recombination kinetics of 2-(4'-diphenylaminophenyl)-indandione-1,3-yl radicals (R) in vaseline oil at 0°C. The kinetics are closely described by the Kofman-Burshtein model. The rate of diffusion-controlled recombination of R by random encounters in the bulk was also measured. The kinetics of geminate recombination and recombination in the bulk are described by the same parameters (diffusion coefficient (1.8 ± O.6) × 10 −8 cm 2/s and reaction radius 13.2Å).