Effect of viscosity on the bimolecular termination rate constants for semiquinone radicals in solution: a kinetic E.S.R. study

Abstract

The Arrhenius activation energies (E_A) have been determined for the near diffusion-controlled bimolecular termination reactions of some semiquinone radicals in a series of solvents. It was often found that E_A was less than the activation energy of diffusion (E_D) is the solvent. An explanation has been proposed in terms of the rate of encounters between the radicals and the rate at which the radicals react during an encounter.