Pulse radiolysis studies of ion association

Abstract

Kinetic spectrophotometry has been used to follow the ion association process between benzo-phenone radical anions and alkali metal cations, in low dielectric media. This process was shown to be diffusion-controlled. The spectral shifts induced by the nearby metal cations indicate that the larger cations form contact ion-pairs, whereas Li⁺ and Na⁺ form solvent-separated species, in which the anion partly penetrates the cationic solvent shell.