Kinetics of oxidation of transition-metal ions by halogen radical anions. Part II. The oxidation of cobalt(II) by dichloride ions generated by flash photolysis

Abstract

The radical anion Cl₂^–, generated by flash photolysis of solutions containing Cl₃^–, oxidizes cobalt(II) to cobalt(III). At 25 °C and I= 0·3M, the rate constant is (1·4 ± 0·2)× 10⁶ l mol^–1 s^–1(ΔH^‡= 29 ± 4 kJ mol^–1 and ΔS^‡=–31 ±10 J K^–1 mol^–1). The reaction is inner sphere–substitution controlled, the initial product being CoCl²⁺ which is not labile on the time scale of the oxidation reaction.