Solvent Donicity and Dielectric Continuum Effects in Amalgam Formation Reactions. A Study of the Reduction of Cu(I) in the Nitrile Solvents

Kinetic parameters are reported for the electroreduction of CuI from four nitrile solvents as a function of both electrode potential and temperature under circumstances where the solvent is the ligand surrounding the ion being reduced. This reaction is shown to be atypical in that the apparent transfer coefficient is close to unity. It is argued that the rate controlling step takes place in the inner layer very close to the electrodesolution interface so that the effect of the electrodes field is very important. The role of the solvent in determining the characteristics of the transition state is discussed both with respect to its function in the immediate environment of the reactant, and its role in the macroscopic electrostatic effects.