Bond-breaking electron transfer of diatomic reactants at metal electrodes

A model Hamiltonian for concerted bond breaking and electron-transfer reactions at metal electrodes is presented; it combines elements of the Marcus theory, the Anderson-Newns model, and tight binding. The formalism is developed explicitly for the dissociation of a homonuclear diatomic molecule. A set of self-consistent equations for the densities of states of the reactants is derived, which allows the calculation of potential energy surfaces as a function of the molecular bond length and the generalized solvent coordinate. Model calculations have been performed both for the reduction and the oxidation of the molecule. (c) 2008 Elsevier B.V. All rights reserved.