Dynamics of combined electron- and proton transfer at metal electrodes

A model for combined electrochemical electron- and proton transfer is proposed, which is based on a second-quantized model Hamiltonian. It allows the calculation of potential energy surfaces for the reactions, which typically show four minima corresponding to the four system states. For the case of adiabatic transitions, reaction rates are obtained from stochastic dynamics simulations. Non-adiabatic proton transfer is examined in greater detail, and the path of the transferring proton is followed explicitly. In addition, the dependence of the reaction rate on the solvent friction and on the characteristics of the proton potential is investigated. (c) 2007 Elsevier B.V. All rights reserved.