Modeling Electron Transfer in Diffusive Multidimensional Electrochemical Systems

We analyze different stochastic approaches for simulating electron transfer and potential sweep experiments in diffusive multidimensional electrochemical systems. In particular, we focus on a simple two-dimensional system, where one dimension is a traditional mass diffusion coordinate moving reactants from bulk solution to an electrode, and a second dimension represents a reorganization coordinate capturing solvent motion. We find that this multidimensional system can indeed be reduced to a simpler one-dimensional model, provided certain circumstances pertaining to separability between the two coordinates are met. Our results should begin to bridge the gap between continuum models of electrochemical dynamics/transport and ab initio models of surface electronic structure.