Electron transfer in solution : nonadiabatic dynamics and applications to catalysis

Abstract

A mechanistic understanding of electron transfer in solution will advance our understanding of many chemical processes, including heterogeneous redox catalysis and photochemistry-processes which are fundamental in energy storage and solar energy conversion, among other applications. In this thesis, we first apply density functional theory (DFT) to study the mechanistic intermediates of the oxygen evolution reaction (OER) on metal-oxide redox catalysts. From these thermodynamic calculations, we are able to gain insight into catalytic design principles. Afterwards, we study nonadiabatic electron transfer in solution. After benchmarking various resummations of a fourth-order perturbation theory expansion of a generalized master equation memory kernel for the spin-boson model, we apply our theoretical understanding to study the short-time dynamics of electron transfer beyond the Condon approximation in aqueous iron(II) / iron(III) electron self-exchange. We discuss the application of this method to identify conical intersections in condensed-phase photochemistry. Finally, we examine the range of validity of electron couplings predicted by constrained density functional theory with configuration interaction (CDFT-CI). The nonadiabatic electron transfer methods developed and applied in this work will contribute to a relatively sparse computational toolkit for studying challenging problems in photochemical electron transfer, such as the prediction of nonradiative decay rates from first principle; these, in turn, will contribute to the design of catalytic materials for solar energy conversion.