Computing Solvation Shell Dynamics and Energetics in Electron Transfer Reactions via Molecular Dynamics Simulations

TL;DR

This paper introduces a computationally efficient method using molecular dynamics to analyze solvation shell dynamics and energetics in electron transfer reactions, enhancing understanding of transition states and water network evolution.

Contribution

It presents a novel generalized reaction coordinate based on nuclear charge, enabling targeted quantification of solvation shell changes during electron transfer.

Findings

Efficient computation of free energy profiles for electron transfer

Identification of transition state geometries

Analysis of water network evolution during reactions

Abstract

Marcus theory is fundamental to describing electron transfer reactions and quantifying their rates, effectively representing the energy surface associated with an electron transfer from the reactant to the product ionic state via parabolas within a reaction coordinate diagram. Here, we present an intuitive and computationally efficient generalised reaction coordinate amenable to molecular dynamics simulations. By utilising the nuclear charge of the ion, we are able to quantify in a targeted approach changes in the ion's solvation shell, thereby efficiently obtaining the free energy profile associated with the electron transfer, the transition state geometry and the evolution of the water network.