Open Quantum System Approach to the Modeling of Spin Recombination Reactions

TL;DR

This paper develops a unified quantum mechanical framework for modeling spin-dependent radical pair reactions, linking microscopic interactions to the master equations used in chemical kinetics.

Contribution

It introduces a systematic approach to derive reaction operators from microscopic models, unifying various existing mechanisms in spin chemistry.

Findings

Provides a microscopic derivation of reaction operators

Unifies different models of spin-selective recombination

Enhances understanding of underlying quantum processes

Abstract

In theories of spin-dependent radical pair reactions, the time evolution of the radical pair, including the effect of the chemical kinetics, is described by a master equation in the Liouville formalism. For the description of the chemical kinetics, a number of possible reaction operators have been formulated in the literature. In this work, we present a framework that allows for a unified description of the various proposed mechanisms and the forms of reaction operators for the spin-selective recombination processes. Based on the concept that master equations can be derived from a microscopic description of the spin system interacting with external degrees of freedom, it is possible to gain insight into the underlying microscopic processes and to develop a systematic approach towards determining the specific form of reaction operator in concrete scenarios.