Equilibrium solvation in quadrupolar solvents

TL;DR

This paper develops a microscopic theory for equilibrium solvation in quadrupolar solvents, utilizing structure factors of quadrupolar polarization, and validates it through simulations and application to electron transfer reactions.

Contribution

It introduces a new theoretical framework for solvation in quadrupolar solvents based on autocorrelation functions and applies a perturbation approach for structure factors.

Findings

Theory agrees with Monte Carlo simulation results.

Successfully applied to calculate activation barriers in electron transfer.

Provides a general method for dense quadrupolar solvents.

Abstract

We present a microscopic theory of equilibrium solvation in solvents with zero dipole moment and non-zero quadrupole moment (quadrupolar solvents). The theory is formulated in terms of autocorrelation functions of the quadrupolar polarization (structure factors). It can be therefore applied to an arbitrary dense quadrupolar solvent for which the structure factors are defined. We formulate a simple analytical perturbation treatment for the structure factors. The solute is described by coordinates, radii, and partial charges of constituent atoms. The theory is tested on Monte Carlo simulations of solvation in model quadrupolar solvents. It is also applied to the calculation of the activation barrier of electron transfer reactions in a cleft-shaped donor-acceptor complex dissolved in benzene with the structure factors of quadrupolar polarization obtained from Molecular Dynamics simulations.