Dielectric response with short-ranged electrostatics

TL;DR

This paper investigates the dielectric properties of a water model with short-ranged electrostatics using local molecular field theory, showing good agreement with known behaviors and supporting LMFT for solvation studies.

Contribution

It introduces and evaluates a short-ranged electrostatic water model within LMFT, demonstrating its effectiveness in capturing dielectric properties.

Findings

Short-ranged electrostatics can accurately model dielectric behavior.

LMFT effectively accounts for long-range electrostatic effects.

The model's shortcomings are explainable and manageable.

Abstract

The dielectric nature of polar liquids underpins much of their ability to act as useful solvents, but its description is complicated by the long-ranged nature of dipolar interactions. This is particularly pronounced under the periodic boundary conditions commonly used in molecular simulations. In this article, the dielectric properties of a water model whose intermolecular electrostatic interactions are entirely short-ranged are investigated. This is done within the framework of local molecular field theory (LMFT), which provides a well controlled mean-field treatment of long-ranged electrostatics. This short-ranged model gives a remarkably good performance on a number of counts, and its apparent shortcomings are readily accounted for. These results not only lend support to LMFT as an approach for understanding solvation behavior, but are relevant to those developing interaction potentials based on local descriptions of liquid structure.