# Generalized Moment Correction for Long-Ranged Electrostatics

## TL;DR

This paper introduces a rigorous, parameter-free method for accurately approximating long-range electrostatics in molecular simulations by canceling multipole moments, offering an efficient alternative to traditional Ewald summation.

## Contribution

A new formally exact method that cancels infinitely many multipole moments without damping parameters, improving long-range electrostatics modeling in molecular dynamics.

## Key findings

- Method accurately reproduces radial distribution functions.
- Achieves comparable accuracy to Ewald summation.
- Applicable to dipole-dipole interactions.

## Abstract

Describing long-ranged electrostatics using short-ranged pair potentials is appealing since the computational complexity scales linearly with the number of particles. The foundation of this approach is to mimic the long-ranged medium response by cancelling electric multipoles within a small cutoff sphere. We propose a rigorous and formally exact new method that cancels up to infinitely many multipole moments and is free of operational damping parameters often required in existing theories. Using molecular dynamics simulations of water with and without added salt, we discuss radial distribution functions, Kirkwood-Buff integrals, dielectrics, diffusion coefficients, and angular correlations in relation to existing electrostatic models. We find that the proposed method is an efficient and accurate alternative for handling long-ranged electrostatics as compared to Ewald summation schemes. The methodology and proposed parameterization is applicable also for dipole-dipole interactions.