Coulomb Interactions via Local Dynamics: A Molecular--Dynamics Algorithm

TL;DR

This paper presents a molecular dynamics algorithm for Coulomb interactions that couples charges to a local electromagnetic field, related to Car-Parrinello methods, with corrections for unphysical self-energies and demonstrated parallelization.

Contribution

It introduces a novel MD algorithm for Coulomb forces based on local electromagnetic fields, connecting it to existing Car-Parrinello approaches and addressing self-energy issues.

Findings

Method is related to Car-Parrinello approach.

Unphysical self-energies are corrected with a lattice Green's function scheme.

Preliminary benchmarks demonstrate the method's feasibility.

Abstract

We derive and describe in detail a recently proposed method for obtaining Coulomb interactions as the potential of mean force between charges which are dynamically coupled to a local electromagnetic field. We focus on the Molecular Dynamics version of the method and show that it is intimately related to the Car--Parrinello approach, while being equivalent to solving Maxwell's equations with freely adjustable speed of light. Unphysical self--energies arise as a result of the lattice interpolation of charges, and are corrected by a subtraction scheme based on the exact lattice Green's function. The method can be straightforwardly parallelized using standard domain decomposition. Some preliminary benchmark results are presented.