Stochastic Constrained Extended System Dynamics for Solving Charge Equilibration Models

TL;DR

This paper introduces a stochastic extended Lagrangian method for charge equilibration that bypasses traditional SCF calculations, enabling efficient and scalable molecular simulations with accurate property reproduction.

Contribution

It proposes a novel stochastic constrained extended Lagrangian approach that eliminates the need for SCF calculations in charge equilibration, improving computational efficiency and scalability.

Findings

Accurately reproduces structural, thermodynamic, and dynamic properties.

Demonstrates excellent weak and strong scaling in LAMMPS.

Eliminates the computational bottleneck of SCF in many-body charge solutions.

Abstract

We present a new stochastic extended Lagrangian solution to charge equilibration that eliminates self-consistent field (SCF) calculations, eliminating the computational bottleneck in solving the many-body solution with standard SCF solvers. By formulating both charges and chemical potential as latent variables, and introducing a holonomic constraint that satisfies charge conservation, the SC-XLMD method accurately reproduces structural, thermodynamic, and dynamics properties using ReaxFF, and shows excellent weak- and strong-scaling performance in the LAMMPS molecular simulation package.