Exchange Monte Carlo for Molecular Simulations with Monoelectronic Hamiltonians

TL;DR

This paper presents a Monte Carlo method for atomistic simulations of systems with monoelectronic Hamiltonians, accurately capturing electronic and nuclear thermalization and analyzing electronic temperature effects on thermodynamics.

Contribution

It introduces a kinetic Monte Carlo scheme for exact electronic occupation sampling in atomistic simulations, bridging electronic and nuclear thermalization.

Findings

Electronic occupation numbers match Fermi-Dirac statistics.

Electronic temperature influences thermodynamic properties of liquids and clusters.

Method enables more accurate simulations of electronic effects in materials.

Abstract

We introduce a general Monte Carlo scheme for achieving atomistic simulations with monoelectronic Hamiltonians including the thermalization of both nuclear and electronic degrees of freedom. The kinetic Monte Carlo algorithm is used to obtain the exact occupation numbers of the electronic levels at canonical equilibrium, and comparison is made with Fermi-Dirac statistics in infinite and finite systems. The effects of a nonzero electronic temperature on the thermodynamic properties of liquid silver and sodium clusters are presented.