Quantum Monte Carlo modelling of the spherically averaged structure factor of a many-electron system

TL;DR

This paper introduces a quantum Monte Carlo method to accurately model the spherically averaged structure factor of many-electron systems, significantly reducing Coulomb finite-size errors in ground-state energy calculations.

Contribution

The paper presents a novel Monte Carlo approach for modeling the structure factor that effectively minimizes finite-size errors in electronic structure computations.

Findings

Successfully applied to homogeneous electron gas

Reduces Coulomb finite-size errors in energy calculations

Applicable to inhomogeneous systems

Abstract

The interaction and exchange-correlation contributions to the ground-state energy of an arbitrary many-electron system can be obtained from a spherical average of the wavevector-dependent diagonal structure factor (SF). We model the continuous-k spherically averaged SF using quantum Monte Carlo calculations in finite simulation cells. We thus derive a method that allows to substantially reduce the troublesome Coulomb finite-size errors that are usually present in ground-state energy calculations. To demonstrate this, we perform variational Monte Carlo calculations of the interaction energy of the homogeneous electron gas. The method is, however, equally applicable to arbitrary inhomogeneous systems.