Analytic structure factors and pair-correlation functions for the unpolarized homogeneous electron gas

TL;DR

This paper introduces a simple, accurate analytic model for the static structure factors and pair-correlation functions of the 3D unpolarized homogeneous electron gas, fitting quantum Monte Carlo data while satisfying known physical constraints.

Contribution

It presents a novel analytic model that improves upon previous models by fulfilling more physical properties and accurately interpolating recent quantum Monte Carlo data.

Findings

Model fulfills more known integral and differential properties.

Accurately interpolates extensive quantum Monte Carlo data.

Analytic in both real and reciprocal space.

Abstract

We propose a simple and accurate model for the electron static structure factors (and corresponding pair-correlation functions) of the 3D unpolarized homogeneous electron gas. Our spin-resolved pair-correlation function is built up with a combination of analytic constraints and fitting procedures to quantum Monte Carlo data, and, in comparison to previous attempts (i) fulfills more known integral and differential properties of the exact pair-correlation function, (ii) is analytic both in real and in reciprocal space, and (iii) accurately interpolates the newest, extensive diffusion-Monte Carlo data of Ortiz, Harris and Ballone [Phys. Rev. Lett. 82, 5317 (1999)]. This can be of interest for the study of electron correlations of real materials and for the construction of new exchange and correlation energy density functionals.