Comment on "Communication: Simple and accurate uniform electron gas correlation energy for the full range of densities" [J. Chem. Phys. 145, 021101 (2016)]

TL;DR

This paper critiques a recent uniform electron gas correlation energy expression, proposing a parameter adjustment to better match quantum Monte Carlo data at large r_s without losing accuracy at smaller densities.

Contribution

It introduces a modified parameter in the correlation energy functional to improve agreement with QMC data at large r_s values.

Findings

Enhanced agreement with QMC data at large r_s

Maintains accuracy at small and intermediate r_s

Provides a simple adjustment to existing functional

Abstract

A simple expression for the uniform electron gas (UEG) correlation energy, recently presented in Ref. [J. Chem. Phys. 145, 021101 (2016)], deviates from the reference quantum Monte-Carlo (QMC) data at large r_s. We propose to define one of the parameters from a requirement to match the large-rs QMC data. Functional with the new parameter provides much better agreement with the QMC data at large r_s without deterioration of the functional quality at small and intermediate r_s.