Simple dynamic exchange-correlation kernel of the uniform electron gas

TL;DR

This paper introduces a simple, frequency-dependent exchange-correlation kernel for the uniform electron gas that accurately models electron interactions by satisfying key physical sum rules and asymptotic behaviors.

Contribution

It presents a novel, analytically simple dynamic exchange-correlation kernel that improves the modeling of the uniform electron gas by incorporating physical constraints.

Findings

Accurately reproduces wave-vector analysis of correlation energy

Matches imaginary-frequency analysis results

Satisfies sum rules and asymptotic behaviors

Abstract

We propose a simple dynamic exchange-correlation kernel of the uniform electron gas. We model the reduction of the electron-electron interaction due to short-range exchange-correlation effects by introducing a frequency-dependent error-function effective interaction. By imposing the fulfillment of the compresibility and the third-frequency-moment sum rules, as well as the correct asymptotic behavior at large wave vectors, we find an accurate and simple dynamic exchange-correlation kernel that accurately reproduces the wave-vector analysis and the imaginary-frequency analysis of the correlation energy of the uniform electron gas.