Short-range correlation energy of the relativistic homogeneous electron gas

TL;DR

This paper develops a relativistic short-range correlation functional for density-functional theory, based on RPA calculations of the relativistic homogeneous electron gas, aiming to improve electronic structure modeling of heavy-element systems.

Contribution

It introduces a new relativistic short-range correlation functional derived from RPA calculations, suitable for use in relativistic density-functional theory with heavy elements.

Findings

Functional accurately models high-density correlation energy

Fits well to parametrized expressions from RPA data

Potentially improves electronic structure calculations for heavy elements

Abstract

We construct the complementary short-range correlation relativistic local-density-approximation functional to be used in relativistic range-separated density-functional theory based on a Dirac-Coulomb Hamiltonian in the no-pair approximation. For this, we perform relativistic random-phase-approximation calculations of the correlation energy of the relativistic homogeneous electron gas with a modified electron-electron interaction, we study the high-density behavior, and fit the results to a parametrized expression. The obtained functional should eventually be useful for electronic-structure calculations of strongly correlated systems containing heavy elements.