Communication: Simple and accurate uniform electron gas correlation energy for the full range of densities

Teepanis Chachiyo

doi:10.1063/1.4958669

Communication: Simple and accurate uniform electron gas correlation energy for the full range of densities

J Chem Phys. 2016 Jul 14;145(2):021101. doi: 10.1063/1.4958669.

Author

Teepanis Chachiyo¹

Affiliation

¹ The Institute for Fundamental Study "The Tah Poe Academia Institute," Naresuan University, Phitsanulok 65000, Thailand.

PMID: 27421388
DOI: 10.1063/1.4958669

Abstract

A simple correlation energy functional for the uniform electron gas is derived based on the second-order Moller-Plesset perturbation theory. It can reproduce the known correlation functional in the high-density limit, while in the mid-density range maintaining a good agreement with the near-exact correlation energy of the uniform electron gas to within 2 × 10(-3) hartree. The correlation energy is a function of a density parameter rs and is of the form a*ln(1+brs+brs (2)). The constants "a" and "b" are derived from the known correlation functional in the high-density limit. Comparisons to the Ceperley-Alder's near-exact Quantum Monte Carlo results and the Vosko-Wilk-Nusair correlation functional are also reported.