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arXiv · 1804.04938

Correlation energies of the high-density spin-polarized electron gas to meV accuracy

Michele Ruggeri·Pablo López Ríos·Ali Alavi
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Abstract

We present a novel combination of quantum Monte Carlo methods and a finite size extrapolation framework with which we calculate the thermodynamic limit of the exact correlation energy of the polarized electron gas at high densities to meV accuracy, $-40.44(5)$ and $-31.70(4)$ mHa at $r_{\rm s}=0.5$ and $1$, respectively. The fixed-node error is characterized and found to exceed $1$ mHa, and we show that the magnitude of the correlation energy of the polarized electron gas is underestimated by up to $6$ meV by the Perdew-Wang parametrization, for which we suggest improvements.

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Michele Ruggeri, Pablo López Ríos, Ali Alavi. 2018-04-13. Correlation energies of the high-density spin-polarized electron gas to meV accuracy. https://doi.org/10.1103/physrevb.98.161105

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