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arXiv · 1311.4903

Local Spin-density Approximation Exchange-correlation Free-energy Functional

Valentin V. Karasiev·Travis Sjostrom·James Dufty·S. B. Trickey
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Abstract

An accurate analytical parametrization for the exchange-correlation free energy of the homogeneous electron gas, including interpolation for partial spin-polarization, is derived via thermodynamic analysis of recent restricted path integral Monte-Carlo (RPIMC) data. This parametrization constitutes the local spin density approximation (LSDA) for the exchange-correlation functional in density functional theory. The new finite-temperature LSDA reproduces the RPIMC data well, satisfies the correct high-density and low- and high-$T$ asymptotic limits, and is well-behaved beyond the range of the RPIMC data, suggestive of broad utility.

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Valentin V. Karasiev, Travis Sjostrom, James Dufty, S. B. Trickey. 2013-11-19. Local Spin-density Approximation Exchange-correlation Free-energy Functional. https://doi.org/10.1103/physrevlett.112.076403

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