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Title: Gradient corrections to the exchange-correlation free energy

Abstract

We develop the first-order gradient correction to the exchange-correlation free energy of the homogeneous electron gas for use in finite-temperature density functional calculations. Based on this, we propose and implement a simple temperature-dependent extension for functionals beyond the local density approximation. These finite-temperature functionals show improvement over zero-temperature functionals, as compared to path-integral Monte Carlo calculations for deuterium equations of state, and perform without computational cost increase compared to zero-temperature functionals and so should be used for finite-temperature calculations. Furthermore, while the present functionals are valid at all temperatures including zero, non-negligible difference with zero-temperature functionals begins at temperatures above 10 000 K.

Authors:
 [1];  [1]
  1. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Publication Date:
Research Org.:
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1246924
Report Number(s):
LA-UR-14-26354
Journal ID: ISSN 1098-0121; PRBMDO
Grant/Contract Number:
AC52-06NA25396
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Physical Review. B, Condensed Matter and Materials Physics
Additional Journal Information:
Journal Volume: 90; Journal Issue: 15; Journal ID: ISSN 1098-0121
Publisher:
American Physical Society (APS)
Country of Publication:
United States
Language:
English
Subject:
74 ATOMIC AND MOLECULAR PHYSICS; 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; 36 MATERIALS SCIENCE; 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; density functional theory; exchange-correlation; warm dense matter

Citation Formats

Sjostrom, Travis, and Daligault, Jerome. Gradient corrections to the exchange-correlation free energy. United States: N. p., 2014. Web. doi:10.1103/PhysRevB.90.155109.
Sjostrom, Travis, & Daligault, Jerome. Gradient corrections to the exchange-correlation free energy. United States. doi:10.1103/PhysRevB.90.155109.
Sjostrom, Travis, and Daligault, Jerome. 2014. "Gradient corrections to the exchange-correlation free energy". United States. doi:10.1103/PhysRevB.90.155109. https://www.osti.gov/servlets/purl/1246924.
@article{osti_1246924,
title = {Gradient corrections to the exchange-correlation free energy},
author = {Sjostrom, Travis and Daligault, Jerome},
abstractNote = {We develop the first-order gradient correction to the exchange-correlation free energy of the homogeneous electron gas for use in finite-temperature density functional calculations. Based on this, we propose and implement a simple temperature-dependent extension for functionals beyond the local density approximation. These finite-temperature functionals show improvement over zero-temperature functionals, as compared to path-integral Monte Carlo calculations for deuterium equations of state, and perform without computational cost increase compared to zero-temperature functionals and so should be used for finite-temperature calculations. Furthermore, while the present functionals are valid at all temperatures including zero, non-negligible difference with zero-temperature functionals begins at temperatures above 10 000 K.},
doi = {10.1103/PhysRevB.90.155109},
journal = {Physical Review. B, Condensed Matter and Materials Physics},
number = 15,
volume = 90,
place = {United States},
year = 2014,
month =
}

Journal Article:
Free Publicly Available Full Text
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