Gradient corrections to the exchangecorrelation free energy
Abstract
We develop the firstorder gradient correction to the exchangecorrelation free energy of the homogeneous electron gas for use in finitetemperature density functional calculations. Based on this, we propose and implement a simple temperaturedependent extension for functionals beyond the local density approximation. These finitetemperature functionals show improvement over zerotemperature functionals, as compared to pathintegral Monte Carlo calculations for deuterium equations of state, and perform without computational cost increase compared to zerotemperature functionals and so should be used for finitetemperature calculations. Furthermore, while the present functionals are valid at all temperatures including zero, nonnegligible difference with zerotemperature functionals begins at temperatures above 10 000 K.
 Authors:
 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
 Alternate Identifier(s):
 OSTI ID: 1180836
 Report Number(s):
 LAUR1426354
Journal ID: ISSN 10980121; PRBMDO
 Grant/Contract Number:
 AC5206NA25396
 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 10980121
 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; exchangecorrelation; warm dense matter
Citation Formats
Sjostrom, Travis, and Daligault, Jerome. Gradient corrections to the exchangecorrelation free energy. United States: N. p., 2014.
Web. doi:10.1103/PhysRevB.90.155109.
Sjostrom, Travis, & Daligault, Jerome. Gradient corrections to the exchangecorrelation free energy. United States. doi:10.1103/PhysRevB.90.155109.
Sjostrom, Travis, and Daligault, Jerome. Tue .
"Gradient corrections to the exchangecorrelation 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 exchangecorrelation free energy},
author = {Sjostrom, Travis and Daligault, Jerome},
abstractNote = {We develop the firstorder gradient correction to the exchangecorrelation free energy of the homogeneous electron gas for use in finitetemperature density functional calculations. Based on this, we propose and implement a simple temperaturedependent extension for functionals beyond the local density approximation. These finitetemperature functionals show improvement over zerotemperature functionals, as compared to pathintegral Monte Carlo calculations for deuterium equations of state, and perform without computational cost increase compared to zerotemperature functionals and so should be used for finitetemperature calculations. Furthermore, while the present functionals are valid at all temperatures including zero, nonnegligible difference with zerotemperature 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 = {Tue Oct 07 00:00:00 EDT 2014},
month = {Tue Oct 07 00:00:00 EDT 2014}
}
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