Exact thermal density functional theory for a model system: Correlation components and accuracy of the zerotemperature exchangecorrelation approximation
Abstract
Thermal density functional theory calculations often use the MerminKohnSham scheme, but employ groundstate approximations to the exchangecorrelation (XC) free energy. In the simplest solvable nontrivial model, an asymmetric Hubbard dimer, we calculate the exact manybody energies and the exact MerminKohnSham functionals for this system and extract the exact XC free energy. For moderate temperatures and weak correlation, we find this approximation to be excellent. Here we extract various exact freeenergy correlation components and the exact adiabatic connection formula.
 Authors:
 Univ. of California, Irvine, CA (United States). Dept. of Physics and Astronomy
 Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Univ. of California, Berkeley, CA (United States). Dept. of Chemistry
 Univ. of California, Irvine, CA (United States). Dept. of Physics and Astronomy; Univ. of California, Irvine, CA (United States). Dept. of Chemistry
 Publication Date:
 Research Org.:
 Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
 Sponsoring Org.:
 USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC22)
 OSTI Identifier:
 1389961
 Report Number(s):
 LLNLJRNL693045
Journal ID: ISSN 24699950; PRBMDO
 Grant/Contract Number:
 AC5207NA27344; FG0297ER25308; DGE1321846; FG0208ER46496
 Resource Type:
 Journal Article: Accepted Manuscript
 Journal Name:
 Physical Review B
 Additional Journal Information:
 Journal Volume: 93; Journal Issue: 24; Journal ID: ISSN 24699950
 Publisher:
 American Physical Society (APS)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY
Citation Formats
Smith, J. C., PribramJones, A., and Burke, K. Exact thermal density functional theory for a model system: Correlation components and accuracy of the zerotemperature exchangecorrelation approximation. United States: N. p., 2016.
Web. doi:10.1103/PhysRevB.93.245131.
Smith, J. C., PribramJones, A., & Burke, K. Exact thermal density functional theory for a model system: Correlation components and accuracy of the zerotemperature exchangecorrelation approximation. United States. doi:10.1103/PhysRevB.93.245131.
Smith, J. C., PribramJones, A., and Burke, K. 2016.
"Exact thermal density functional theory for a model system: Correlation components and accuracy of the zerotemperature exchangecorrelation approximation". United States.
doi:10.1103/PhysRevB.93.245131. https://www.osti.gov/servlets/purl/1389961.
@article{osti_1389961,
title = {Exact thermal density functional theory for a model system: Correlation components and accuracy of the zerotemperature exchangecorrelation approximation},
author = {Smith, J. C. and PribramJones, A. and Burke, K.},
abstractNote = {Thermal density functional theory calculations often use the MerminKohnSham scheme, but employ groundstate approximations to the exchangecorrelation (XC) free energy. In the simplest solvable nontrivial model, an asymmetric Hubbard dimer, we calculate the exact manybody energies and the exact MerminKohnSham functionals for this system and extract the exact XC free energy. For moderate temperatures and weak correlation, we find this approximation to be excellent. Here we extract various exact freeenergy correlation components and the exact adiabatic connection formula.},
doi = {10.1103/PhysRevB.93.245131},
journal = {Physical Review B},
number = 24,
volume = 93,
place = {United States},
year = 2016,
month = 6
}
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