Construction of exchangecorrelation functionals through interpolation between the noninteracting and the strongcorrelation limit
Abstract
Drawing on the adiabatic connection of density functional theory, exchangecorrelation functionals of KohnSham density functional theory are constructed which interpolate between the extreme limits of the electronelectron interaction strength. The first limit is the noninteracting one, where there is only exchange. The second limit is the strong correlated one, characterized as the minimum of the electronelectron repulsion energy. The exchangecorrelation energy in the strongcorrelation limit is approximated through a model for the exchangecorrelation hole that is referred to as nonlocalradius model [L. O. Wagner and P. GoriGiorgi, Phys. Rev. A 90, 052512 (2014)]. Using the noninteracting and strongcorrelated extremes, various interpolation schemes are presented that yield new approximations to the adiabatic connection and thus to the exchangecorrelation energy. Some of them rely on empiricism while others do not. Several of the proposed approximations yield the exact exchangecorrelation energy for oneelectron systems where local and semilocal approximations often fail badly. Other proposed approximations generalize existing global hybrids by using a fraction of the exchangecorrelation energy in the strongcorrelation limit to replace an equal fraction of the semilocal approximation to the exchangecorrelation energy in the strongcorrelation limit. The performance of the proposed approximations is evaluated for molecular atomization energies, total atomic energies,more »
 Authors:
 Département de Chimie, Université de Montréal, C.P. 6128, Succursale A, Montréal, Québec H3C 3J7 (Canada)
 Department of Chemistry, Technische Universität Berlin, Strasse des 17 Juni, Berlin (Germany)
 Publication Date:
 OSTI Identifier:
 22489627
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Journal of Chemical Physics; Journal Volume: 143; Journal Issue: 12; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; 97 MATHEMATICAL METHODS AND COMPUTING; APPROXIMATIONS; ATOMIZATION; DENSITY FUNCTIONAL METHOD; ELECTRON CORRELATION; ELECTRONELECTRON COLLISIONS; ELECTRONELECTRON INTERACTIONS; ELECTRONS; HYBRIDIZATION; INTERPOLATION; NUCLEAR ENERGY
Citation Formats
Zhou, Yongxi, Ernzerhof, Matthias, Email: Matthias.Ernzerhof@UMontreal.ca, and Bahmann, Hilke. Construction of exchangecorrelation functionals through interpolation between the noninteracting and the strongcorrelation limit. United States: N. p., 2015.
Web. doi:10.1063/1.4931160.
Zhou, Yongxi, Ernzerhof, Matthias, Email: Matthias.Ernzerhof@UMontreal.ca, & Bahmann, Hilke. Construction of exchangecorrelation functionals through interpolation between the noninteracting and the strongcorrelation limit. United States. doi:10.1063/1.4931160.
Zhou, Yongxi, Ernzerhof, Matthias, Email: Matthias.Ernzerhof@UMontreal.ca, and Bahmann, Hilke. 2015.
"Construction of exchangecorrelation functionals through interpolation between the noninteracting and the strongcorrelation limit". United States.
doi:10.1063/1.4931160.
@article{osti_22489627,
title = {Construction of exchangecorrelation functionals through interpolation between the noninteracting and the strongcorrelation limit},
author = {Zhou, Yongxi and Ernzerhof, Matthias, Email: Matthias.Ernzerhof@UMontreal.ca and Bahmann, Hilke},
abstractNote = {Drawing on the adiabatic connection of density functional theory, exchangecorrelation functionals of KohnSham density functional theory are constructed which interpolate between the extreme limits of the electronelectron interaction strength. The first limit is the noninteracting one, where there is only exchange. The second limit is the strong correlated one, characterized as the minimum of the electronelectron repulsion energy. The exchangecorrelation energy in the strongcorrelation limit is approximated through a model for the exchangecorrelation hole that is referred to as nonlocalradius model [L. O. Wagner and P. GoriGiorgi, Phys. Rev. A 90, 052512 (2014)]. Using the noninteracting and strongcorrelated extremes, various interpolation schemes are presented that yield new approximations to the adiabatic connection and thus to the exchangecorrelation energy. Some of them rely on empiricism while others do not. Several of the proposed approximations yield the exact exchangecorrelation energy for oneelectron systems where local and semilocal approximations often fail badly. Other proposed approximations generalize existing global hybrids by using a fraction of the exchangecorrelation energy in the strongcorrelation limit to replace an equal fraction of the semilocal approximation to the exchangecorrelation energy in the strongcorrelation limit. The performance of the proposed approximations is evaluated for molecular atomization energies, total atomic energies, and ionization potentials.},
doi = {10.1063/1.4931160},
journal = {Journal of Chemical Physics},
number = 12,
volume = 143,
place = {United States},
year = 2015,
month = 9
}

The correlation factor model is developed in which the spherically averaged exchangecorrelation hole of KohnSham theory is factorized into an exchange hole model and a correlation factor. The exchange hole model reproduces the exact exchange energy per particle. The correlation factor is constructed in such a manner that the exchangecorrelation energy correctly reduces to exact exchange in the high density and rapidly varying limits. Four different correlation factor models are presented which satisfy varying sets of physical constraints. Three models are free from empirical adjustments to experimental data, while one correlation factor model draws on one empirical parameter. The correlationmore »

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