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DOE OSTI · 2479513

Thermal mean-field theories

Gu, Pinhao [University of Illinois at Urbana-Champaign, IL (United States); University of Illinois at Urbana-Champaign] (ORCID:0009000011369485)·Hirata, So [University of Illinois at Urbana-Champaign, IL (United States)] (ORCID:0000000295781502)
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Abstract

Several closely related ab initio thermal mean-field theories for fermions, both well-established and new ones, are compared with one another at the formalism level and numerically. The theories considered are Fermi–Dirac theory; thermal Hartree–Fock (HF) theory; two modifications of the thermal single-determinant and the first-order finite-temperature many-body perturbation theory based on a zero-temperature or thermal HF reference. Furthermore, thermal full-configuration-interaction theory is used as the benchmark.

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74 ATOMIC AND MOLECULAR PHYSICSDensity-matrixElectronic correlationFermi-Dirac statisticsFull configuration interactionMean field theoryPerturbation theorySlater determinantStatistical thermodynamicsThermodynamic functions

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Gu, Pinhao [University of Illinois at Urbana-Champaign, IL (United States); University of Illinois at Urbana-Champaign] (ORCID:0009000011369485), Hirata, So [University of Illinois at Urbana-Champaign, IL (United States)] (ORCID:0000000295781502). 2024-12-04. Thermal mean-field theories. https://doi.org/10.1063/5.0235259

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