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DOE OSTI · 2409382

Exchange correlation potentials from full configuration interaction in a Slater orbital basis

Tribedi, Soumi·Dang, Duy-Khoi·Kanungo, Bikash·Gavini, Vikram·Zimmerman, Paul M.
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Abstract

Ryabinkin–Kohut–Staroverov (RKS) theory builds a bridge between wave function theory and density functional theory by using quantities from the former to produce accurate exchange-correlation potentials needed by the latter. In this work, the RKS method is developed and tested alongside Slater atomic orbital basis functions for the first time. To evaluate this approach, full configuration interaction computations in the Slater orbital basis are employed to give quality input to RKS, allowing full correlation to be present along with correct nuclei cusps and asymptotic decay of the wavefunction. SlaterRKS is shown to be an efficient algorithm to arrive at exchange-correlation potentials without unphysical artifacts in moderately-sized basis sets. Furthermore, enforcement of the nuclear cusp conditions will be shown to be vital for the success of the Slater-basis RKS method. As a result, examples of weakly and strongly correlated molecular systems will demonstrate the main features of SlaterRKS.

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74 ATOMIC AND MOLECULAR PHYSICSBasis setsChemical bondingCorrelation energyCoulomb integralDensity functional theoryDensity-matrixFull configuration interactionOpenMP

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Tribedi, Soumi, Dang, Duy-Khoi, Kanungo, Bikash, Gavini, Vikram, Zimmerman, Paul M.. 2023-08-02. Exchange correlation potentials from full configuration interaction in a Slater orbital basis. https://doi.org/10.1063/5.0157942

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