Initial Fermi orbital descriptors for FLOSIC calculations: The quick-FOD method

Nguyen, Duyen B.; Pederson, Mark R.; Perdew, John P.; Jackson, Koblar A.; Peralta, Juan E.

doi:10.1016/j.cplett.2021.138952

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Initial Fermi orbital descriptors for FLOSIC calculations: The quick-FOD method

Nguyen, Duyen B.·Pederson, Mark R.·Perdew, John P.·Jackson, Koblar A.·Peralta, Juan E.

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Abstract

Fermi orbital descriptors (FODs) play a key role in Fermi-Löwdin orbital self-interaction correction (FLOSIC) calculations used to remove self-interaction from approximate density functionals. Optimal FODs are obtained by minimizing the self-interaction-corrected total energy, and, in this process, identifying initial sets of FODs becomes crucial. Here we propose, implement and test a novel method for automatically initializing FODs, quick-FOD, based on the minimization of an empirical energy expression that involves a Coulomb-like FOD-electron density attraction, an FOD-FOD short-range repulsion, and an exchange-like FOD-density repulsion. Quick-FOD successfully reproduces FOD arrangements in qualitatively good agreement with Lewis theory and with full-fledged FLOSIC calculations.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS DFT FLOSIC FODs FODs generators

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Nguyen, Duyen B., Pederson, Mark R., Perdew, John P., Jackson, Koblar A., Peralta, Juan E.. 2021-08-05. Initial Fermi orbital descriptors for FLOSIC calculations: The quick-FOD method. https://doi.org/10.1016/j.cplett.2021.138952

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