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arXiv · 2408.06038

Modelling the Kohn-Sham potential for molecular dissociation with orbital-independent functionals: a proof of principle

Sara Giarrusso·Federica Agostini
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Abstract

We model the Hartree-exchange-correlation potential of Kohn-Sham density-functional theory adopting a novel strategy inspired by the strictly-correlated-electrons limit and relying on the exact decomposition of the potential based on the exact factorization formalism. Starting with accurate density and conditional potential for a one-dimensional model of a stretched heteronuclear molecule, we provide a proof-of-principle example of an approximation that accurately reproduces the step of the exact Kohn-Sham potential without resorting to the Kohn-Sham orbitals, virtual or occupied. We also test our strategy using the approximate conditional potentials corresponding to the strictly-correlated-electron and the exact-exchange functionals. The results are encouraging in that the initial approximations are modified in the qualitatively correct way: decreasing correlation in the former and increasing it in the latter.

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Sara Giarrusso, Federica Agostini. 2024-08-12. Modelling the Kohn-Sham potential for molecular dissociation with orbital-independent functionals: a proof of principle. https://arxiv.org/abs/2408.06038

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