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arXiv · 2609.12198

Pseudo-hybrid density functional ACBN0 for Hubbard $U$ correction in a numeric atom-centered orbital basis

Abstract

We present a formulation and implementation of the Agapito-Curtarolo-Buongiorno Nardelli (ACBN0) pseudo-hybrid density functional in a numeric atom-centered orbital basis. The method is realized in the all-electron, full-potential electronic-structure package FHI-aims. The implementation uses a Löwdin-orthogonalized projector, which improved the stability of the self-consistent ACBN0 iterations for the tested systems. For a benchmark set of materials including metal oxides and nitrides, ACBN0 with the fully localized limit (FLL) as the double-counting treatment reduces the aggregate band gap errors relative to the Perdew-Burke-Ernzerhof (PBE) and strongly constrained and appropriately normed (SCAN) functionals, reaching an accuracy comparable to the Heyd-Scuseria-Ernzerhof functional (HSE06). For six bulk transition metal oxides calculated with the same numerical settings, an HSE06 iteration is approximately 13-33 times as expensive as the corresponding ACBN0@PBE iteration with Petukhov mixing. The applicability of the localized-basis implementation to low-dimensional systems is demonstrated by calculations of adsorption and the oxygen evolution reaction (OER) overpotential on a $β$-NiOOH(001) surface. On regularized SCAN (rSCAN) relaxed structures, single point ACBN0 based on rSCAN (ACBN0@rSCAN) with the ``tight'' numerical settings reduces the mean absolute deviation of the reaction-step energies from HSE06 and shifts the estimated overpotential toward the HSE06 and Perdew-Burke-Ernzerhof hybrid (PBE0) reference results.

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BibTeXRIS

Svetlana A. Artiukova, Ilia M. Odud, Sergey V. Levchenko. 2026-09-10. Pseudo-hybrid density functional ACBN0 for Hubbard $U$ correction in a numeric atom-centered orbital basis. https://arxiv.org/abs/2609.12198

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