paper

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

arXiv:2609.12198

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). The computational cost of a single ACBN0 self-consistent-field iteration is comparable to that of the parent functional and substantially lower than that of HSE06. The applicability of the localizedbasis implementation to low-dimensional systems is demonstrated by calculations of adsorption and the oxygen evolution reaction (OER) overpotential on a -NiOOH(001) surface. On structures relaxed with regularized SCAN (rSCAN), single-point ACBN0 calculations based on rSCAN (ACBN0@rSCAN) with the "tight" numerical settings reduce the mean absolute deviation of the reaction-step energies from HSE06 and shift the estimated overpotential toward the HSE06 and Perdew-Burke-Ernzerhof hybrid (PBE0) reference results.

arXiv comment33 pages, 8 figures