Global hybrids from the semiclassical atom theory satisfying the local density linear response

TL;DR

This paper introduces a new class of global hybrid exchange-correlation functionals that align with the semiclassical atom theory, improve the local density approximation response, and outperform popular hybrids in diverse tests.

Contribution

The authors develop a robust hybrid functional, hAPBE, incorporating 20% Hartree-Fock exchange, that satisfies the semiclassical limit and enhances compatibility with correlation energies.

Findings

hAPBE performs better than PBE0 and B3LYP in various tests.

The new functional accurately reproduces the modified gradient expansion.

Broad tests confirm the robustness of the proposed hybrid functional.

Abstract

We propose global hybrid approximations of the exchange-correlation (XC) energy functional which reproduce well the modified fourth-order gradient expansion of the exchange energy in the semiclassical limit of many-electron neutral atoms and recover the full local density approximation (LDA) linear response. These XC functionals represent the hybrid versions of the APBE functional [Phys. Rev. Lett. 106, 186406, (2011)] yet employing an additional correlation functional which uses the localization concept of the correlation energy density to improve the compatibility with the Hartree-Fock exchange as well as the coupling-constant-resolved XC potential energy. Broad energetical and structural testings, including thermochemistry and geometry, transition metal complexes, non-covalent interactions, gold clusters and small gold-molecule interfaces, as well as an analysis of the hybrid parameters, show that our construction is quite robust. In particular, our testing shows that the resulting hybrid, including 20\% of Hartree-Fock exchange and named hAPBE, performs remarkably well for a broad palette of systems and properties, being generally better than popular hybrids (PBE0 and B3LYP). Semi-empirical dispersion corrections are also provided.