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arXiv · 1911.10813

Parameter-free hybrid functional based on an extended Hubbard model: DFT+U+V

Nicolas Tancogne-Dejean·Angel Rubio
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Abstract

In this article, we propose an energy functional at the level of DFT+U+V that allows us to compute self-consistently the values of the on-site interaction, Hubbard U and Hund J, as well as the intersite interaction V. This functional extends the previously proposed ACBN0 functional [Phys. Rev. X 5, 011006 (2015)] including both on-site and intersite interactions. We show that this ab initio self-consistent functional yields improved electronic properties for a wide range of materials, ranging from $sp$ materials to strongly-correlated materials. This functional can also be seen as an alternative general and systematic way to construct parameter-free hybrid functionals, based on the extended Hubbard model and a selected set of Coulomb integrals, and might be used to develop novel approximations. By extending the DFT+U method to materials where strong local and nonlocal interactions are relevant, this work opens the door to the ab initio study the electronic, ionic, and optical properties of a larger class of strongly correlated materials in and out of equilibrium.

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Nicolas Tancogne-Dejean, Angel Rubio. 2020-09-21. Parameter-free hybrid functional based on an extended Hubbard model: DFT+U+V. https://doi.org/10.1103/physrevb.102.155117

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