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arXiv · 1406.2944

Theoretical unification of hybrid-DFT and DFT+U methods for the treatment of localized orbitals

Viktor Ivády·Rickard Armiento·Krisztián Szász·Erik Janzén·Adam Gali·Igor A. Abrikosov
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Abstract

We formulate the on-site occupation dependent exchange correlation energy and effective potential of hybrid functionals for localized states and connect them to the on-site correction term of the DFT+U method. Our derivation provides a theoretical justification for adding a DFT+U-like onsite potential in hybrid DFT calculations to resolve issues caused by overscreening of localized states. The resulting scheme, hybrid- DFT+Vw, is tested for chromium impurity in wurtzite AlN and vanadium impurity in 4H-SiC, which are paradigm examples of systems with different degree of localization between host and impurity orbitals.

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Viktor Ivády, Rickard Armiento, Krisztián Szász, Erik Janzén, Adam Gali, Igor A. Abrikosov. 2014-06-11. Theoretical unification of hybrid-DFT and DFT+U methods for the treatment of localized orbitals. https://doi.org/10.1103/physrevb.90.035146

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