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The effect of double counting, spin density, and Hund interaction in the different DFT+U functionals.

ABSTRACT: A systematic comparative study has been performed to better understand DFT+U (density functional theory?+?U) method. We examine the effect of choosing different double counting and exchange-correlation functionals. The calculated energy distribution and the Hund-J dependence of potential profile for representative configurations clearly show the different behaviors of each DFT+U formalism. In particular, adopting spin-dependent exchange-correlation functionals likely leads to undesirable magnetic solution. Our analyses are further highlighted by real material examples ranging from insulating oxides (MnO and NiO) to metallic magnetic systems (SrRuO₃ and BaFe₂As₂). The current work sheds new light on understanding DFT+U and provides a guideline to use the related methods.

SUBMITTER: Ryee S

PROVIDER: S-EPMC6015075 | biostudies-literature | 2018 Jun

REPOSITORIES: biostudies-literature

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The effect of double counting, spin density, and Hund interaction in the different DFT+U functionals.

Ryee Siheon S Han Myung Joon MJ

Scientific reports 20180622 1

A systematic comparative study has been performed to better understand DFT+U (density functional theory + U) method. We examine the effect of choosing different double counting and exchange-correlation functionals. The calculated energy distribution and the Hund-J dependence of potential profile for representative configurations clearly show the different behaviors of each DFT+U formalism. In particular, adopting spin-dependent exchange-correlation functionals likely leads to undesirable magneti ...[more]

PMID: 29934623

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