Category:DFT+U: Difference between revisions

Revision as of 18:53, 6 April 2022

Theoretical background

The semilocal LDA and GGA functionals often fail to describe systems with localized (strongly correlated) $d$ and $f$ -electrons (this manifests itself primarily in the form of unrealistic one-electron energies and too small magnetic moments). In some cases this can be remedied by introducing on the $d$ or $f$ atom a strong intra-atomic interaction in a simplified (screened) Hartree-Fock like manner, as an on-site replacement of the semilocal functional. This approach is commonly known as the DFT+U method^[1] (traditionally called LDA+U).

E_{\text{xc}}^{\text{LDA/GGA}+U}(n,\hat{n}) = E_{\text{xc}}^{\text{LDA/GGA}}(n,\hat{n}) + E_{\text{HF}}(\hat{n}) - E_{\text{dc}}(\hat{n})

How to

DFT+U can be used by specifying the tags LDAU and LDAUTYPE in the INCAR file.

↑ V. I. Anisimov, J. Zaanen, and O. K. Andersen, Phys. Rev. B 44, 943 (1991).

Pages in category "DFT+U"

The following 7 pages are in this category, out of 7 total.

D

DFT+U: formalism

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[anisimov:prb:91-1] V. I. Anisimov, J. Zaanen, and O. K. Andersen, Phys. Rev. B 44, 943 (1991).

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 == Theoretical background ==
-The semilocal LDA and GGA functionals often fail to describe systems with localized (strongly correlated) <math>d</math> and <math>f</math>-electrons (this manifests itself primarily in the form of unrealistic one-electron energies and too small magnetic moments). In some cases this can be remedied by introducing on the <math>d</math> or <math>f</math> atom a strong intra-atomic interaction in a simplified (screened) Hartree-Fock like manner, as an on-site replacement of the semilocal functional. This approach is commonly known as the DFT+U method{{cite|anisimov:prb:91|}} (traditionally called L(S)DA+U).
+The semilocal LDA and GGA functionals often fail to describe systems with localized (strongly correlated) <math>d</math> and <math>f</math>-electrons (this manifests itself primarily in the form of unrealistic one-electron energies and too small magnetic moments). In some cases this can be remedied by introducing on the <math>d</math> or <math>f</math> atom a strong intra-atomic interaction in a simplified (screened) Hartree-Fock like manner, as an on-site replacement of the semilocal functional. This approach is commonly known as the DFT+U method{{cite|anisimov:prb:91|}} (traditionally called LDA+U).
 :<math>E_{\text{xc}}^{\text{LDA/GGA}+U}(n,\hat{n}) = E_{\text{xc}}^{\text{LDA/GGA}}(n,\hat{n}) + E_{\text{HF}}(\hat{n}) - E_{\text{dc}}(\hat{n})</math>