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LDA+Gutzwiller Method for Correlated Electron Systems

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 نشر من قبل Zhong Fang
 تاريخ النشر 2007
  مجال البحث فيزياء
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Combining the density functional theory (DFT) and the Gutzwiller variational approach, a LDA+Gutzwiller method is developed to treat the correlated electron systems from {it ab-initio}. All variational parameters are self-consistently determined from total energy minimization. The method is computationally cheaper, yet the quasi-particle spectrum is well described through kinetic energy renormalization. It can be applied equally to the systems from weakly correlated metals to strongly correlated insulators. The calculated results for SrVO$_3$, Fe, Ni and NiO, show dramatic improvement over LDA and LDA+U.



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