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Accuracy of density functionals for molecular electronics: the Anderson junction

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 نشر من قبل Zhenfei Liu
 تاريخ النشر 2012
  مجال البحث فيزياء
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The exact ground-state exchange-correlation functional of Kohn-Sham density functional theory yields the exact transmission through an Anderson junction at zero bias and temperature. The exact impurity charge susceptibility is used to construct the exact exchange-correlation potential. We analyze the successes and limitations of various types of approximations, including smooth and discontinuous functionals of the occupation, as well as symmetry-broken approaches.

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