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Review of approximations for the exchange-correlation energy in density-functional theory

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 نشر من قبل Julien Toulouse
 تاريخ النشر 2021
  مجال البحث فيزياء
والبحث باللغة English
 تأليف Julien Toulouse




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In this chapter, we provide a review of ground-state Kohn-Sham density-functional theory of electronic systems and some of its extensions, we present exact expressions and constraints for the exchange and correlation density functionals, and we discuss the main families of approximations for the exchange-correlation energy: semilocal approximations, single-determinant hybrid approximations, multideterminant hybrid approximations, dispersion-corrected approximations, as well as orbital-dependent exchange-correlation density functionals. The chapter aims at providing both a consistent birds-eye view of the field and a detailed description of some of the most used approximations. It is intended to be readable by chemists/physicists and applied mathematicians.



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