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The many-body exchange-correlation hole at metal surfaces

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 نشر من قبل Lucian Constantin
 تاريخ النشر 2009
  مجال البحث فيزياء
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We present a detailed study of the coupling-constant-averaged exchange-correlation hole density at a jellium surface, which we obtain in the random-phase approximation (RPA) of many-body theory. We report contour plots of the exchange-only and exchange-correlation hole densities, the integration of the exchange-correlation hole density over the surface plane, the on-top correlation hole, and the energy density. We find that the on-top correlation hole is accurately described by local and semilocal density-functional approximations. We also find that for electrons that are localized far outside the surface the main part of the corresponding exchange-correlation hole is localized at the image plane.

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