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Rigorous body-order approximations of an electronic structure potential energy landscape

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 نشر من قبل Jack Thomas
 تاريخ النشر 2021
  مجال البحث فيزياء
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We show that the local density of states (LDOS) of a wide class of tight-binding models has a weak body-order expansion. Specifically, we prove that the resulting body-order expansion for analytic observables such as the electron density or the energy has an exponential rate of convergence both at finite Fermi-temperature as well as for insulators at zero Fermi-temperature. We discuss potential consequences of this observation for modelling the potential energy landscape, as well as for solving the electronic structure problem.



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