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arXiv · 2106.12572

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

Jack Thomas·Huajie Chen·Christoph Ortner
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Abstract

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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Jack Thomas, Huajie Chen, Christoph Ortner. 2021-06-23. Rigorous body-order approximations of an electronic structure potential energy landscape. https://doi.org/10.1007/s00205-022-01809-w

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