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Non-linear density functional theory: A direct method to calculate many-electron charge densities

Werner A. Hofer·Krisztian Palotas
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Abstract

We suggest to include the density of electron charge explicitly in the electron potential of density functional theory, rather than implicitly via exchange-correlation functionals. The advantages of the approach are conceptual and numerical. Conceptually, it allows to formulate a physical principle for the development of quantum mechanical systems: it is the principle of energetic equilibrium, because the energy principle, in this case, applies not only globally, but also on a local level. The method is an order-$N$ method, scaling linearly with the number of atoms. It is used to calculate the electronic groundstate of a metallic surface, where we find good agreement with experimental values.

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Werner A. Hofer, Krisztian Palotas. 2005-10-25. Non-linear density functional theory: A direct method to calculate many-electron charge densities. https://arxiv.org/abs/cond-mat/0508516

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