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arXiv · 1111.6470

Large two-dimensional electronic systems: Self-consistent energies and densities at low cost

E. Rasanen·S. Pittalis·G. Bekcioglu·I. Makkonen
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Abstract

We derive a self-consistent local variant of the Thomas-Fermi approximation for (quasi-)two-dimensional (2D) systems by localizing the Hartree term. The scheme results in an explicit orbital-free representation of the electron density and energy in terms of the external potential, the number of electrons, and the chemical potential determined upon normalization. We test the method over a variety 2D nanostructures by comparing to the Kohn-Sham 2D-LDA calculations up to 600 electrons. Accurate results are obtained in view of the negligible computational cost. We also assess a local upper bound for the Hartree energy.

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E. Rasanen, S. Pittalis, G. Bekcioglu, I. Makkonen. 2013-01-09. Large two-dimensional electronic systems: Self-consistent energies and densities at low cost. https://doi.org/10.1103/physrevb.87.035144

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