Self-consistent energy approximation for orbital-free density-functional theory

E. Rasanen; A. Odriazola; I. Makkonen; A. Harju

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arXiv · 1310.8113

Self-consistent energy approximation for orbital-free density-functional theory

E. Rasanen·A. Odriazola·I. Makkonen·A. Harju

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Abstract

Employing a local formula for the electron-electron interaction energy, we derive a self-consistent approximation for the total energy of a general $N$-electron system. Our scheme works as a local variant of the Thomas-Fermi approximation and yields the total energy and density as a function of the external potential, the number of electrons, and the chemical potential determined upon normalization. Our tests for Hooke's atoms, jellium, and model atoms up to $\sim 1000$ electrons show that reasonable total energies can be obtained with almost a negligible computational cost. The results are also consistent in the important large-$N$ limit.

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E. Rasanen, A. Odriazola, I. Makkonen, A. Harju. 2013-10-30. Self-consistent energy approximation for orbital-free density-functional theory. https://arxiv.org/abs/1310.8113

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