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Curvilinear coordinates for full-core atoms

A. Putrino·G. B. Bachelet
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Abstract

Curvilinear coordinates, first introduced by F. Gygi for valence-only electronic systems within the local-density functional theory, can be used to describe both core and valence electrons in electronic-structure calculations. A simple and quite general coordinate transformation results in a large, yet affordable plane-wave energy cutoff for full-core systems (e.g., about 120 Ryd for carbon or silicon) within the local-density functional theory, and in a reduced correlation time for full-core variational Monte Carlo calculations. Numerical tests for isolated Li, C, and Si atoms are presented.

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A. Putrino, G. B. Bachelet. 1998-01-30. Curvilinear coordinates for full-core atoms. https://arxiv.org/abs/cond-mat/9801087

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