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Numerical atomic orbitals for linear scaling

Javier Junquera·Oscar Paz·Daniel Sanchez-Portal·Emilio Artacho
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Abstract

The performance of basis sets made of numerical atomic orbitals is explored in density-functional calculations of solids and molecules. With the aim of optimizing basis quality while maintaining strict localization of the orbitals, as needed for linear-scaling calculations, several schemes have been tried. The best performance is obtained for the basis sets generated according to a new scheme presented here, a flexibilization of previous proposals. The basis sets are tested versus converged plane-wave calculations on a significant variety of systems, including covalent, ionic and metallic. Satisfactory convergence (deviations significantly smaller than the accuracy of the underlying theory) is obtained for reasonably small basis sizes, with a clear improvement over previous schemes. The transferability of the obtained basis sets is tested in several cases and it is found to be satisfactory as well.

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Javier Junquera, Oscar Paz, Daniel Sanchez-Portal, Emilio Artacho. 2001-04-10. Numerical atomic orbitals for linear scaling. https://doi.org/10.1103/physrevb.64.235111

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