Issues and Challenges in Orbital-free Density Functional Calculations

V. V. Karasiev; S. B. Trickey

doi:10.1016/j.cpc.2012.06.016

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arXiv · 1109.6602

Issues and Challenges in Orbital-free Density Functional Calculations

V. V. Karasiev·S. B. Trickey

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Abstract

Solving the Euler equation which corresponds to the energy minimum of a density functional expressed in orbital-free form involves related but distinct computational challenges. One is the choice between all-electron and pseudo-potential calculations and, if the latter, construction of the pseudo-potential. Another is the stability, speed, and accuracy of solution algorithms. Underlying both is the fundamental issue of satisfactory quality of the approximate functionals (kinetic energy and exchange-correlation). We address both computational issues and illustrate them by some comparative performance testing of our recently developed modified-conjoint generalized gradient approximation kinetic energy functionals. Comparisons are given for atoms, diatomic molecules, and some simple solids.

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V. V. Karasiev, S. B. Trickey. 2012-06-04. Issues and Challenges in Orbital-free Density Functional Calculations. https://doi.org/10.1016/j.cpc.2012.06.016

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