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arXiv · 1710.06032

Deorbitalization strategies for meta-GGA exchange-correlation functionals

Daniel Mejia-Rodriguez·S. B. Trickey
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Abstract

We explore the simplification of widely used meta-generalized-gradient approximation (mGGA) exchange-correlation functionals to the Laplacian level of refinement by use of approximate kinetic energy density functionals (KEDFs). Such deorbitalization is motivated by the prospect of reducing computational cost while recovering a strictly Kohn-Sham local potential framework (rather than the usual generalized Kohn-Sham treatment of mGGAs). A KEDF that has been rather successful in solid simulations proves to be inadequate for deorbitalization but we produce other forms which, with parametrization to Kohn-Sham results (not experimental data) on a small training set, yield rather good results on standard molecular test sets when used to deorbitalize the meta-GGA made very simple, TPSS, and SCAN functionals. We also study the difference between high-fidelity and best-performing deorbitalizations and discuss possible implications for use in ab initio molecular dynamics simulations of complicated condensed phase systems.

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Daniel Mejia-Rodriguez, S. B. Trickey. 2017-10-16. Deorbitalization strategies for meta-GGA exchange-correlation functionals. https://doi.org/10.1103/physreva.96.052512

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