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arXiv · 2004.12689

Efficient yet Accurate Dispersion-Corrected Semilocal Exchange-Correlation Functionals For Non-Covalent Interactions

Abstract

Due to several attractive features, the meta-generalized-gradient approximations (meta-GGAs) are considered to be the most advanced and potentially accurate semilocal exchange-correlation functionals in the rungs of the Jacob's ladder of Density Functional Theory. So far, several meta-GGA are proposed by fitting to the test sets or/and satisfying as many as known exact constraints. Although the density overlap is treated by modern meta-GGA functionals efficiently, for non-covalent interactions, a long-range dispersion correction is essential. In this work, we assess the benchmark performance of different variants of the Tao-Mo semilocal functional (i.e. TM of Phys. Rev. Lett. 117, 073001 (2016) and revTM of J. Phys. Chem. A 123, 6356 (2019)) with Grimme's D3 correction for the several non-covalent interactions, including dispersion and hydrogen bonded systems. We consider the zero, Becke-Johnson(BJ), and optimized power (OP) damping functions within the D3 method, with both TM and revTM functionals. It is observed that the overall performance of the functionals gradually improved from zero to BJ and to OP damping. However, the constructed "OP" corrected (rev)TM+D3(OP) functionals perform considerably better compared to other well-known dispersion corrected functionals. Based on the accuracy of the proposed functionals, the future applicability of these methods is also discussed.

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BibTeXRIS

Abhilash Patra, Subrata Jana, Lucian A. Constantin, Prasanjit Samal. 2020-04-27. Efficient yet Accurate Dispersion-Corrected Semilocal Exchange-Correlation Functionals For Non-Covalent Interactions. https://arxiv.org/abs/2004.12689

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