Abstract

We show that the Kohn-Sham positive-definite kinetic energy (KE) density significantly differs from the von Weizsäcker (VW) one at the nuclear cusp as well as in the asymptotic region. At the nuclear cusp, the VW functional is shown to be linear, and the contribution of p-type orbitals to the KE density is theoretically derived and numerically demonstrated in the limit of infinite nuclear charge as well in the semiclassical limit of neutral large atoms. In the latter case, it reaches 12% of the KE density. In the asymptotic region we find new exact constraints for meta-generalized gradient approximation (meta-GGA) exchange functionals: with an exchange enhancement factor proportional to ?--?, where ? is the common meta-GGA ingredient, both the exchange energy density and the potential are proportional to the exact ones. In addition, this describes exactly the large-gradient limit of quasi-two-dimensional systems.

Autore Pugliese

• Fabiano Eduardo , Della Sala Fabio

Tutti gli autori

• F. Della Sala; E. Fabiano; L. A. Constantin

Titolo volume/Rivista

Physical review. B, Solid state

Anno di pubblicazione

2015

ISSN

0556-2805

ISBN

Non Disponibile

Numero di citazioni Wos

Nessuna citazione

Ultimo Aggiornamento Citazioni

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Numero di citazioni Scopus

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Ultimo Aggiornamento Citazioni

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Settori ERC

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Codici ASJC

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