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arXiv · 1411.1579

Gradient-dependent upper bound for the exchange-correlation energy and application to density functional theory

L. A. Constantin·E. Fabiano·A. Terentjevs·F. Della Sala
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Abstract

We propose a simple gradient-dependent bound for the exchange-correlation energy (sLL), based on the recent non-local bound derived by Lewin and Lieb. We show that sLL is equivalent to the original Lieb-Oxford bound in rapidly-varying density cases but it is tighter for slowly-varying density systems. To show the utility of the sLL bound we apply it to the construction of simple semilocal and non-local exchange and correlation functionals. In both cases improved results, with respect to the use of Lieb-Oxford bound, are obtained showing the power of the sLL bound.

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L. A. Constantin, E. Fabiano, A. Terentjevs, F. Della Sala. 2015-01-21. Gradient-dependent upper bound for the exchange-correlation energy and application to density functional theory. https://doi.org/10.1103/physrevb.91.041120

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