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arXiv · 1207.5923

Quasi-non-local gradient-level exchange-correlation approximation for metals and alloys

H. Levämäki·L. Vitos·M. P. J. Punkkinen·K. Kokko
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Abstract

The flexibility of common generalized gradient approximation for the exchange-correlation energy is investigated by monitoring the equilibrium volume of transition metals. It is shown that no universal gradient-level approximation yielding consistent errors for all metals exists. Based on an element-specific optimization, the concept of quasi-non-local gradient-level approximation is introduced. The strength of the scheme is demonstrated on several transition metal alloys.

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H. Levämäki, L. Vitos, M. P. J. Punkkinen, K. Kokko. 2012-07-25. Quasi-non-local gradient-level exchange-correlation approximation for metals and alloys. https://doi.org/10.1103/physrevb.86.201104

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