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Construction of the B88 Exchange-Energy Functional in Two Dimensions
J G Vilhena1,2, E Räsänen3, M A L Marques4
1Instituto de Ciencia de Materiales de Madrid, CSIC 28049 Madrid, Spain.
Abstract:
We construct a generalized-gradient approximation for the exchange-energy density of finite two-dimensional systems. Guided by nonempirical principles, we include the proper small-gradient limit and the proper tail for the exchange-hole potential. The observed performance is superior to that of the two-dimensional local-density approximation, which underlines the usefulness of the approach in practical applications.
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