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arXiv · 1501.07105

Comparison between exact and semilocal exchange potentials: An all-electron study for solids

Fabien Tran·Markus Betzinger·Peter Blaha·Stefan Blügel
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Abstract

The exact-exchange (EXX) potential, which is obtained by solving the optimized-effective potential (OEP) equation, is compared to various approximate semilocal exchange potentials for a set of selected solids (C, Si, BN, MgO, Cu$_{2}$O, and NiO). This is done in the framework of the linearized augmented plane-wave method, which allows for a very accurate all-electron solution of electronic structure problems in solids. In order to assess the ability of the semilocal potentials to approximate the EXX-OEP, we considered the EXX total energy, electronic structure, electric-field gradient, and magnetic moment. An attempt to parameterize a semilocal exchange potential is also reported.

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Fabien Tran, Markus Betzinger, Peter Blaha, Stefan Blügel. 2015-01-28. Comparison between exact and semilocal exchange potentials: An all-electron study for solids. https://doi.org/10.1103/physrevb.91.165121

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