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arXiv · 2005.03383

Exchange-correlation corrections for electronic properties of half-metallic Co$_2$FeSi and nonmagnetic semiconductor CoFeTiAl

Olga N. Miroshkina·Danil R. Baigutlin·Vladimir V. Sokolovskiy·Mikhail A. Zagrebin·Aki Pulkkinen·Bernardo Barbiellini·Erkki Lähderanta·Vasiliy D. Buchelnikov
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Abstract

We consider two cobalt-based full-Heusler compounds CoFeTiAl and Co$_2$FeSi, for which Coulomb correlation effects play an important role. Since the standard GGA scheme does not provide a precise description of the electronic properties near the Fermi level, we use a meta-GGA functional capable to improve the description of the electronic properties of CoFeTiAl and Co$_2$FeSi. In particular, we find a better agreement with the experiment for the magnetic moment and the energy-band gap. Moreover, our calculations show that pressure enhances the insulating properties of Co$_2$FeSi and CoTiFeAl.

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Olga N. Miroshkina, Danil R. Baigutlin, Vladimir V. Sokolovskiy, Mikhail A. Zagrebin, Aki Pulkkinen, Bernardo Barbiellini, Erkki Lähderanta, Vasiliy D. Buchelnikov. 2020-05-07. Exchange-correlation corrections for electronic properties of half-metallic Co$_2$FeSi and nonmagnetic semiconductor CoFeTiAl. https://doi.org/10.1063/5.0006201

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