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Electron correlation effects and ferromagnetism in Iron

Pablo Pou·Fernando Flores·Jose Ortega·Ruben Perez·Alfredo Levy Yeyati
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Abstract

Electron correlation effects in Fe are analyzed using a first principles LCAO-scheme. In our approach, we first use a local orbital DFT-LDA solution to introduce a Hubbard Hamiltonian without fitting parameters. In a second step, we introduce a many-body solution to this Hamiltonian using a DMF approximation. Our analysis shows that magnetism in Fe is an effect associated with the first atomic Hund's rule. Moreover, we also find important correlation effects in the Fe-spin polarized DOS. The photoemision spectra is explained using a value of U_eff as large as 4 eV, provided the satellite peaks appearing around 3-5 eV below the Fermi energy are interpreted appropriately.

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Pablo Pou, Fernando Flores, Jose Ortega, Ruben Perez, Alfredo Levy Yeyati. 2001-12-03. Electron correlation effects and ferromagnetism in Iron. https://doi.org/10.1088/0953-8984%2F14%2F23%2F103

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