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Model Hamiltonian parameters for half-metallic ferromagnets NiMnSb and CrO2

A. Yamasaki·L. Chioncel·A. I. Lichtenstein·O. K. Andersen
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Abstract

Using the recently developed Nth-order muffin-tin-orbital (NMTO) based downfolding technique we revisit the electronic properties of half-metallic ferromagnets, the semi-Heusler NiMnSb and rutile CrO2. The NMTO Wannier orbitals for the Mn-d and Cr-t2g manifolds are constructed and the mechanism of chemical bonding is discussed. The effective hopping Hamiltonian parameters are calculated using a NMTO downfolded basis set. We propose model Hamiltonian parameters with possibly minimal basis sets for both half-metallic ferromagnetic alloys.

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A. Yamasaki, L. Chioncel, A. I. Lichtenstein, O. K. Andersen. 2006-07-23. Model Hamiltonian parameters for half-metallic ferromagnets NiMnSb and CrO2. https://doi.org/10.1103/physrevb.74.024419

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