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arXiv · 2205.09568

Orbital-slective behaviour in cubanite CuFe2S3

E. A. Pankrushina·A. V. Ushakov·M. M. Abd-Elmeguid·S. V. Streltsov
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Abstract

Using {\it ab initio} band structure calculations we show that mineral cubanite, CuFe$_2$S$_3$, demonstrates an orbital-selective behavior with some of the electrons occupying molecular orbitals of $x^2-y^2$ symmetry and others localized at atomic orbitals. This is a rare situation for $3d$ transition metal compounds explains experimentally observed absence of charge disproportionation, anomalous M\"ossbauer data, and ferromagnetic ordering in between nearest neighbor Fe ions.

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E. A. Pankrushina, A. V. Ushakov, M. M. Abd-Elmeguid, S. V. Streltsov. 2022-05-19. Orbital-slective behaviour in cubanite CuFe2S3. https://doi.org/10.1103/physrevb.105.024406

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