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Orbital ordering in the two-dimensional ferromagnetic semiconductor Rb_2CrCl_4

Udo Schwingenschloegl·Volker Eyert
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Abstract

We present the results of electronic structure calculations for the two-dimensional ferromagnet Rb_2CrCl_4. They are obtained by the augmented spherical wave method as based on density functional theory and the local density approximation. In agreement with experimental data Rb_2CrCl_4 is found to be semiconducting and displays long-range ferromagnetic order of the localized Cr 3d moments. The magnetic properties are almost independent of the structural modifications arising from the Jahn-Teller instability, which leads from the parent body-centered tetragonal K_2NiF_4 structure to a side-centered orthorhombic lattice. In contrast, our calculations give evidence for a strong response of the optical band gap to the corresponding structural changes.

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Udo Schwingenschloegl, Volker Eyert. 2005-10-12. Orbital ordering in the two-dimensional ferromagnetic semiconductor Rb_2CrCl_4. https://doi.org/10.1016/j.jmmm.2006.10.1093

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