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arXiv · 2401.12035

The origin of magnetism in a supposedly nonmagnetic osmium oxide

S. Agrestini·F. Borgatti·P. Florio·J. Frassineti·D. Fiore Mosca·Q. Faure·B. Detlefs·C. J. Sahle·S. Francoual·J. Choi·M. Garcia-Fernandez·K. -J. Zhou·V. F. Mitrovic·P. M. Woodward·G. Ghiringhelli·C. Franchini·F. Boscherini·S. Sanna·and M. Moretti Sala
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Abstract

A supposedly nonmagnetic 5d$^1$ double perosvkite oxide is investigated by a combination of spectroscopic and theoretical methods, namely resonant inelastic X-ray scattering, X-ray absorption spectroscopy, magnetic circular dichroism, and multiplet ligand field calculations. We found that the large spin-orbit coupling admixes the 5d $t_{2g}$ and $e_g$ orbitals, covalency raises the 5d population well above the nominal value, and the local symmetry is lower than $O_h$. The obtained electronic interactions account for the finite magnetic moment of Os in this compound and, in general, of 5d$^1$ ions. Our results provide direct evidence of elusive Jahn-Teller distortions, hinting at a strong electron-lattice coupling.

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S. Agrestini, F. Borgatti, P. Florio, J. Frassineti, D. Fiore Mosca, Q. Faure, B. Detlefs, C. J. Sahle, S. Francoual, J. Choi, M. Garcia-Fernandez, K. -J. Zhou, V. F. Mitrovic, P. M. Woodward, G. Ghiringhelli, C. Franchini, F. Boscherini, S. Sanna, and M. Moretti Sala. 2024-01-22. The origin of magnetism in a supposedly nonmagnetic osmium oxide. https://doi.org/10.1103/physrevlett.133.066501

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