Abstract: Compounds of 5d transition metals have been the subject of increasing study because they exhibit unique magnetic properties that can be attributed to strong spin-orbit coupling (SOC). In 5d metals, the energy associated with SOC is comparable to the Coulomb energy and the energy of crystal field stabilization. The correlation between these interactions can have an impact on various physical properties, such as the metal-dielectric transition of the Mott-Hubbard type, abnormal and spin Hall effects, the Rashba effect, the formation of skyrmions, and other effects related to Kitaev coupling The influence of the Jahn-Teller effect and spin-orbit coupling on the spatial and electronic structure of isolated octahedral complexes {MX6}n- (M = Rh, Pd, Re, Os, Ir, Pt, X = F, Cl, Br) and osmium compounds with realized exchange interactions (including OsCl4, OsO2, Li2OsO3, KOsO4, and K2OsO2(OH)4) was thoroughly investigated using quantum chemical calculations and X-ray absorption spectroscopy. The Os L3/L2 edge XANES spectra provided valuable information about the magnitude of the spin-orbit interaction by measuring the intensity ratio of the absorption edge lines. Moreover, the Cl and Br K-edge XANES spectra of transition metal compounds proved to be effective in studying the interaction between ligands and the central metal atom. Theoretical analysis of XANES spectra for Os compounds with different combinations of ligands and outer-sphere cations revealed that the electronic structure and magnetic properties are dependent on various factors, including the spin-orbit interaction, crystal field magnitude, electron pairing energy, and noncubic distortions of the Os environment. Acknowledgement: This work was supported by the Russian Science Foundation, grant 22-22-00683. This work was performed on equipment at the Siberian Center of Synchrotron and Terahertz Radiation based on the VEPP-4–VEPP-2000 Complex at the Budker Institute of Nuclear Physics. Our quantum chemical calculations were made using the resources of the Siberian Supercomputer Center at the Institute of Computational Mathematics and Mathematical Geophysics.

Cite: Fedorenko A.D. , Asanov I.P. , Asanova T.I. , Nikolenko A.D.
X-ray Absorption Spectroscopy Study on Spin-Orbit Interaction in Osmium Compounds
II International Conference «Synchrotron Radiation Techniques for Catalysts and Functional Materials» 23-27 Oct 2023