Orbital magnetic moments in FeCrS studied by X-ray magnetic circular dichroism

Verma, V. K.*; 芝田 悟朗 ; 藤森 淳*; 他8名*

Verma, V. K.*; Shibata, Goro; Fujimori, Atsushi*; 8 of others*

We have investigated the element specific magnetic characteristics of single-crystal FeCrS using X-ray magnetic circular dichroism (XMCD). We have found that the Fe L2,3-edge XAS spectra do not exhibit clear multiplet structures, indicating strong hybridization between the Fe 3d and S 3p orbitals, leading to delocalized rather than localized electronic states. The Fe 3d and Cr 3d spin moments are antiferromagnetically coupled, consistent with the Goodenough-Kanamori rule. The orbital magnetic moments of Fe and Cr are determined to be -0.23 and -0.017 B/ion, respectively. The large orbital magnetic moment of Fe is due to the d6 configuration under the relatively weak tetrahedra crystal field at the Fe site, and the delocalized Fe electrons maintain the orbital degree of freedom in spite of their itinerant nature. On the other hand, the octahedral crystal-field splitting of the Cr 3d level is large enough to result in the quenching of the orbital moment of the Cr ion in FeCrS.