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X-ray absorption and x-ray magnetic dichroism study on Ca(3)CoRhO(6) and Ca(3)FeRhO(6)

Physical review. B, Condensed matter (Impact Factor: 3.77). 04/2008; 77. DOI: 10.1103/PhysRevB.77.205111
Source: arXiv

ABSTRACT By using x-ray absorption spectroscopy at the Rh L(2,3), Co L(2,3), and Fe L(2,3) edges, we find a valence state of Co(2+)/Rh(4+) in Ca(3)CoRhO(6) and of Fe(3+)/Rh(3+) in Ca(3)FeRhO(6). X-ray magnetic circular dichroism spectroscopy at the Co L(2,3) edge of Ca(3)CoRhO(6) reveals a giant orbital moment of about 1.7 mu(B), which can be attributed to the occupation of the minority-spin d(0)d(2) orbital state of the high-spin Co(2+) (3d(7)) ions in trigonal prismatic coordination. This active role of the spin-orbit coupling explains the strong magnetocrystalline anisotropy and Ising-type magnetism of Ca(3)CoRhO(6).

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