Abstract
By using x-ray absorption spectroscopy at the , , and edges, we find a valence state of in and of in . X-ray magnetic circular dichroism spectroscopy at the edge of reveals a giant orbital moment of about , which can be attributed to the occupation of the minority-spin orbital state of the high-spin ions in trigonal prismatic coordination. This active role of the spin-orbit coupling explains the strong magnetocrystalline anisotropy and Ising-type magnetism of .
- Received 3 March 2008
DOI:https://doi.org/10.1103/PhysRevB.77.205111
©2008 American Physical Society