Magnetic circular x-ray dichroism and its relation to local moments

The study of magnetic XANES of circularly polarized X-rays at the K-edges and the L-edges in 3d-, 4/- and 5d-elements in ferro(i)magnetic materials is a powerful method to investigate in an element-selective manner magnetic aspects of the electronic structure of solids. It is demonstrated on the basis of simplified single-particle band-structure pictures that for 3d- and 5d-elements, which are polarized by 3d-neighbors, information on the local spin and orbital moments can be directly deduced from the magnetic L2 3-spectra similar to the application of the sum rules recently developed by T. Thole and P. Carra. Spin-polarized EXAFS studies of various systems are presented demonstrating the sensitivity of the SPEXAFS to the magnetic neighborhood only and their direct correlation to magnetic moments of neighboring atoms.