XANES and ELNES in Ceramic Science

Both X-ray absorption near edge structures (XANES) and electron energy loss near edge structure (ELNES) are important tools in ceramic science offering information on local environment of selected elements not only in crystals but also in amorphous materials. Recent technological progress enables measurements of XANES of ppm-level dopants using modern synchrotron facilities. Combined with transmission electron microscopy, ELNES can be used to analyze the local structures with subnanometer spatial resolution. First principles methods to reproduce and interpret the spectra have been established just recently. When a core-hole is adequately taken into account, most of K-edge spectra can be well reproduced using a modern band-structure method within one-electron approximation. The same is true for 1,2,3-edge spectra of non-transition metal compounds. However, multi-electron calculations are mandatory to reproduce 7-2,3-edge spectra of 3d transition-metal elements because of strong electronic correlations. In this paper, some recent results obtained in our group by the combination of XANES/ELNES experiments and theoretical calculations are reviewed.