4f and 5d levels of Ce3+ in D2 eightfold oxygen coordination

摘要

The effects on the 4f and 5d levels of Ce3+ of its first coordination shellgeometry in Ce-doped oxides with a D2 8-fold site, like garnets, are studiedwith embedded cluster, wave function based ab initio methods. The onlydeformations of a CeO8 cube that are found to shift the lowest 4f-5d transitionto the red are the symmetric Ce-O bond compression and the tetragonal symmetricbond bending. These results are analyzed in terms of centroid and ligand fieldstabilization energy differences. The splittings of the upper 5d levels and ofthe 4f levels are also discussed.