5d-level energies of Ce3+ and the crystalline environment. IV. Aluminates and “simple” oxides

Information on the energy of 5d-levels of Ce3+ ions in aluminates and “simple” oxides has been collected. The crystal field splitting of the 5d-levels is interpreted in terms of the type and size of anion polyhedron coordinating the Ce3+ ion. The centroid (barycenter) shift of the 5d-configuration is analyzed by a ligand polarization model providing values for the spectroscopic polarizability αsp of the anion ligands. The data provide evidence that the centroid shift behaves independently from the crystal field splitting. By combining centroid shift and crystal field splitting, the “spectroscopic” redshift of the first electric dipole-allowed fd transition of Ce3+-doped in the compounds will be interpreted. The large crystal field splitting in garnet compounds and the small splitting in perovskite compounds will be discussed.