Structural effects on the emission dynamics of oxide crystals activated with Tb3+

Flux grown crystals of YPO4, GdPO4, LaPO4, CaWO4, CaMoO4, KLa(MoO4)2, GdAl3(BO3)4, and GdTa7O19 activated with Tb3+ have been comparatively characterized by Raman and luminescence spectroscopy in order to investigate the relation between structural and emission properties. Processes like host sensitization, Tb3+- Tb3+ energy transfer, formation of charge transfer states, etc., as well as their effects on the emission dynamics have been examined in the light of the spatial distribution of the involved centers. The analysis of the experimental results allows to evidence the role of the site symmetry of the active ions, of their distribution inside the lattice, of their interactions with the vibrational and electronic structure of the host, and provide useful information for understanding the luminescence properties and for the design of new Tb3+-doped materials.