A role of Gd3+ in scintillating processes in Tb-doped Na–Gd phosphate glasses

Sensitization role of Gd3+ ions in energy transfer processes in radio- and photo-luminescence is described for Tb3+-doped and Gd-enriched NaxGdy phosphate glasses. Limited (Gd–Gd)n energy migration is obtained and the Gd3+→Tb3+ transfer is explained as due to mainly the (super) exchange interaction. These results are discussed and compared with the situation observed in similar glasses or crystals where transfer processes are mainly due to multi-polar interaction (Gd3+→Ce3+ or Ce3+→Gd3+) and more efficient migration among Gd3+ ions that is observed.