“…Since R c > 9.4 Å of the unit cell length, the energy transfer for the Tb 3+ ions can be ascribed to multipole-multipole interactions. For the case of Pr 3+ doped samples, the theoretical emission bands should be found at 487, 530, 604, 620, 648, 706, and 728 nm for the emission of 3 P 0 -3 H 4 , 3 P 0,1 -3 H 5 , 1 D 2 -3 H 4 , 3 P 0 -3 H 6 , 3 P 0 -3 F 2 , 1 D 2 -3 H 5 , and 3 P 0 -3 F 3 + 3 F 4 , respectively [87]. In our Pr 3+ doped samples, although most of the theoretical emission peaks could also be observed (Figure S22), no separated peaks could be found, which could be ascribed to the internal energy transitions resulted from of thermally induced expansion of emission cross section of Pr 3+ according to Judd-Ofelt theory [88].…”