The structural and scintillation properties of pure and Ce-doped Y 3 Sc x Al 5 − x O 12 ( x = 0 , 0.05 , 1.16 , and 2 ) crystals were systematically investigated. High-resolution Sc 45 and Al 27 magic angle spinning nuclear magnetic resonance spectroscopy revealed that S c 3 + ions predominantly occupy octahedral sites, effectively replacing A l 3 + ions, while antisite Sc at Y dodecahedral positions remains below 0.2 at.%. Sc incorporation into Y 3 Al 5 O 12 induces strong exciton emission at 320–324 nm, nearly 10 times higher than that of reference Bi 4 Ge 3 O 12 (BGO) crystal, even at low Sc concentrations (5 at.%). C e 3 + doping introduces characteristic 5 d 1 → 4 f emission at 518 nm, accelerates scintillation decay, and in combination with M g 2 + codoping, promotes the formation of C e 4 + ions that enable a fast radiative de-excitation pathway. Y 3 Sc 2 Al 3 O 12 : Ce exhibits a maximum scintillation light yield of 80–84% relative to BGO with a mean decay time of 85–110 ns. Thermostimulated liminescence and electron paramagnetic resonance studies indicate that holes are mainly trapped at oxygen ions near Sc ions ( O − centers), while electrons are primarily localized at Sc antisite ions near oxygen vacancies (
Laguta et al. (Fri,) studied this question.