Using a combination of experimental methods, the substitution tendencies of Li⁺ and involved charge compensation mechanisms are determined and compared in two important similar scintillators, LuAG:Ce and YAG:Ce. The studies were performed on polycrystalline samples prepared by solid phase reactions as well as in single crystals grown by the vertical Bridgman method. The results show that Li⁺ in LuAG:Ce, Li is localized mainly at Lu³⁺ sites with charge compensation brought about by Ce³⁺ → Ce⁴⁺ conversion and creation of anion vacancies. Surprisingly, unlike LuAG:Ce, Li, no evidence for Li⁺ substitution at Y³⁺ sites and conversion of Ce³⁺ to Ce⁴⁺ has been obtained in YAG:Ce, Li. It suggests that Li⁺ goes mainly to interstitial positions and does not interact with Ce³⁺. From an application point of view, Li⁺ co-doping of YAG:Ce is not efficient to improve the scintillationdecay parameters, however, it is efficient to reduce the amount of anion vacancies in both YAG and YAG:Ce.

中文翻译：

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YAG：Ce和LuAG：Ce闪烁石榴石在Li ⁺共掺杂 方面的不同行为

使用实验方法的组合，确定并比较了两个重要的类似闪烁体LuAG：Ce和YAG：Ce中Li ⁺的取代趋势以及所涉及的电荷补偿机制。对通过固相反应制备的多晶样品以及通过垂直Bridgman方法生长的单晶进行了研究。结果表明，LuAG：Ce中的Li ⁺主要分布在Lu ³⁺处，Ce ³⁺ →Ce ^4+的转化和阴离子空位的产生引起电荷补偿。出人意料的是，与LuAG：Ce，Li不同，没有证据表明在Y ³⁺位发生Li ⁺取代和Ce ³⁺转化。在YAG：Ce，Li中获得了对Ce ^4+的吸附。这表明Li ⁺主要进入间隙位置，并且不与Ce ³⁺相互作用。从应用的角度来看，YAG：Ce的Li ⁺共掺杂不能有效地提高闪烁衰减参数，但是，降低YAG和YAG：Ce中阴离子空位的数量是有效的。