摘要
用缺陷化学方法讨论了Nd3+、Th4+、Sb5+掺杂PbWO4(PWO)中可能存在的杂质缺陷模型,用GULP软件计算了不同杂质缺陷的生成能.计算结果表明,Nd3+和Th4+将占据PWO晶体中VP2b-周围的Pb位,对VP2b-的电荷补偿抑制了PWO晶体中420 nm吸收带.Sb5+在高浓度掺杂时将占据PWO晶体中V2O+周围的W位,并由于占据W位所呈现的一价负电性补偿V2O+的正电性,使孤立的铅空位增多,引起350 nm吸收的减弱和420 nm吸收的增强.
The positions of the impurity ions of Nd^3＋ ,Th^4＋ ,Sb^5＋ in PbWO4（PWO） crystal are simulated by computer technology. The corresponding defect clusters energy is calculated. The defect chemistry and the formation of the defect clusters are discussed. The mechanism of the doping effects of Nd^3＋, Th^4＋, Sb^5＋ are studied. The calculation results show that the Nd^3＋ and Th^4＋ would occupy the Pb sites near VPb^2-, and restrict the 420 nm absorption band by compensating the electronegative charges of VPb^2- . When the PWO is doped with high concentration, the Sb^5 ＋ would occupy the W sites near VO^2＋ , make the VPb^2- capture two holes more easily to form the colour center of 420 nm absorption. The conclusions are detailedly discussed.
出处
《上海理工大学学报》
EI
CAS
北大核心
2007年第2期117-120,共4页
Journal of University of Shanghai For Science and Technology
关键词
PBWO4晶体
掺杂机制
缺陷簇模型
模拟计算
PbWO4 Crystal
mechanism of doping
models of defect dusters
simulation calculation
