采用基于密度泛函理论的相对论性离散变分和嵌入团簇方法计算了掺镧PbWO4晶体中相对缺陷的电子态密度分布,并讨论了相关缺陷的电荷补偿机制.发现VPb是掺镧钨酸铅晶体中主要的电荷补偿方式.缺陷态LaPb+VPb的态密度分布以及其激发能的计算结果表明:掺镧晶体不会引起420nm和350nm的吸收,改善了PbWO4晶体中的两个本征吸收带.掺杂后晶体中O2p→W5d的跃迁能量为3.98eV.
参考文献
| [1] | Kobayshi M;Usuki Y et al.Scintillation Characterisitics of PbWO4 Single Crystals at Room Temperature[J].Nuclear Instruments and Methods in Physics Research,1993,A333:429-435. |
| [2] | Kobayshi M;Usuki Y et al.Significant Improvement of PbWO4 Scintillating Crystals by Doping with Trivalent Ions[J].Nuclear Instruments and Methods in Physics Research,1999,A434:412-423. |
| [3] | Kobayashi M.;Ishii M.;Yazawa T.;Hara K.;Tanaka M.;Nikl M. Baccaro S.;Cecilia A.;Diemoz M.;Usuki Y. .Improvement in radiation hardness of PbWO4 scintillating crystals by La-doping[J].Nuclear Instruments and Methods in Physics Research, Section A. Accelerators, Spectrometers, Detectors and Associated Equipment,1998(1):149-156. |
| [4] | Baccaro S et al.Influence of La3+ Doping on Radiation Hardness and Thermoluminescence Characteristics of PbWO4[J].Physica Status Solidi,1997,A160:5. |
| [5] | Kobayashi M et al.Improvement in Transmittance and Decay Time of PbWO4 Scintillating Ccrystals by La-doping[J].Nuclear Instruments and Methods in Physics Research,1998,A399:261. |
| [6] | 汤学峰 .无机闪烁晶体的缺陷及掺杂效应研究[D].上海:同济大学,1999. |
| [7] | Nikl M;Bohacek P;Nitsch K;Mihokova E;Martini M;Vedda A;Croci S;Pazzi GP;Fabeni P;Baccaro S .Decay kinetics and thermoluminescence of PbWO4 : La3+[J].Applied physics letters,1997(26):3755-3757. |
| [8] | Zhu R Y et al.Decay Kinetics and Thermoluminessence of PbWO4:[J].La3+ J Appl phys,1997,82(01):5758-5762. |
| [9] | ELLIS D E;Guo J .Electronic Density Functional Theory of Molecules.Clusters[Z].Solids,Kluwer,Dordrecht,1995. |
| [10] | 徐光宪.量子化学基础理论和从头计算法[M].北京:科学出版社,1999:1075. |
| [11] | 韩宝国.La：PbWO4晶体中La3+离子的分布及其对晶体辐照硬度的影响[J].人工晶体学报,1998(03):213. |
| [12] | 张明荣,胡关钦,李培俊,徐力,殷之文.La在La：PWO闪烁晶体中的作用机制探讨[J].发光学报,1997(04):320-322. |
| [13] | 姚明珍,顾牧,梁玲,段勇,马晓辉.PbWO4晶体空位型缺陷电子结构的研究[J].物理学报,2002(01):125-128. |
| [14] | 祁金林 .PbWO4晶体发光和辐照损伤机理的研究[D].上海:同济大学,1998. |
上一张
下一张
上一张
下一张
计量
- 下载量()
- 访问量()
文章评分
- 您的评分：
-
10%
-
20%
-
30%
-
40%
-
50%