KPb2Cl5晶体中掺杂Er3+和Eu3+离子占据格位倾向性的原子模拟研究

摘要

Atomic-scale simulation technique was employed to investigate the site preferences of Er3+ and Eu3 + when doped into the KPb2Cl5 crystal. Empirical potential parameters were obtained by fitting to the crystal structures of KPb2Cl5, PbCl2, ErCl3 and EuCl3 The intrinsic defects and substitution defects were studied on the basis of fitted potential parameters. According to the calculated solution energies, it was found that Er3+ and Eu3+ ions prefers to occupy the Pb2 site with a vacancy at the nearest-neighbor K site for charge compensation. This conclusion agrees with the results from spectroscopic analysis of KPb2Cl5: Eu3+ and also provides a theoretical support for site-preference assumption of Er3* when doped in the KPb2Cl5 crystal.%本文采用经验势原子方法模拟研究了稀土Er3+和Eu3+离子掺入KPb2Cl5晶体的格位占据情况,其中经验势参数通过拟合KPb2Cl5、PbCl2、ErCl3、EuCl3晶体结构得到.在此基础上,研究了KPb2Cl5晶体的本征缺陷和替代缺陷,而且通过溶解反应能计算发现,掺杂Er3+/Eu3+离子更倾向于占据Pb2格位,并由最近邻的K空位缺陷提供电荷补偿.这一结论与文献报道的KPb2Cl5:Eu3+光谱分析结果一致,为Er3+掺杂KPb2Cl5占据格位实验假设提供理论支持.