CsNiCl_3晶体的光谱精细结构、零场分裂参量及Jahn-Teller效应  

Spectral hyper-fine structure and zero-field splitting parameters with Jahn-Teller effect of CsNiCl_3 crystal+

作　　者：殷春浩[1] 焦杨[1] 张雷[1] 宋宁[1] 茹瑞鹏[1] 杨柳[1] 

机构地区：[1]中国矿业大学理学院,徐州221008

出　　处：《物理学报》2006年第11期6047-6054,共8页Acta Physica Sinica

基　　金：国家教育部留学回国人员实验室建设科研基金(批准号:2003.18);中国矿业大学优秀创新团队基金(批准号:2004ZCX012)资助的课题.~~

摘　　要：应用不可约张量理论构造了三角对称晶场中3d2/3d8态离子的45阶可完全对角化的微扰哈密顿矩阵,研究了CsNiCl3晶体的光谱精细结构、晶体结构、零场分裂参量、Jahn_Telller效应以及自旋单重态对Ni2+离子基态能级的影响,理论与实验相符合.在此基础上,进一步研究了以前工作中被忽略的自旋_自旋耦合作用和Trees修正对CsNiCl3晶体的光谱精细结构和零场分裂参量的影响,发现有四种机理会影响零场分裂参量:1)自旋-轨道耦合机理,2)自旋_自旋耦合机理;3)自旋_轨道与自旋_自旋联合耦合机理;4)自旋_轨道与Trees修正联合耦合机理,其中自旋_轨道耦合机理是最主要的,其他三种机理也是不可忽略的.The complete diagonalized Hamiitonian matrixes of 3d^2/3d^8 ion configuration with trigonal symmetry have been established by irreducible representation method. The spectral hyper-fine structure and the constants of crystal structure and zero-field splitting parameters of CsNiCl3 crystal, as well as the Jahn-Teller effect and the influence of the spin singlet on the ground levels of Ni^2 ＋ ion have been studied. The results agree with the experimental facts. Besides, taking into account the influence of the spin-spin （SS） coupling interactions and the Trees correction which were neglected in previous publications, we find that the zero-field splitting parameters arise from four mechanisms, namely： （1） Spin-orbit coupling mechanism; （2） Spin-spin coupling mechanism; （3） Spin-orbit and spin-spin combined coupling mechanism; （4） Spin-orbit and Trees correction combined coupling mechanism. The spin-orbit coupling mechanism is the most important one and the other three mechanisms can not be neglected.

关 键 词：基态能级 精细结构 零场分裂 自旋-自旋耦合 

分 类 号：O482[理学—固体物理]