CsCdF3:Cr3+晶格畸变及其Cd2+-空位研究

按照零场分裂（ＺＦＳ）的三阶微扰理论和叠加晶场模型，建立了ＺＦＳ参量Ｄ与ＣｓＣｄＦ３：Ｃｒ＾３＋晶格结构之间的定量关系，同时考虑了晶格畸变和Ｃｄ＾２＋空位对零场分裂参量Ｄ的贡献，计算了ＣｓＣｄＦ３：Ｃｒ＾３＋晶体的零场分裂参量Ｄ，计算结果与实验符合甚好，证明了晶格畸变和Ｃｄ＾２＋空位的存在，同时得到ｒ＾３＋离子的Ｆ＾－离子向中心Ｃｒ＾３＋离子分别移动Ｘ１＝０．００２９１ｎｍ，Ｘ２＝０．００１ｎｍ，

Lattice Distortion and Cd2+ Vacancy for CsCdF3:Cr3+ Crystals

The quantificational relationship between EPR zero-field splitting parameter D and structure parameters of Cr³⁺ vacancy centre in CsCdF₃:Cr³⁺ crystals was established according to the superposition model and third-order perturbation theory. The existence of Cd²⁺ vacancy and the lattice distortion were verified. Meanwhile, F^- ion moving toward the central Cr³⁺ ion by X₁=0.00291nm, X₂=0.001nm, X₃=0.00262nm was obtained. Good agreement between the theoretical results and the experimental values shows that the assumption of the Cd²⁺ vacancy and the lattice distortion is reasonable. Although the main of source of the tetragonal crystal field comes from the Cd²⁺ vacancy caused by the charge compensation, the contribution of the lattice distortion can not be neglected.