LaSrAlO4中Cu2+的自旋哈密顿参量的理论分析

根据晶体场理论，利用3d9离子在四角对称(伸长八面体)中自旋哈密顿参量g因子的四阶微扰公式以及超精细结构常数A因子的三阶微扰公式，对掺Cu2+的LaSrAlO4晶体的自旋哈密顿参量作出了理论分析。其中的四角晶场参量Ds、Dt由重叠模型和杂质中心的局部结构计算，A因子公式中的芯区极化常数κ≈0.286。所得到的计算值与实验符合较好，并从理论上确定了A//为负值。

On the basis of the perturbation formulae of the g-factors (fourth-order) and the hyperfine structure constants (third-order) for a 3d9 ion in tetragonal symmetry (elongated octahedra), the spin Hamiltonian parameters for the Cu2+-doped LaSrAlO4 crystal are theoretically investigated. In the calculations, the tetragonal field parameters Ds and Dt are determined from the superposition model and the local structure of the impurity center; and the core polarization constant κ ≈0.286. Based on the studies, it is found that the calculated values show good agreement with the experimental data. In addition, the negative sign of A// is also determined theoretically.