单晶电子顺磁共振研究中零场分裂张量主轴的确定

用电子顺磁共振二维旋转测角器确定量子化轴即零场分裂张量的一个主轴,根据矢量的正交关系计算与量子化轴垂直的主轴平面上的取向二维角组、以便按照计算的二维角组测量电子顺磁共振谱,确认零场分裂张量的另外两个主轴,同时确定了主轴座标系(X,Y,Z)相对实验座标系(x,y,z)的Euler角。以渗Cr³⁺的Na₃(AlMo₆O₂₄H₆)·8H₂O单晶的电子顺磁共振测量作为上述方法的一个应用例子。 关键词：

DETERMINATION OF PRINCIPAL AXES OF ZERO-FIELD SPLITTING TENSOR BY SINGLE CRYSTAL EPR STUDY

The quantization axis, which is one of the principal axes of the zero-field splitting tensor, can be determined by means of the EPR two-circle goniometer. The sets of two dimensional angles of the orientations on the principal plane perpendicular to the quantization axis have been calculated according to the orthogonality of vectors. One can measure the EPR spectrum of different orientations based on the calculated sets of two dimensional angles, and specify the two other principal axes. In this way, one can determine the Eulerian angles by which the laboratory axis system (x, y, z) are related to the principal axis system (X, Y. Z). The procedure has been applied to the measurement of X band EPR data for Cr³⁺-doped Na₃(AlMo₆O₂₄H₆)·8H₂O single crystal as an illustrative example.