A simple semi-classical model of magnetization dynamics based on Landau-Lifshits equation of motion with anisotropic effective g-tensor and anisotropic spin relaxation is proposed and applied to the case of electron paramagnetic resonance (EPR). In the Faraday geometry, the model predicts polarization effect consisting in strong dependence of the EPR line shape and magnitude on orientation of vector h of oscillating magnetization with respect to the crystal structure, so that EPR may be suppressed for some directions of h. The EPR with anisotropic parameters possesses specific magnetic oscillations, which are different from standard circular rotation of the magnetization vector around the direction of external magnetic field. In general case, the trajectory of the magnetization vector end is either elongated quasi-ellipse, the position of the main axis of which depends on the magnitude of the external magnetic field, or magnetic oscillations may acquire almost linear character. The model is successfully applied for the quantitative accounting of the polarization effect for EPR mode observed in CuGeO₃ doped with 2% of Co impurity, which remained unexplained for more than 15 years.

提出了一种基于具有各向异性有效g张量和各向异性自旋弛豫的Landau-Lifshits运动方程的简单半经典磁化动力学模型，并将其应用于电子顺磁共振（EPR）的情况。在法拉第几何中，该模型预测极化效应包括 EPR 线形状和幅度对振荡磁化矢量h相对于晶体结构的方向的强烈依赖性，因此 EPR 可能在h的某些方向上被抑制. 具有各向异性参数的EPR具有特定的磁振荡，这不同于磁化矢量围绕外部磁场方向的标准圆周旋转。在一般情况下，磁化矢量端的轨迹要么是拉长的准椭圆，其主轴的位置取决于外部磁场的大小，要么磁振荡可能获得几乎线性的特征。该模型成功地应用于在掺杂 2% Co 杂质的 CuGeO ₃中观察到的 EPR 模式的极化效应的定量计算，这在超过 15 年的时间里仍未得到解释。