Electron paramagnetic resonance (EPR) and optical spectra are the effective tools in studying the optical and magnetic properties of crystals and complexes doped with rare-earth ions.

• 电子顺磁共振(EPR)谱及光谱是研究掺过渡和稀土金属离子晶体及络合物的光学和磁学等性质并揭示其微观结构的有力工具。 EPR谱常用自旋哈密顿参量描述。