In this work, the electron paramagnetic resonance (EPR) parameters (g-factors and A-constants) of the tetragonal VO²⁺ centers in LiHSO₄ single crystals are theoretically investigated by the high-order perturbation formulae for these parameters based on two-spin–orbit-parameter model. Since the spin–orbit coupling coefficient of the ligand O²⁻ is close to that of the central ion V⁴⁺ for the present system with strong covalence, the contributions to the EPR parameters from the ligand p- and s-orbitals as well as the spin–orbit coupling coefficient of the O²⁻ ligand should be considered. The requirements of the crystal-field parameters are determined from the optical spectrum. The calculated results show good agreement with the experimental values. The signs of A-constants are ascertained in the discussion.

在这项工作中，理论上通过高扰动公式针对LiHSO ₄单晶中的四方VO ²⁺中心的电子顺磁共振（EPR）参数（g因子和A常数）研究了这些参数，基于两个自旋轨道参数模型。对于本系统，由于配体O ²⁻的自旋轨道耦合系数接近中心离子V ⁴⁺的自旋轨道耦合系数，因此配体p和s轨道对EPR参数的贡献以及O ²⁻的自旋轨道耦合系数应考虑配体。晶体场参数的要求由光谱确定。计算结果与实验值吻合良好。在讨论中确定了A常数的迹象。