Theoretical investigation on the EPR parameters for VO2+ doped ZnO–CdS nanocomposites
Theoretical investigation on the EPR parameters for VO2+ doped ZnO–CdS nanocomposites
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DOI：
10.1140/epjd/e2019-100312-4
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发表时间：
2020-01
期刊：
影响因子：
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通讯作者：
Quansong Zhu;Ya-Dong Li;Baojin Chen;Huaming Zhang
中科院分区：
文献类型：
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作者：
Quansong Zhu;Ya-Dong Li;Baojin Chen;Huaming Zhang
本文研究了三个光学吸收带和电子顺磁共振（EPR）参数g因子（g||，g_∞）和超精细结构常数（A||利用基于团簇方法的3d 1离子在四面体压缩八面体下EPR参量的微扰公式，对VO 2+掺杂ZnO-CdS纳米复合材料的EPR参量进行了理论研究.在计算公式中，VO 2+掺杂的局域结构与EPR参量之间的关系由晶体场参量通过四重态畸变（表征为相对四重态压缩比τ）建立，并考虑了配体轨道和自旋-轨道耦合作用通过共价效应对EPR参量的贡献。研究发现，由于Jahn-Teller效应，V4+掺杂在z轴方向上具有沿着的相对压缩比τ（约2.1%）.计算结果与实验数据吻合较好。讨论了该模型的合理性。图形摘要
AbstractThe three optical absorption bands and electron paramagnetic resonance (EPR) parametersgfactors (g||,g⊥) and the hyperfine structure constants (A||,A⊥) for VO2+doped in the ZnO–CdS nanocomposites are theoretically investigated by using the perturbation formulas of these EPR parameters for a 3d1ion under tetragonally compressed octahedral based on the cluster approach. In the calculation formulas, the relationships between local structure of the VO2+dopants and the EPR parameters are established from the crystal-field parameters via the tetragonal distortion (characterized by relative tetragonal compression ratioτ), and the contributions to EPR parameters arising from the ligand orbital and spin-orbit coupling interactions via covalence effect are considered. Based on the studies, the V4+dopants are found to show a relative compression ratioτ(≈ 2.1%) along thez-axis due to Jahn–Teller effect. Calculated results show reasonable agreement with the experimental data. Reasonableness of the proposed model is discussed.Graphical abstract