Theoretical investigation for the EPR g factors and the local structure for the two tetragonal Ni3+ centers in ACoO2 (A = H, Li)
Theoretical investigation for the EPR g factors and the local structure for the two tetragonal Ni3+ centers in ACoO2 (A = H, Li)
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DOI：
10.1016/j.jallcom.2013.08.185
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发表时间：
2014-01
影响因子：
6.2
通讯作者：
Huaming Zhang;W. Xiao;X. Wan
中科院分区：
文献类型：
--
作者：
Huaming Zhang;W. Xiao;X. Wan
本文从电子顺磁共振因子的微扰公式出发，理论研究了HCoO_2和LiCoO_2中Ni3+四方中心的电子顺磁共振因子和局域结构。在这些公式中，相关的分子轨道系数是由团簇方法统一定量确定的。根据计算，由于Jahn-Teller效应，Ni3+周围的配体八面体在HCoO2(和LiCoO2)中的四方Ni3+中心沿[0，0，1](ORC4)轴的相对伸长为2.57%(和1.6%)。根据上述Jahn-Teller伸长率计算的因子与观测值吻合较好。
The electron paramagnetic resonancegfactors and the local structure for the tetragonal Ni3+centers in HCoO2and LiCoO2are theoretically studied from the perturbation formulas of thegfactors for a 3d7ion with low spin (S= 1/2) in tetragonally elongated octahedra. In these formulas, the related molecular orbital coefficients are quantitatively determined from the cluster approach in a uniform way. According to the calculations, the ligand octahedra around Ni3+are suggested to suffer relative elongation 2.57% (and 1.6%) along the [0 0 1] (orC4)axis for the tetragonal Ni3+centers in HCoO2(and LiCoO2), due to the Jahn–Teller effect. The calculatedgfactors based on the above Jahn–Teller elongations are in good agreement with the observed values.