Theoretical Study of Spin-State and Redox Multistability in an Iron [2x2] Grid Complex
Theoretical Study of Spin-State and Redox Multistability in an Iron [2x2] Grid Complex
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DOI：
10.1002/ejic.201201074
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发表时间：
2013-02-01
影响因子：
2.3
通讯作者：
Zueva, Ekaterina M.
中科院分区：
文献类型：
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作者：
Borshch, Serguei A.;Zueva, Ekaterina M.
我们使用量子化学（DFT）计算来阐明铁[2x2]分子网格与吡唑为基础的桥接配体显示自旋态和氧化态多稳定性的自旋交叉途径的起源。该复合物的特点是能量和结构在不同的可用自旋和氧化态。特别注意的是每个铁中心上的任何邻居的自旋跃迁或氧化引起的结构畸变的分析。配位多面体的演化是通过使用连续的形状措施监测。结果表明，不同中心上的自旋跃迁的连续性取决于诱导的畸变是否接近或移动的协调核心几何远离一个更规则的低自旋几何。这些效应以及整体网格几何形状由配体中的空间应变驱动。计算了不同格点态的穆斯堡尔谱参数和交换耦合常数。
We use quantum-chemical (DFT) calculations to elucidate the origin of spin-crossover pathways in the iron [2x2] molecular grid with pyrazole-based bridging ligands displaying spin-state and oxidation-state multistability. The complex is characterized energetically and structurally in different available spin and oxidation states. Special attention is paid to the analysis of the structural distortion induced on each iron center by spin transition on any of its neighbors or by oxidation. The evolution of coordination polyhedra is monitored by using continuous shape measures. It is demonstrated that a succession of spin transitions on different centers depends on whether the induced distortion approaches or moves the coordination core geometry away from a more regular low-spin geometry. These effects, as well as the overall grid geometry, are driven by the steric strain in the ligands. We also calculate the parameters of Mossbauer spectra and exchange coupling constants for different grid states.