Electrochemical consequences of ligand substitution at heterometal centers in polyoxovanadium clusters: Controlling the redox properties via heterometal coordination number
Electrochemical consequences of ligand substitution at heterometal centers in polyoxovanadium clusters: Controlling the redox properties via heterometal coordination number
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多氧钒簇中异金属中心配体取代的电化学后果：通过异金属配位数控制氧化还原性质
DOI：
10.1002/chem.2019/05624
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发表时间：
2020
期刊：
影响因子：
--
通讯作者：
Matson, E. M.
中科院分区：
文献类型：
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作者：
Meyer, R. L.;Anjass, M. H.*;Petel, B. E.;Brennessel, W. W.;Streb, C.;Matson, E. M.
合理控制多钒酸盐-醇盐簇的电化学性能取决于了解各种合成修饰对这些体系整体氧化还原过程的影响。在这项工作中，研究了异质金属功能化团簇中异质离子上配体取代的电子后果。比较了[V5O6(OCH3)12FeCl]（1‐[V5FeCl]）和[V5O6(OCH3)12Fe]X（2‐[V5Fe]X； X=ClO4, OTf）的氧化还原性能，以评价改变铁中心周围配位环境对团簇电化学性能的影响。氯离子与铁离子的配位导致氧化还原过程中的阳极移位。这些异金属功能化簇的电子结构的理论建模表明，1‐[V5FeCl]和2‐[V5Fe] x2的氧化还原谱的差异是由铁中心周围配体数量的变化引起的（例如，6 -座标与5 -座标）。具体来说，氯离子与第六配位位的结合似乎改变了铁原子与混合价多钒氧酸盐核的离域电子结构之间的轨道相互作用。因此，调节异金属配位环境可以用来调节整个簇的氧化还原性质。
The rational control of the electrochemical properties of polyoxovanadate‐alkoxide clusters is dependent on understanding the influence of various synthetic modifications on the overall redox processes of these systems. In this work, the electronic consequences of ligand substitution at the heteroion in a heterometal‐functionalized cluster was examined. The redox properties of [V5O6(OCH3)12FeCl] (1‐[V5FeCl]) and [V5O6(OCH3)12Fe]X (2‐[V5Fe]X; X=ClO4, OTf) were compared in order to assess the effects of changing the coordination environment around the iron center on the electrochemical properties of the cluster. Coordination of a chloride anion to iron leads to an anodic shift in redox events. Theoretical modelling of the electronic structure of these heterometal‐functionalized clusters reveals that differences in the redox profiles of1‐[V5FeCl]and2‐[V5Fe]Xarise from changes in the number of ligands surrounding the iron center (e.g., 6‐coordinate vs. 5‐coordinate). Specifically, binding of the chloride to the sixth coordination site appears to change the orbital interaction between the iron and the delocalized electronic structure of the mixed‐valent polyoxovanadate core. Tuning the heterometal coordination environment can therefore be used to modulate the redox properties of the whole cluster.