A Family of Mixed-Metal Cyanide Cubes with Alternating Octahedral and Tetrahedral Corners Exhibiting a Variety of Magnetic Behaviors Including Single Molecule Magnetism

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• 作者：Eric J. Schelter ; Ferdi Karadas ; Carolina Avendano ; Andrey V. Prosvirin ; Wolfgang Wernsdorfer ; Kim R. Dunbar
• 刊名：Journal of the American Chemical Society
• 出版年：2007
• 出版时间：July 4, 2007
• 年：2007
• 卷：129
• 期：26
• 页码：8139 - 8149
• 全文大小：1582K
• 年卷期：v.129,no.26(July 4, 2007)
• ISSN：1520-5126

文摘

A series of structurally related pseudocubic metal cyanide clusters of Re(II) and 3d metal ions[{MX}₄{Re(triphos)(CN)₃}₄] (M = Mn, Fe, Co, Ni, Zn; X = Cl, I, -OCH₃) have been prepared, and theirmagnetic and electrochemical properties have been probed to evaluate the effect of changing the identityof the 3d metal ion. Electrochemistry of the clusters reveals several rhenium-based oxidation and reductionprocesses, some of which result in cluster fragmentation. The richest electrochemistry was observed forthe iron congener, which exists as the Re(I)/Fe(III) cluster at the resting potential and exhibits six clearone-electron reversible redox couples and two, closely spaced one-electron quasi-reversible processes.The [{Mn^IICl}₄{Re^II(triphos)(CN)₃}₄] complex exhibits single molecule magnetism with a fast tunnelingrelaxation process observed at H = 0 determined by micro-SQUID magnetization measurements. Acomparative evaluation of the magnetic properties across the series reveals that the compounds exhibitantiferromagnetic coupling between the metal ions, except for [{Ni^IICl}₄{Re^II(triphos)(CN)₃}₄] that showsferromagnetic behavior. Despite the large ground-state spin value of [{Ni^IICl}₄{Re^II(triphos)(CN)₃}₄] (S =6), only manganese congeners exhibit SMM behavior to 1.8 K.