Modulating Single-Molecule Magnetic Behavior of a Dinuclear Erbium(III) Complex by Solvent Exchange

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• 作者：Jing-Yuan Ge ; Long Cui ; Jing Li ; Fei Yu ; You Song ; Yi-Quan Zhang ; Jing-Lin ZuoMohamedally Kurmoo
• 刊名：Inorganic Chemistry
• 出版年：2017
• 出版时间：January 3, 2017
• 年：2017
• 卷：56
• 期：1
• 页码：336-343
• 全文大小：491K
• ISSN：1520-510X

文摘

[Er₂(thd)₄Pc]·2C₆H₆ (1) (Hthd = 2,2,6,6-tetramethylheptanedione), obtained as green crystals from the reaction of [Er(thd)₃]·2H₂O with lithium phthalocyanine, Li₂Pc, is a stable dinuclear complex with two Er^III centers. Its lattice benzene solvent can be exchanged by soaking the crystals in dichloromethane to give [Er₂(thd)₄Pc]·2CH₂Cl₂ (2). The magnetic susceptibility data suggest different coupling interactions for the two complexes. While 1 exhibits fast relaxation and an estimated energy barrier of E_a = 2.6 cm^–1 under 600 Oe dc field, the single-molecule magnet behavior of 2 is field-induced and the energy barrier is higher at 34.3 cm^–1. Ab initio calculations were performed to understand the nature of the coupling interaction between two Er^III ions bridged by the phthalocyanine and the origin of different magnetic behavior. Importantly, the single-molecule magnetic properties can be reversibly tuned through the exchange of solvent molecules, confirmed by further measurements on the reverse solvated complexes 1-re and 2-re. This subtle control of relaxation by lattice solvents is rarely observed in single-molecule magnets, especially for Er^III-based complexes.