A Series of Heterometallic Three-Dimensional Frameworks Constructed from Imidazole鈥揇icarboxylate: Structures, Luminescence, and Magnetic Properties

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• 作者：Xun Feng ; Lu-Fang Ma ; Lang Liu ; Li-Ya Wang ; Hong-Liang Song ; Shi-Yu Xie
• 刊名：Crystal Growth & Design
• 出版年：2013
• 出版时间：October 2, 2013
• 年：2013
• 卷：13
• 期：10
• 页码：4469-4479
• 全文大小：629K
• 年卷期：v.13,no.10(October 2, 2013)
• ISSN：1528-7505

文摘

The combination of lanthanide and zinc nitrates reaction with a rigid 1-H-2-methyl-4,5-imidazole-dicarboxylic acid yields a new zinc complex of Zn(Hmimda)₂路2H₂O (1) and a family of heteronuclear polymers, namely, {[Ln₂Zn₂(渭₃-Hmimda)₂ (渭₃-mimda)₂路4H₂O]路mH₂O}_n, Ln = Sm, m = 2 (2), Ln = Eu, m = 3 (3), Ln = Gd, m = 2 (4), Ln = Tb, m = 3 (5), Ln = Dy, m = 3 (6) (H₃mimda = 1H-2-methyl-4,5-imidazole-dicarboxylic acid). Structural analysis shows that complexes 2鈥?b>6 are isostructural and all crystallize in the monoclinic system, except for a slight disparity for 2. They have an extended nonporous structure constructed from tetraheteronuclear edifices with new framework topology, in which the Ln(III)鈥揨n square tetranuclear complexes act as the second building unit, which are further interconnected by the Hmimda to afford a two-dimensional corrugated layer. Both compounds 5 and 6 exhibit characteristic fluorescence in the visible region. The variable temperature magnetic investigations indicate that the magnetic interactions are mainly ascribed to depopulation of the Stark levels or possible antiferromagnetic couplings. The Dy(III)鈥揨n(II) compound exhibits possible ferromagnetic couplings and slow magnetic relaxation behavior of a single-molecule magnet nature.