Abstract Two novel coordination polymers {(MV)[M3(dca)8]}n (MV2+ = methylviologen dication, dca = dicyanamide anion, M = Co (1) and Ni (2)) have been synthesized by the reactions of methylviologen dichloride and sodium dicyanamide with cobalt(II) or nickel(II) ions. Their structures have been determined by single-crystal X-ray diffraction analysis and further characterized by elemental analysis, infrared spectra, and thermogravimetric analytical techniques. Compounds 1 and 2 are isomers, and crystallize in a centrosymmetric P21/n space group. In the structures of 1 and 2, the metal ions are attached through the µ1,3,5- dicyanamide groups generating a 2D sheet in bc plane. Furthermore, the neighbouring sheets are supported by the strut µ1,5-dca ligands into a 3D framework with open channels occupied by MV2+ cations. Magnetic studies indicate that, compound 1 exhibits antiferrimagnetic coupling between cobalt(II) ions, whereas ferromagnetic interaction was occurred between nickel(II) ions in compound 2.

中文翻译：

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磁性主体中甲基紫精二甲基化的无机-有机杂化材料：合成、晶体结构和磁性

摘要 通过二氯化甲基紫精的反应合成了两种新型配位聚合物 {(MV)[M3(dca)8]}n（MV2+ = 甲基紫精二阳离子，dca = 双氰胺阴离子，M = Co (1) 和 Ni (2)）和双氰胺钠与钴 (II) 或镍 (II) 离子。它们的结构已通过单晶 X 射线衍射分析确定，并通过元素分析、红外光谱和热重分析技术进一步表征。化合物 1 和 2 是异构体，在中心对称 P21/n 空间群中结晶。在 1 和 2 的结构中，金属离子通过 μ1,3,5- 双氰胺基团连接，在 bc 平面上生成二维薄片。此外，相邻的片材由支杆 µ1,5-dca 配体支撑成 3D 框架，其中开放通道被 MV2+ 阳离子占据。磁性研究表明，