Syntheses, structures and magnetic properties of three-dimensional co-ordination polymers constructed by dimer subunits
作者:Bai-Wang Sun、Song Gao、Bao-Qing Ma、De-Zhong Niu、Zhe-Ming Wang
DOI:10.1039/b005612j
日期:——
The crystal structures and magnetic properties of compounds [MII(apo)(N(CN)2)2], where M = Co (1), Ni (2) or Mn (3), apo = 2-aminopyridine N-oxide, have been determined. The structural analyses revealed that they are isomorphous, and all belong to monoclinic space group P21/n. The metal(II) ions display distorted octahedral co-ordination, with four terminal N atoms of different [N(CN)2]− ligands and two O atoms of different apo ligands. Two ions are bridged by two μ-O atoms to form a dimer subunit. Those dimers are further linked to each other by [N(CN)2]− resulting in a three-dimensional structure. The magnetic properties of the compounds were investigated in the temperature range 2–300 K for 1 and 2 and 4–300 K for 3. The values for the intradimer spin coupling constant J were estimated to be −17.8, −40, −1.3 cm−1 for 1–3, respectively, indicative of antiferromagnetic interaction.
化合物 [MII(apo)(N(CN)2)2] 的晶体结构和磁性,其中 M = Co (1)、Ni (2) 或 Mn (3),apo = 2-氨基吡啶 N-氧化物,已确定。结构分析表明它们是同晶的,均属于单斜空间群P21/n。金属(II)离子显示出扭曲的八面体配位,具有不同[N(CN)2]−配体的四个末端N原子和不同apo配体的两个O原子。两个离子通过两个 μ-O 原子桥接形成二聚体亚基。这些二聚体通过 [N(CN)2]− 进一步相互连接,形成三维结构。在 1 和 2 的温度范围 2–300 K 以及 3 的 4–300 K 温度范围内研究了化合物的磁性。内二聚体自旋耦合常数 J 的值估计为 -17.8、-40、-1.3 cm -1 分别代表 1-3,表示反铁磁相互作用。