配合物形成的三维超分子体系—[Ni(C_6H_4O_2N)_2(H_2O)_4]的水热法合成、晶体结构及热分析

采用水热法用Ni(NO3)26H2O和异烟酸制备出了一种新的由配合物形成的三维超分子体系—Ni(C6H4O2N)2(H2O)4],并通过X射线衍射对其晶体结构进行了测定。 该晶体属三斜晶系,空间群为Pī, 所得晶胞参数为: a = 6.9228(4), b = 9.6664(19),c = 6.322(1) , a = 96.86(3), b = 113.33(3), g = 110.35(3)°, V = 347.6(1) 3, Z = 1, Mr = 374.98, Dc = 1.791 g/cm3, F(000) = 194, m = 1.443 mm-1。用1362个可观察的 (I > 2s(I))衍射点,修正123个结构参数, 最终偏离因子R = 0.0444,wR = 0.1271。在组成该化合物的基本结构单元Ni(C6H4O2N)2(H2O)4]中,Ni处于1个稍微拉长的八面体的中心; 各个结构单元之间通过氢键OH…O相互连接,形成了无限伸展的具有层状结构的三维超分子体系。 另外,从差热及热重曲线可以看出,该化合物加热到154 ℃时开始分解, 首先失去4个H2O,再失去2个异烟酸根,最后残余物为NiO。

Hydrothermal Synthesis, Crystal Structure and Thermal Analysis of a 3-D Supramolecular Structure [Ni(C6H4O2N)2(H2O)4] Formed by Coordination Compounds

A supramolecular compound Ni(C6H4O2N)2(H2O)4] was synthesized by the reaction of Ni(NO3)26H2O and isonicotinic acid through hydrothermal method. The results of single-crystal X-ray diffraction revealed that it consists of Ni(C6H4O2N)2(H2O)4] units in which the Ni(Ⅱ) ion is located in a slightly distorted octahedral center. Each unit is connected by the OH…O hydrogen bonds to form a three-dimensional layered structure. TG-DTA studies indicate that this supramolecular compound is thermally stable below 154 ℃.