一种三维配位聚合物的水热合成和晶体结构

通过水热合成法获得了La2（H20）4（PDC）2（XO）·2H2O，X射线-单晶衍射结果表明，标题化合物属于单斜晶系，空间群为P2（1）／n，晶胞参数为a=0．77512（16）nm，b=0．9975（2）nm，c=1．5142（3）nm，β=98．50（3）°和Z：4。La（Ⅲ）呈现四方反棱柱体的配位模式，分别和2个来自同一个草酸配体的氧原子、4个来自4个PDC配体的氧原子以及2个来自2个配位水分子的氧原子配位。标题化合物的三维结构是通过草酸配体和水分子配体将二维La（PDC）]^＋阳离子层连接而成。该三维网络结构中沿着a-轴形成孔道，标题化合物中的自由水分子占据了这些孔道。该化合物在250℃下保持热稳定。

Hydrothermal Synthesis and Crystal Structure of a 3D Coordination Compound

La2 （ H2 O） 4 （ PDC ） 2 （XO）·2H2 O was hydrothermally synthesized, and single crystal X - ray diffraction revealed that the title compound crystallizes in monoclinic, space group P2（ 1 ）/n with a =0. 77512（16） nm, b =0. 9975 （2） nm, c = 1. 5142（3） nm, β=98.50（3）° and Z =4. The coordination mode of La（Ⅲ） can be described as a distorted aquare antiprism, which was completed by two oxygen atoms from one oxalate, four oxygen atoms from four different PDC ligands, and two oxygen atoms from two water molecules. The three - dimensional framework of the title compound was composed of 2 -D layers of La（PDC）]^＋ linked by oxalate ligands and water ligands. The result of 3 -D structure showed open channels along a-axis, which were occupied by free water molecules.