新型五硼酸盐的熔盐合成及结构表征

Plasma-nitriding synthesis method and structure characterization of a pentaborate

通过低温熔盐法合成了一种新型五硼酸盐RbB5O7(OH)2.H2O,单晶X射线衍射结果证明该化合物属单斜晶系,P2/c空间群,a=0.764 0(2)nm,b=0.901 9(3)nm,c=1.083 3(3)nm,β=103.681(5)°,V=0.725 2(4)nm3,Z=2.结构中BO3,BO2(OH)2,BO4基团形成的[B5O7(OH)2]-之字链结构与RbO+相连构成九面体-四面体空间骨架,水分子靠近之字链结构通道内侧,起到稳定骨架的作用.同时通过X粉晶衍射、红外光谱、热重等对化合物进行了表征.

A pentaborate compound RbB5O7（OH）2·H20is prepared by cryogenic molten-salt method synthe- sis and characterized by X-ray single crystal diffraction. The title compound to monoclinic belongs systerm, space group P2/c, α=0.7640（2）nm,b=0.9019（3）nm,c=1.0833（3）nm,β=103.681（5）°,V=0.7252（4）nm^3,Z=2. The crystal structure of the compound contains infinite zigzag chain structure 1∞ [B5O7（OH）2],built of comer sharing BO3, BO2 （OH）2 and BO4 group. The chain things are connected via Rb＋ coordination octabedra. The central channel is flied by a helix made of water molecules. At tlae same time the title compound is charactered by XRD,IR,TG.