镧系1：10系列钼钒杂多配合物的合成与性质

Synthesis and Properties of 10-heteropolymolybdovanadate Complexes of Lanthanide Elements

报道用一步酸化法制得了四种未见报道的１：１０系列镧系钼钒杂多配合物Ｋ７Ｈ８ＬｎＭｏ４Ｖ６Ｏ（３６）·ｘＨ２Ｏ（Ｌｎ＝Ｌａ、Ｃｅ、Ｐｒ、Ｎｄ）。根据元素分析、红外光谱、紫外光谱、Ｘ射线粉末衍射及差热－热重分析结果讨论了它们的结构及性质。

he four new title heteropoly complexes with a general formula K_7H_8LnMo_4V_6O_(36)·xH_2O (Ln = La, Ce, Pr, Nd; x=23￣25) have been synthesized by the one-step acidification for the first time. The complexes are very soluble in water and stable at pH= 4. 2￣8. 9. The fact that infrared and Raman spectra of the heteropoly complexes recorded all have same vibrational frequencies indicates that they probably have similar basic skeleton structure. The electronic spectra of them are very similar within 190￣400 nm, the absorption bands do not change with kind of lanthanide elements. There are two absorption bands in the region, the absorption band at 206￣207 nm is due to O_d→M electron-charge transition, the other band at 232￣ 236 nm is due to O_(b,c)→M transition ,these also show that they have the same electronic structure. The hypersensitive absorption bands (Pr￣(3+), Nd￣(3+)) in the 450￣900 nm region of the complexes shows a red shift as compared with the aqueous ions. This shows that Ln￣(3+) ions are in the inner sphere of the complexes and there are covalent bonds between Ln￣(3+) and the ligands of molybdenum and vanadium. Thermal stability studies onthe heteropoly complexes were conducted by thermogravimetric(TG) analysis and differential thermal analysis. The decomposition temperature of the complexes have been determined to be 100￣150℃ by IR srectra and X-ray powder diffraction at different temperatures.