【摘要】 通过水热方法合成了2个由多铌酸盐和过渡金属配合物形成的有机-无机杂化配合物[Cu(TETA)]4[VNb12(VO)4O40][OH]·10H2O(1)和[Cu(TETA)]4[VNb12(VO)6O40][OH]5·5H2O(2)(TETA=三亚乙基四胺).化合物1和2的多阴离子分别是由4个{VO5}帽和6个{VO5}帽加盖在Keggin型多铌酸盐的方形缺口上形成的,它们通过多酸阴离子中Nb—O t(O t=端氧)与[Cu(TETA)]2+配合物的金属中心配位构筑形成三维结构.价键计算结果表明,Keggin中心的钒为+5价,帽位的钒为+4价,X射线光电子能谱分析(XPS)结果也证实了这一结论.通过单晶X射线衍射分析、红外光谱(IR)、粉末X射线衍射(PXRD)、热重(TG)分析和元素分析对这2个化合物的结构和性质进行了表征.更多还原

【Abstract】 Two organic-inorganic hybrid compounds constructed from polyoxoniobates and transition metal coordination complexes,[Cu(TETA) ] 4 [VNb 12(VO) 4 O 40 ][OH]·10H 2 O(1) and [Cu(TETA) ] 4 · [VNb 12(VO) 6 O 40 ][OH] 5 ·5H 2 O(2)(TETA = triethylenetetramine),have been hydrothermally synthesized and characterized by single-crystal X-ray diffraction analyses,IR spectra,X-ray photoelectron spectrum(XPS),powder X-ray diffraction(PXRD),thermogravimetric analysis(TGA) and elemental analyses.Compound 1 is a 3D tetra-capped vanadoniobates and compound 2 is a 3D hexa-capped vanadoniobates which are constructed from heteropolyoxometalates and [Cu(TETA) ]2 +fragments.The result of bond valence sum calculations indicates that the vanadium centers of VO 4 tetrahedral in{ VNb 12 } Keggin unit in compounds 1 and 2 are in oxidation state + Ⅴ whereas the remaining vanadium centers are in oxidation state + Ⅳ.This is in line with the analysis of X-ray photoelectron spectrum.更多还原