γ-[SiW_(10)O_(36)]^(8-)夹心型稀土元素单取代多酸化合物的合成与表征

Synthesis and Characterization of Sandwich Rare Earth Metal Mono-substituted Polyoxometalates with γ-[SiW_(10)O_(36)]~ (8-) as Ligand

利用缺位填充法合成了 1 2个 γ-[Si W1 0 O36 ]8-夹心型稀土元素单取代多酸化合物 K1 3[Ln( Si W1 0 O36 ) 2 ]·n H2 O( Ln=La3+ ,Ce3+ ,Pr3+ ,Nd3+ ,Sm3+ ,Eu3+ ,Gd3+ ,Tb3+ ,Dy3+ ,Ho3+ ,Er3+ ,Yb3+ ) .通过元素分析确定其组成 ,由红外光谱、紫外 -可见吸收光谱、循环伏安及室温磁化率测定结果确认稀土离子与γ-[Si W1 0 O36 ]8- 相配位 ;1 83W NMR及荧光光谱结果则表明 ,稀土离子处于 2个 γ-[Si W1 0 O36 ]8- 构成的八配位环境中 ,标题化合物具有夹心型 D2

Twelve rare earth metal mono-substituted polyoxometalates, K 13 [Ln(γ-SiW 10O 36) 2]·nH 2O(Ln=La 3+, Ce 3+, Pr 3+, Nd 3+, Sm 3+, Eu 3+, Gd 3+, Tb 3+, Dy 3+, Ho 3+, Er 3+, Yb 3+), were synthesized by vacant sites-filling method by using γ- [SiW 10O 36] 8- as the ligand. The compounds were characterized by elemental analysis, UV-Vis absorption spectra, IR spectra, CV, paramagnetic measurement, fluorescence spectra and 183W NMR. These results indicate that the rare earth metal ion is coordinated with eight terminal oxygen atoms of two γ- [SiW 10O 36] 8- ligands with D 2d symmetry and the title compounds have 1∶2 sandwich structure.