A new polyoxometalate based on mono-lacunary Dawson polyoxoanion: molecular structure of [{Nd(H_2O)_3(α2-P_2W_(17)O_(61))}_2]^(14–)  

作　　者：柏 杨冬 王敬平 牛景杨 

机构地区：[1]Institute of Molecular and Crystal Engineering, School of Chemistry and Chemical Engineering, University of Henan

出　　处：《Journal of Rare Earths》2008年第4期478-482,共5页稀土学报（英文版）

基　　金：the Nature Science Foundation of Henan Province (0611011900)

摘　　要：A new polyoxometalate dimer based on lacunary Wells-Dawson anion and lanthanide cation, Na14[{Nd（H2O）3 （α2-PeWt7O61）2]·17H2O, was isolated as a sodium salt under ambient conditions and characterized by IR, TG, and X-ray single crystal structure analysis and electrochemistry. It belonged to the triclinic, space group Pi with a=1.26738 （15） nm, b=1.41464 （17） nm, c=2.3254 （4） nm, α=103.142 （2）°, β = 95.122 （2）°, γ=113.9690 （10）°, V=3.6317 （8）nm^3, Z=2, Dc=4.274 mg/m^3, and μ=27.695 mm^-1. The Nd^3＋ ion was substituted for a [W=O]^4＋ unit in the ＂cap＂ site of the tungsten-oxygen framework of the parent Wells-Dawson ion. The cyclic voltammograms of the title compound exhibited nearly chemically reversible one-step one-electron transfer process and two-step irreversible reduction processes. Thermogravimetric showed a one-step slow weight loss stage in the range of 25-850 ℃.A new polyoxometalate dimer based on lacunary Wells-Dawson anion and lanthanide cation, Na14[{Nd（H2O）3 （α2-PeWt7O61）2]·17H2O, was isolated as a sodium salt under ambient conditions and characterized by IR, TG, and X-ray single crystal structure analysis and electrochemistry. It belonged to the triclinic, space group Pi with a=1.26738 （15） nm, b=1.41464 （17） nm, c=2.3254 （4） nm, α=103.142 （2）°, β = 95.122 （2）°, γ=113.9690 （10）°, V=3.6317 （8）nm^3, Z=2, Dc=4.274 mg/m^3, and μ=27.695 mm^-1. The Nd^3＋ ion was substituted for a [W=O]^4＋ unit in the ＂cap＂ site of the tungsten-oxygen framework of the parent Wells-Dawson ion. The cyclic voltammograms of the title compound exhibited nearly chemically reversible one-step one-electron transfer process and two-step irreversible reduction processes. Thermogravimetric showed a one-step slow weight loss stage in the range of 25-850 ℃.

关 键 词：mono-lacunary polyoxometalate Dawson structure rare earths 

分 类 号：O631.3[理学—高分子化学]