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以α-Na7PW11O39·nH2O,LaCl3·7H2O和(CH3)4NCl为原料,利用常规水溶液方法合成了2:2型二聚的单缺位Keggin结构稀土衍生物[(CH3)4N]4[PW11O39H2La(H2O)4]2·3H2O(1).X射线单晶衍射结果表明,该晶体属三斜晶系,P-1空间群,晶胞参数:a=1.35383(10)nm,b=1.60687(12)nm,c=1.86958(13)nm,α=65.9630(10)°,β=83.1650(10)°,γ=83.6780(10)°,Z=1,R1=0.0589,wR2=0.1447.二聚阴离子{[(α-PW11O39H2)La(H2O)4]2}4-由2个[α-PW11O39]7-缺位阴离子通过2个[La(H2O)4]3+配离子连接形成,La3+离子占据[α-PW11O39]7-阴离子的缺位位置,采用九配位单加冠四方反棱柱构型,相邻的2个单取代阴离子[α-PW11LaO39]4-通过2个La–Ot–W桥连成二聚物.热重分析结果表明,化合物1在25～600℃范围内表现为两步失重;循环伏安行为表明,化合物1阴离子在pH4.3的水溶液中存在两步可逆的单电子还原过程.
A novel 2: 2 dimeric single-vacancy Keggin structure [(CH3) 4N] 4 [PW11O39H2La (H2O) was synthesized from α-Na7PW11O39 · nH2O, LaCl3 · 7H2O and (CH3) 4NCl using conventional aqueous methods. ) 4] 2 · 3H2O (1). The results of X-ray single crystal diffraction show that the crystal belongs to the triclinic system with P-1 space group and unit cell parameters of a = 1.35383 (10) nm and b = 1.60687 nm = 1.86958 (13) nm, α = 65.9630 (10) °, β = 83.1650 (10) °, γ = 83.6780 (10) °, Z = 1, R1 = 0.0589, wR2 = 0.1447. [(α-PW11O39H2) La (H2O) 4] 2} 4- is formed by the connection of two [La (H2O) 4] 3+ ions through two [a-PW11O39] 7- vacancy anions, α-PW11O39] 7-anions in the absence of position, the use of nine coordination single crown anti-prism configuration, the two adjacent monosubstituted anion [α-PW11LaO39] 4- by two La-Ot-W bridge into Dimer.The results of thermogravimetric analysis showed that compound 1 showed two-step weight loss in the range of 25-600 ℃. The cyclic voltammetry showed that there was two-step reversible one-electron reduction of compound 1 anion in aqueous solution of pH 4.3 .