一个新的超大铈锑钨酸盐阴离子Ce~3Sb~4W~2O~8(H~2O)~1~0(SbW~9O~3~3)^1^9^-~4

合成了一超大铈锑钨酸盐[Ce~3Sb~4W~2O~8(H~2O)~1~0(SbW~9O~3~3)~4](NH~4)~1~9.48H~2O,用X射线单晶衍射法及元素分析确定了其结构。其晶胞参数为：a=1.8908(6)nm,b=2.0032(14)nm,c=2.8653(12)nm,α=86.95(6)°,β=75.68(3)°,γ=67.52(5)°,V=9.706(9)nm^3，空间群P1。在杂多阴离子Ce~3Sb~4W~2O~8(H~2O)~1~0(SbW~9O~3~3)^1^9^-~4中，四个β-B-(SbW~9O~3~3)^9^-是通过一个大的中心集团[Ce~3Sb~4W~2O~8(H~2O)~1~0]^1^7^+连接起来的，中心集团中含有两个桥连{WO~2(H~2O)}基，三个Ce(Ⅲ)离子和一个{Sb~4O~4}基团。三个Ce(Ⅲ)离子的配位数均为9，Ce(1)和Ce(3)的配位环境相同，但不同于Ce(2)的配位环境，四个{SbW~9O~3~3}中的三个参与了向Ce(Ⅲ)的配位。两个{SbW~9O~3~3}中的四个氧，三个水分子中的三个氧，{Sb~4O~4}中的一个氧及一个桥连{WO~2(H~2O)}中的一个氧向Ce(1)[或Ce(3)]配位；两个{SbW~9O~3~3}中的四个氧，两个水分子中的两个氧，{Sb~4O~4}中的一个氧及两个桥连{WO~2(H~2O)}中的两个氧向Ce(2)配位。在{Sb~4O~4}中，四个Sb原子的中心构成了一四面体。该离子属C~s点群，Sb(5),Sb(8)和Ce(2)所在的平面是其对称面。

A novel large heteropolyanion Ce~3Sb~4W~2O~8(H~2O)~1~0(SbW~9O~3~3)^1^9^-~4

The heteropolytungstate [Ce~3Sb~4W~2O~8(H~2O)~1~0(SbW~9O~3~3)~4](NH~4)~1~9.48H~2O is prepared by the reaction of Na~2WO~4.2H~2O with Sb~2O~3 and Ce(NO~3)~3.6H~2O. The structure of heteropolyanion Ce~3Sb~4W~2O~8(H~2O)~1~0(SbW~9O~3~3)^1^9^-~4 is determined by X-ray diffraction analysis and elemental analysis. The cell parameters of [Ce~3Sb~4W~2O~8(H~2O)~1~0(SbW~9O~3~3)~4](NH~4)~1~9.48H~2O: a=1.8908(6) nm, b=2.0032(14) nm, c=2.8653(12) nm, α=86.95(6)°, β=75.68(3)°, γ=67.52(5)°, V=9.706(9) nm^3, space group P1. The [Ce~3Sb~4W~2O~8(H~2O)~1~0(SbW~9O~3~3)~4]^1^9^- anion possesses a large center group [Ce~3Sb~4W~2O~8(H~2O)~1~0]^1^7^+ attached by four β-B-(SbW~9O~3~3)^9^-, the center group contains three Ce(Ⅲ), two bridging {WO~2(H~2O)} groups and one {Sb~4O~4} group. The coordination number of all three Ce(Ⅲ) is nine however their coordination circumstances are different: Ce(1) and Ce(3) have the same coordination circumstance in which the cerium atoms are coordinated by four oxygen atoms of two (SbW~9O~3~3)^9^-, one oxygen atom of {Sb~4O~4}, one oxygen atom of one bridging {WO~2(H~2O)} and two oxygen atoms of two water molecules. Four antimony atoms form a tetrahedron in {Sb~4O~4} group. The anion belongs to C~s point group.