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1.
Three inorganic–organic composite sandwich-type phosphotungstates [Ni(tepa)(H2O)]4H2[Ni4(H2O)2(α-B-PW9O34)2]·8H2O (1), (enH2)3[Ni2(H2O)10][Ni4(H2O)2(α-B-PW9O34)2]·en·8H2O (2) and (enH2)10[Mn4(H2O)2(α-B-PW9O34)2]2·20H2O (3) (tepa=tetraethylenepentamine and en=ethylenediamine) have been synthesized by the hydrothermal reaction of the trivacant Keggin polyoxoanion [α-A-PW9O34]9− with Ni2+ or Mn2+ ions in the presence of tepa or en and structurally characterized by IR spectra, elemental analysis, thermogravimetric analysis and variable temperature magnetic susceptibility. X-ray crystallographic analyses indicate that they all contain the classical tetra-M sandwiched polyoxoanions [M4(H2O)2(α-B-PW9O34)2]10− (M=Ni2+ or Mn2+) and nickel-organoamine cations or organoamine cations work as the charge balance ions. The tetra-M clusters in 1, 2 and 3 exhibit the familiar structural type of a β-junction at the sites of metal incorporation. The study of magnetic property of 1 is indicative of a typical ferromagnetic coupling between Ni2+ cations.  相似文献   
2.
In the presence of NBu4nBr acting as phase-transfer reagent, organosilicon trichloride C2H5SiCl3 reacts in acetonitrile with the trivacant tungstophosphate sodium salt β-A-Na8H[PW9O34]·24H2O to give hybrid organosilyl polyoxotungstate derivative α-A-[NBu4n]3[PW9O34(C2H5SiO)3(C2H5Si)]. X-ray single crystal structural analysis indicates that the title compound is monoclinic, space group Cc, with lattice constants a=26.828(5), b=22.459(5), c=17.517(4) Å, β=103.19(3)°, V=10,276(4) Å3, Z=4, R=0.0462. According to the result of X-ray single crystal diffraction and chemical analysis, the hybrid polyanion consists of one α-A-[PW9O34]9− framework on which are grafted simultaneously three RSiO groups through six Si-O-W bridge bonds, each of which is attached to the fourth RSi group through three Si-O-Si bridge bonds. The hybrid polyanion becomes a partial saturated, closed cage structure and also has an assembly of virtual C3V symmetry.  相似文献   
3.
Two new organic–inorganic composite sandwich-type arsenotungstates [H2dap]6H8[Ni4(H2O)2(B-α-AsW9O34)2]2 · 33H2O (1) and {[Ni(dap)2(H2O)]2[Ni(dap)2]2[Ni4(Hdap)2(B-α-AsW9O34)2]} · 4H2O (2) (dap = 1,2-diaminopropane) have been hydrothermally synthesized by reaction of Na8[A-α-HAsW9O34] · 11H2O with NiCl2 · 6H2O in the presence of 1,2-diaminopropane and characterized by elemental analysis, IR spectra, X-ray single-crystal diffraction, and thermogravimetric analysis. 1 crystallizes in the triclinic P 1 space group with a = 16.351(6) Å, b = 16.423(6) Å, c = 19.894(7) Å, α = 110.630(6)°, β = 92.684(7)°, γ =104.946(7)°, V = 4774(3) Å3, Z = 1, GOOF = 1.033, R 1 = 0.0517, wR 2 = 0.1086. 2 also crystallizes in the triclinic P 1 space group with a = 13.305(4) Å, b = 13.882(4) Å, c = 17.031(5) Å, α = 68.109(5)°, β = 71.511(4)°, γ = 88.407(5)°, V = 2753.5(14) Å3, Z = 1, GOOF = 1.051, R 1 = 0.0491, wR 2 = 0.1150. Notably, 1 is a discrete structure, composed of two tetra-NiII substituted sandwich-type polyoxoanions [Ni4(H2O)2(B-α-AsW9O34)2]10? with different spatial orientation, whereas 2 displays a organic–inorganic composite 2-D sheet architecture constructed by tetra-NiII sandwiched [Ni4(H2O)2(B-α-AsW9O34)2]10? units by means of [Ni(dap)2]2+ bridges. Some previously reported transition-metal-substituted sandwich-type polyoxotungstates have been summarized.  相似文献   
4.
合成了三缺位杂多阴离子的苯基硅衍生物 (TBA) 3[α-A-PW9O34 (Ph Si O) 3(Ph Si) ]· 2 H2 O(记为 1 ,TBA为四丁基铵阳离子 ) ,并由元素分析、红外光谱、紫外光谱对化合物进行了表征 ,研究了化合物的热性质 .结构分析结果表明 ,该化合物属三方晶系 ,空间群 R3,晶胞参数 a=1 .41 696(1 6) nm,b=1 .42 1 63 (1 6)nm,c=1 .41 661 (1 6) nm,α=99.80 1 (1 7)°,β=99.843 (1 7)°,γ=99.844(1 7)°,V=2 .71 1 1 (5 ) nm3.Z=1 ,R=0 .0 5 48.该化合物的阴离子是由 1个α-A-PW9单元 ,通过 6个 W— O— Si桥键与 3个 Ph Si O单元相连 ,3个 Ph Si O又通过 Si— O— Si桥键与另 1个处于帽位的 Ph Si相连 ,形成饱和闭合笼形结构  相似文献   
5.
The reaction of SiW9O10-34 and GeW9O10-34 with metal cations leads to Keggin trisubstituted polyoxoanions.A review of all known trisubstituted Keggin anions demonstrates characteristic patterns of 183W NMR chemical shifts.  相似文献   
6.
三空位杂多阴离子SiW9O10-34有α和β两种异构体[1],β-SiW9O10-34阴离子钠盐的晶体结构测定表明,它是β-SiW12O4-40阴离子的缺位衍生物,是从β-SiW12O4-40阴离子中去掉3个WO6八面体后形成的含3个空位的杂多阴离子...  相似文献   
7.
Abstract  Two novel organic–inorganic composite phosphotungstates, [H9{Ce(α-PW11O39)2}Cu(en)2] · 6H2O (1) and H7[Cu(en)2{Er(α-PW11O39)2}Cu(en)2] · 12H2O (2) (en = ethylenediamine) have been synthesized by the hydrothermal reaction of the trivacant Keggin polyoxoanion [α-A-PW9O34]9− with CeIII or ErIII ions in the presence of Cu2+ ions and en, and structurally characterized by IR spectra, elemental analysis and thermogravimetric analysis. X-ray crystallographic analyses indicate that they are all built by sandwich-type [Ln(α-PW11O39)2]11− (Ln = CeIII, ErIII) polyoxoanions and [Cu(en)2]2+ cations generating infinite one-dimensional arrangements. To our knowledge, this 1-D chain structures constituted by mono-Ln sandwiched POM units and transition-metal complex cations are very rare. Graphical Abstract  Two novel organic–inorganic composite phosphotungstates, [H9{Ce(α-PW11O39)2}Cu(en)2] · 6H2O (1) and H7[Cu(en)2{Er(α-PW11O39)2}Cu(en)2] · 12H2O (2) (en = ethylenediamine) have been synthesized by the hydrothermal reaction of the trivacant Keggin polyoxoanion [α-A-PW9O34]9− with CeIII or ErIII ions in the presence of Cu2+ ions and en, and structurally characterized by IR spectra, elemental analysis and thermogravimetric analysis. X-ray crystallographic analyses indicate that they are all built by sandwich-type [Ln(α-PW11O39)2]11− (Ln = CeIII, ErIII) polyoxoanions and [Cu(en)2]2+ cations generating infinite one-dimensional arrangements. To our knowledge, this 1-D chain structures constituted by mono-Ln sandwiched POM units and transition-metal complex cations are very rare.   相似文献   
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