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Ganglin Xue Bin Liu Huaiming Hu Jianhui Yang Jiwu Wang Feng Fu 《Journal of Molecular Structure》2004,690(1-3):95-103
A new family of heteropolytungstate complexes (NH4)21[Ln(H2O)5{Ni(H2O)}2As4W40O140]·xH2O(Ln=Y, Ce, Pr, Nd, Sm, Eu, Gd) were prepared by the reaction of Na27[NaAs4W40O140]·60H2O with NiCl2·6H2O and Ln(NO3)3·xH2O at pH≈4.5. The crystal structures of (NH4)21[Gd(H2O)5{Ni(H2O)}2As4W40O140]·51H2O was determined by X-ray diffraction analysis and element analysis. The compound crystallizes in the monoclinic space group P21/n with a=19.754(3), b=24.298(4), c=39.350(6) Å, β=100.612(3)°, V=18564(5) Å3, Z=2, R1(wR2)=0.0544(0.0691). The central site S1 and two opposite sites S2 of the big cyclic ligand [As4W40O140]28− are occupied by one Ln3+and two Ni2+, respectively, each site supply four Od coordinating to metal ion, another one water molecule and other five water molecules coordinate, respectively, to Ni2+and Ln3+. Polyanion [Ln(H2O)5{Ni(H2O)}2As4W40O140]21− has C2v symmetry. IR and UV–vis spectra of [NaAs4W40O140]27− of the title compounds are discussed. 相似文献
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Photoluminescent multilayers were fabricated by layer-by-layer deposition between europium-substituted heteropolytungstate K13[Eu(SiW11O39)2]·28H2O (denoted ESW) and a cationic polymer of quaternized poly(4-vinylpyridine) partially complexed with osmium bis(2,2′-bipyridine) (denoted as QPVP-Os) on glassy carbon and quartz substrates. The resulting photoluminescent organic-inorganic hybrid multilayers were characterized by electrochemical impedance spectroscopy, UV-Vis absorption spectrometry, cyclic voltammetry and photoluminescence spectra. Electrochemical impedance spectroscopy, UV-Vis absorption spectrometry and cyclic voltammetry results demonstrated that the multilayers were regular growth each layer adsorption. The photoluminescent properties of the films at room temperature were investigated to show the characteristic Eu3+ emission pattern of 5D0→7Fj. 相似文献
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Three new extended iron‐containing heteropolytungstates were synthesized and structurally characterized: K6[{FeII(H2O)4}2(H2W12O42)]·15H2O ( 1 ), Na5[{Fe(H2O)3}2{Fe(H2O)4}0.5(H2W12O42)]·30H2O ( 2 ) and (H3O)+2[{Fe(H2O)4Fe(H2O)3}2(H2W12O42)]·20H2O ( 3 ). 1 and 3 crystallize in the monoclinic system, space group P21/n with a = 14.9967(5), b = 10.3872(3), c = 18.8237(6)Å, β = 93.407(1)°, V = 2927.1(2)Å3 and Dc = 4.151 g cm—3 for 1 , and space group P21/c with a = 12.1794(4), b = 22.4938(4), c = 11.6941(3) Å, β = 105.731(2)°, V = 3083.7(1) Å3, and Dc = 4.043 g cm—3 for 3 . 2 is triclinic, space group P1¯, with a = 12.121(2), b = 12.426(3), c = 13.247(3)Å, α = 68.33(3), β = 71.33(3), γ = 71.44(3)°, V = 1710.7(6)Å3 and Dc = 3.735 g cm—3. In all cases, the structures are based on paradodecatungstate polyoxoanions, which are linked by iron ions into chains, layers and a three‐dimensional structure for 1 , 2 and 3 , respectively. 相似文献
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Jing Xin Meng Ying Ma Xin Xin Xu Yang Guang Li En Bo Wang~* Key Laboratory of Polyoxometalate Science of Ministry of Education Department of Chemistry Northeast Normal University Ren Min Street No. Changchun Jilin PR China 《中国化学快报》2007,18(1):81-84
A new heteropolytungstate,[H_2bpy]_3[SiMnW_(11)O_(39)].1.25H_2O(1),has been prepared under mild hydrothermal conditions and structurally characterized by single crystal X-ray diffraction.It is the first characterized compound containing 1D zigzag chain of transition metal substituted Keggin heteropolytungstate,which is connected through a common oxygen atom.The elemental analysis and IR of it are also described. 相似文献
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本文报道了α和β-[SiW_9O_(37)M_3(H_2O)_3]~((?))(M=Al~(3+),Ga~(3+),In~(3+))钾、铯盐的合成和性质。6种化合物的钨-183核磁共振谱都含有2个峰,相对强度为2∶1,表明其阴离子分别具有Aα和Aβ型Keggin结构,即3个MO_6八面体是角顶共用。 相似文献
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SynthesisandCharacterizationofTri(organotin)SubstitutedHeteropolytungstatesYANGQi-hua,DAIHui-cong,LIUJing-fu(DepartmentofChem... 相似文献
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Three novel scandium-containing heteropolytungstates[Sc3(H2O)3NO3(PW9O34)2]10-(1a),[Sc8(H2O)2(GeW9O34)2(GeW6O26)2]12-(2a) and[Sc11(W6O10)2(OH)2(H2O)16(BiW9O33)6]27-(3a) were synthesized by reactions of ScIII ions with trilacunary Keggin precursors,[A-α-XW9O34]n-(X=P, Ge, n=9, 10) or[B-α-BiW9O33]9-, in NaOAc/HOAc buffer solution under conventional synthetic condition, respectively. All the three compounds were characterized by means of single-crystal X-ray diffraction(XRD), Fourier transform-infrared(FTIR) spectroscopy ultraviolet-visible(UV-Vis) spectroscopy, elemental analysis, and thermogravimetric analysis. The aqueous solution stability of the sandwich polyanion[Sc3(H2O)3NO3(PW9O34)2]10- was also verified by electrospray ionization mass spectrometry(ESI-MS) due to its good solubility in water. 相似文献
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Majid Masteri-Farahani Melika Ghorbani Ali Ezabadi Niki Farrokhinia Atekeh-Sadat Ghaemmaghami 《Comptes Rendus Chimie》2014,17(11):1136-1143
In this work, we report the novel successful preparation of the Keggin-type Cs(CTA)2PW12O40 (CTA = cetyltrimethylammonium cation) nanostructure by a microemulsion method. The microemulsion system included the cationic surfactant CTAB, 1-butanol as co-surfactant, isooctane as oil phase, and an aqueous solution containing CsNO3. The Cs(CTA)2PW12O40 nanostructure was formed by the addition of an aqueous solution of phosphotungstic acid to the microemulsion solution. Characterization of the resultant nanostructure was done using FT–IR spectroscopy, X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray analysis, and CHN elemental analysis. The product was found to be a star-shaped nanostructure composed of some nanorods whose diameter and length are about 100 nm and 500 nm, respectively. The prepared nanostructure was used as a recoverable catalyst for the synthesis of quinoxaline derivatives by the condensation of 1,2-diamines with 1,2-dicarbonyl compounds, which afforded the products in good to high yields in short reaction times. 相似文献
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镧系元素的杂多钨钛酸盐的合成与性质研究 总被引:8,自引:0,他引:8
自1971年Peacock等首次合成以不饱和杂多阴离子作配体的镧系元素杂多配合物[Ln(XW_(11)O_(39)]~(n-)(X=Si,P)以来,这方面的报道较多。过渡元素的引入有可能改善这类化合物的某些活性,尤其是催化活性,但迄今为止尚未见报道,本文首次合成出以TiW_(11)O_(39)~(3-)为配体的镧系元素杂多钨酸盐K_(13)[Ln(TiW_(11)O_(39))_2]·xH_2O(Ln=La,Ce,Pr,Nd,Sm,Eu),并对其IR、UV光谱及热、磁性质进行了测试和初步研究。 相似文献
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Zhi Huan Weng Jin Yan Wang Xi Gao Jian 《中国化学快报》2007,18(8):936-938
A series of heteropolytungstates has been synthesized and utilized as catalysts to catalyze oxidation of benzyl alcohol with aqueous hydrogen peroxide.The results indicated that three of these catalysts showed the properties of reaction-controlled phase- transfer catalysis,and they had excellent catalytic ability to the oxidation of benzyl alcohol.No other by-products were detected by gas chromatography.Once the hydrogen peroxide was consumed completely,the catalyst precipitated from solvent,and the results of the catalyst recycle showed that the catalyst had high stability. 相似文献
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