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1.
Heteropoly complexes K11[Ln(CaW 11O39H2)21 · x H2O(Ln=La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy ) have been prepared and analysed. Some properties such as thermal behavior, IK and UV spectra, X-ray powder diffraction, magnetic susceptibility and X-ray photoelectron spectrum have been investigated. 相似文献
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1 INTRODUCTION Polyoxometalates are the unique metal-oxygen clusters composed of transition metals in groups V and VI (Mo, W, V, Nb, Ta) in a high oxidation state showing a large structural varieties as well as inte- resting physical and chemical properties in diverse fields including catalysis, analytical chemistry, nanotechnology, chemical sensing, biochemical and geochemical processes, medicine and materials science[1~5]. Recently, there has been increasing interest in the synthesis… 相似文献
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1 INTRODUCTION Though the investigation on chemistry of tran- sition metal-peroxy complexes has been extensively carried out, up to now, only four structures of purely inorganic dimeric peroxovanadates have been deter- mined by single-crystal X-ray meth… 相似文献
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ZHAO Shi-Long ZHANG Han-Hui② HUANG Chang-Cang LIN Zheng-ZhongSUN Rui-Qing ZHENG Xiao-Ling LIN Zhi-Hua WU Xiao-Yuan 《结构化学》2001,20(6)
1 INTRODUCTION The pseudoliquid character of heteropoly compounds as catalysts is determined by their crystallographic properties. Study on the crystal structures of the heteropoly compounds could provide interesting information to enrich heteropoly acid and catalytic chemistry[1]. In the past, Zhuo Ying-Li抯 group has synthesized the carbamidine salts of 1:1 LnL(Ln=lanthanide, L=[SiW11O39]n-)[2], and Pope抯 group has reported that -SiW11O39 units are connected by lanthanide catio… 相似文献
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《Journal of Coordination Chemistry》2012,65(11):1183-1190
A chain-like structure compound [4,4′-bipyH2]2[4,4′-bipyH][PCoW11O39]?·?H2O, in which lacunary polyoxoanions are joined by a Co–O–W bridge, was prepared through the hydrothermal method and characterized by IR, and X-ray crystallography. The title compound crystallizes in a monoclinic lattice, P21/n space group, with a?=?13.643 (3), b?=?27.052(5), c?=?15.180(3)?Å, β?=?100.63(3)°, V?=?5506.2(19)?Å3, Z?=?4, R 1?=?0.0792, wR 2?=?0.1532. Cobalt-substituted Keggin-type subunits are connected via Co–O–W bridges to form a 1D, chainlike, polymolecular Keggin POM. TG-DTA analysis indicates the title compound decomposes at 553°C. 相似文献
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A novel transition metal ion bridging bis(diphosphopentamolybdates) has been synthesized and characterized by elemental analysis,IR spectrum,UV spectrum and single-crystal X-ray diffraction.The single-crystal structure analysis shows that the compound consists of seven charge-compensating 2,2'-biimidazole cations (BIIM=2,2'-biimidazole) and one dumbbell-like [Mn(H2O)4(P2Mo5O23)2]10-heteropolyanion which is constructed by two [P2Mo5O23]6-clusters bridged through one [Mn(H2O)4]2+ cation. 相似文献
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《结构化学》1992,(2)
<正> K7H6[Nd(GeMo11O39)2]·27H2O, Mr = 4413.8, crystallizes in monoclinic, space group P21/n with a = 17. 095(4), b = 26. 895(3), c = 21. 214(5) (?); β=103. 11(2)°;V = 9499. 4(3)(?)3; F(000) = 8808; Z = 4; Dc = 3. 05g/cm3; μ(MoKα) = 43. 7cm-1 and λ=0. 71069(?). A total of 8644 reflections with I≥3σ(I) were used in the structure analysis. The final R value is 0. 090, Rw value is 0. 091. The atom Nd is situated between two tetradentate heteropoly (GeMo11O39)8- ligands to form the anion [Nd(GeMo11O39)2]13-. Nd is surrounded by eight oxygen atoms at average distances of 2. 446 (?), forming a square antiprism. 相似文献
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Thetrimolybdenumclusterswithgeneralformula[Mo3(μ3S)(μS)3(μdtp)(dtp)3L](dtp=(S2P(OC2H5)2)-,L=H2O,py,SC(NH2)2etc.)[1](referredtoasM1type[2]),and[Mo3(μ3S)(μS2)3(dtp)3]X(X=Cl,I)[3](referredtoasM2type),aretwomaintypesoftrimolybdenumclusterseverinvestigatedbyourresearchgroup.Aswehavealready… 相似文献
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ZHANG Xin~ YOU Wan-sheng~ ** ZHU Zai-ming~ DANG Li-qin~ SUN Zhen-gang~ ZHENG Xue-fang~ . Institute of Chemistry for Functionalized Materials Faculty of Chemistry Chemical Engineering Liaoning Normal University Dalian P. R. China . Liaoning Key Laboratory of Bio-organic Chemistry Dalian University Dalian P. R. China 《高等学校化学研究》2007,(1)
IntroductionPolyoxometalates are used as the versatile inorga-nic building blocks for the construction of molecular-based materials[1—7]. Nanosized polyoxometalates aresuitable building blocks for the construction of crystal-line microporous structural m… 相似文献
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《Journal of Coordination Chemistry》2012,65(15):2428-2436
A heteropolyoxotungstate, [Cu(en)2]2H8[Gd(PW11O39)2] ·?(H2en)0.5 ·?3H2O (1), has been hydrothermally synthesized and characterized by IR, XPS, TGA and single-crystal X-ray diffraction. Compound 1 crystallizes in the triclinic system, space group P 1, with a =?12.651(2) Å3, b =?20.559(3) Å3, c =?21.729(3) Å3, α =?71.379(2), β =?82.829(2), γ =?75.532(2)°, V =?5179.5(14) Å3, Z =?2, R 1 =?0.0702 and ωR 2 =?0.1479. The heteropolyanion is composed of two monovacant [α-PW11O39]7? Keggin moieties linked via a Gd atom leading to a sandwich-type structure. The Gd center is in a distorted square antiprismatic coordination environment with eight oxygen atoms, four from each of the two [α-PW11O39]7?moieties. 相似文献
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Two novel heteropolymolybdate, [H2bpy]2 [Hbpy] [PCuMo11O39]·H2O 1 and [H2bpy]2 [Hbpy] [PZnMo11O39]·2.75H2O 2, have been prepared under mild hydrothermal conditions and structurally characterized by single-crystal X-ray diffraction. The two compounds are isostructural and crystallize in the monoclinic space group P2(1)/n (No. 14) with a=13.440(3) Å, b=26.660(5) Å, c=15.240(3) Å, β=99.55(3)°, and Z=4 for the compound 1, and a=13.610(3) Å, b=26.781(5) Å, c=15.205(3) Å, β=100.40(3)°, and Z=4 for the compound 2. Compound 1 and 2 exhibit a zigzag chain structure in which Keggin anions are connected through a common oxygen atom. They are the first characterized compounds containing 1D chains of transition-metal substituted Keggin heteropolymolybdate. Other characterizations by elemental analysis, IR, EPR, TG, and XRPD are also described. 相似文献
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A cobalt paradodecatungstate [Co(H2O)5]2[Co(H2O)4]3[H2W12O42]·11H2O has been successfully synthesized and structurally characterized by X-ray crystallography. Structure analysis indicates that the title compound is of monoclinic, space group P21/n, with a = 13.449(3), b =19.585(4), c = 13.990(3) (A),β = 113.79(3)°, V = 3371.8(12) (A)3, Z= 2, R= 0.0519 and wR= 0.1242.The title compound exhibits a novel 3D extended network structure constructed by interconnecting the paradodecatungstate polyanion [H2W12O42]10- clusters and cobalt11 coordination ions. 相似文献
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A novel hybrid tungstocuprate(Ⅱ) [Cu(2,2'-bpy)3]2H4[CuW12O40]·6H2O(2,2'-bpy=2,2'-bipyridine) was synthesized via hydrothermal method and characterized using elemental analyses, IR, UV, XPS, TG-DSC, EPR, and X-ray single crystal diffraction. The structural analysis shows that the complex consists of an unusual Keggin-type polyoxoanion [CuW12O40]6- and a pair of chiral complex cations [Cu(2,2'-bpy)3] together with four protons and six crystallization water molecules, and the Keggin polyoxoanion is connected with [Cu(2,2'-bpy)3] via multiple C-H…O hydrogen bonds resulting in a dimer. 相似文献
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A 3D infinitely extended structural rare earth coordination compound with a formula of K3{[Sm(H2O)7]2Na[α-SiW11O39Sm(H2O)4]2}·14H2O has been synthesized by reaction of Sm2O3, HClO4, NaOH with α-K8SiW11O39·nH2O, and characterized by IR,UV spectra, ICP, TG-DTA, cyclic voltammetry, variable-temperature magnetic susceptibility and X-ray single-crystal diffraction.X-ray single-crystal diffraction indicates that the title compound crystallizes in a triclinic lattice, Pī space group, with a=1.2462(3) nm, b=1.2652(3) nm,c=1.8420(4) nm,α=87.45(3)°,β=79.91(3)°,γ=82.57(3)°,Z=1, R1=0.0778,wR2=0.1610.Structural analysis reveals that Sm3+(1) coordination cation has incorporated into the vacant site of [α-SiW11O39]8- entity,forming the [α-SiW11O39Sm(H2O)4]5- subunit.The two adjacent [α-SiW11O39Sm(H2O)4]5- subunits are combined with each other through two Sm(1)-O-W bridges accompanying the formation of dimmer structural unit [α-SiW11O39Sm(H2O)4]210- of the title compound.The neighboring dimmer structural units [α-SiW11O39Sm(H2O)4]210- are linked to form the 1D chainlike structure by means of two Sm3+(2) and a Na+(1) coordination cations.The K+(1) cations connect the 1D packing chains constructing the 2D netlike structure, and adjacent netlike layers are also grafted by K+(2) cations to build the novel 3D infinitely extended structure.The result of TG-DTA curves manifests that the decomposition temperature of the title polyanionic framework is 554℃.The cyclic voltammetry measurements show that the title polyanion has the two-step redox processes in aqueous solution with pH=3.1.Variable temperature magnetic susceptibility indicates the title compound obeys the Cruie-Weiss Law in the higher temperature range from 110 to 300 K, while in the lower temperature range from 2 to 110 K the comparatively strong antiferromagnetism interactions can be observed. 相似文献
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新型超分子化合物[H2N(CH2)6NH2](H3O)4[PMoVI7MoV5O40(VIVO)2]晶体的水热合成与表征 总被引:1,自引:2,他引:1
在水热条件下合成了一种新型超分子化合物,通过元素分析、红外光谱、热重分析和X射线单晶衍射方法确定了其晶体结构.结构分析表明该晶体属于单斜晶系,C2/m空间群,晶胞参数a = 1.264 3(3) nm, b = 2.106 9(4) nm, c = 1.005 7(2) nm, α = 90°, β = 110.16(3)°, γ = 90°, V = 2.514 9(9) nm3, Z = 2, R1 = 0.061 8, wR2 = 0.179 4. 相似文献
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The synthesis, spectral properties and crystal structures of Cs2[W(bpy)(CN)6]·2H2O and (AsPh4)2[W(bpy)(CN)6]·3.5H2O are described. The anions of both salts show distorted antiprismatic geometry with very similar bond lengths and angles. The structure of the [W(bpy)(CN)6]2– anion is independent of the type of cation, in contrast to the octacyanotungstate(IV). 相似文献
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研究了多金属氧酸盐分子基化合物K3[Cr3O(OOCH)6(H2O)3][α-GeW12O40]·17H2O的合成、晶体结构及其结晶水可逆脱附和吸附性能.该化合物属于单斜晶系,C2/m空间群,α=2.738
3(6)nm,b=1.58 3 0(3)nm,c=1.730 4(4)nm,β=102.43(3)°,V=7.325(3)nm3,Z=4,R1(wR2)=0.067
8(0.171 9).该晶体具有孔道结构,孔道内的结晶水能够可逆的脱附和吸附,而晶体结构随之恢复,因此具有分子筛的特性. 相似文献
