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1.
含有钒和钼的化合物在催化、抗病毒药物、功能材料等领域具有广阔的应用前景 [1~ 4 ] .近年来 ,钒取代的杂多化合物或金属 -氧簇的合成与表征已引起人们的广泛关注 ,许多新的化合物已被合成 ,如含五价钒的化合物 K7[Mo8V5O4 0 ]· 8H2 O和 Na3[VMo12 O4 0 ]· 1 9H2 O[5,6 ] ,含有混合价态钒的簇阴离子[( V V Mo10 ) VO4 0 ]6 - 和 [Mo8V V4 O4 0 ]8- 的化合物 [7,8] ,含双帽 Keggin 结构的簇阴离子[PMo6 VMo6 O4 0 ( V O) 2 ]5- 和 [PMo8V 4 V 2 O4 2 ]5- 的化合物 [9,10 ] 等 ,但所报道的含混合价态钒的 V- Mo化合物中含…  相似文献   

2.
尽管多金属氧酸盐 (POMs)的研究已有 1 80多年的历史 ,但大量的 POMs结构在最近几十年才被陆续解析出来 [1~ 4 ] .其中 ,同多钒酸盐由于钒配位几何形状的多样性 ,结构最为丰富 ,例如 :[V4 O12 ]4- [5] ,[V5O14 ]3 - [6] ,[V10 O2 8]6- [7] ,[V15O4 2 ]9- [8] ,[V13 O3 4 ]3 - [9] .值得注意的是 ,在这些化合物中 ,钒的化合价均处于最高氧化态 +5价 .由于 +4价钒不易在溶液中 (尤其是水中 )稳定存在 ,因此在以往的常压溶液合成中具有混合价态的同多钒酸盐报道很少 .与饱和价态的同多钒酸盐相比 ,混价多钒酸盐具有更为新奇的电荷分布…  相似文献   

3.
具有Dawson结构的钼钒磷杂多酸的制备和性质研究   总被引:20,自引:0,他引:20  
本文报道用改良的分步处理合成方法, 直接制备了五种未见报道的2:18系列钼钒磷杂多酸, 详细考察了它们的生成条件. 经元素分析、电位滴定和差热热重分析确定阴离子的组成分别为[P2Mo17VO62]^7^-,[P2Mo16V2O62]^8^-,[P2Mo15V3O62]^9^-, [P2Mo14V4O62H2]^8^-, [P2Mo13V5O62H2]^9^-. 对五种杂多酸的热化学性质和碱度进行了讨论. 根据紫外、红外及X射线衍射结果讨论了它们的结构, 表明都属于具有Dawson结构的杂多化合物.  相似文献   

4.
利用水热合成方法制备了Keggin结构多金属氧酸盐[Mn(phen)3]2(H3O)·2H2O,用元素分析、红外光谱、热分析和X射线单晶衍射测试技术对其结构进行了表征. 结果表明,该化合物属于单斜晶系,C2/c空间群,a=2.728 5(3) nm,b=2.506 0(3) nm,c=1.633 6(18) nm,β=104.911(2)°,V=10.79 4(2) nm3,Z=4,R1=0.078 4,wR2=0.199 9. 化合物分子结构单元由1个Keggin结构多金属氧酸盐阴离子5-,2个配位阳离子[Mn(phen)3]2+,1个质子和2个结晶水分子构成. 化合物分子之间通过π-π堆积作用形成了三维超分子结构.  相似文献   

5.
IntroductionLayered intercalation compounds haveattracted increasing research attention due to theirapplications in diverse areas,for instance,some ofthem are used as rechargeable batteries,heterogeneous catalysts,and an exchange[1— 12 ] . Inprevious literatures,several layered mixed- valencevanadium oxides were reported,such as VO2 · 1 /2 H2 O[13 ] ,[H2 N( CH2 ) 4 NH2 ]V4O9[14 ] ,NH4V3 O8[15] ,( C6H14 · N2 ) V6O14 · 1 / 2 H2 O[16] ,[HN( C2 H4) 3 NH]V6O14 [17] ,NMe4V6O14 [18]…  相似文献   

6.
钒氧化合物由于其有趣的阴离子结构和在催化反应、药物化学以及材料科学等领域中的应用而受到人们的关注[1,2].近年来,一些具有1D链、2D层和3D开放骨架结构的钒氧化合物陆续被报道[3~7].由于柔软的V—O—V键和其可调变的多面体,一些金属原子(如W,Mo,P,As等)可被引入钒氧团簇而形成异构的或新的氧簇结构.在笼状的[As8V14O42]4-阴离子中可包含一些小的无机分子(如SO23-、SO42-、H2O或HPO24-)[8~14].我们[10]曾报道了[As8V14O42]4-笼内包含HPO4基团的化合物[Co(en)3]2·2H3O·[As8V14O42(HPO4)]·2H2O.本文通过在As-V反应体系…  相似文献   

7.
合成了标题化合物[Cu(enMe)2]4[H5VⅣ18O42(Cl)]·8H2O 1,晶体属于四方晶系,P4/nnc空间群,晶胞参数a = 15.0034(3), c = 18.8149(3) (A。), V = 4235.27(14) (A。)3, Z = 2, Dc = 2.055 g/cm3, Mr = 2620.74, μ= 2.988 mm-1, F(000) = 2608, R = 0.0766, wR = 0.2118, S = 1.193, (Δρ)max = 0.969×103 , (Δρ)min = -0.454×103 e/(A。)3.化合物1的阴离子[VⅣ18O42(Cl)]8-通过金属配合物阳离子[Cu(enMe)2]2+连接形成3-D骨架结构.  相似文献   

8.
多金属氧酸盐在催化、医药和材料等方面的应用越来越成为无机化学研究的热点[1~5].水热合成技术在合成多核金属氧酸盐中有独特的优点.在众多的钼钒酸盐中,只有几种双帽及四帽Keggin结构被合成出来[6~13].本文报道一种含有不同配位阳离子的四帽Keggin结构砷钼钒酸盐[Co(en)3]·[Co(en)2(H2O)2]2·[Mov4MoⅥ4VⅣ8O40(AsO4)]的合成与结构.该化合物的结构是由不同的阳离子--1个[Co(en)3]3+和2个[Co(en)2(H2O)2]2+及簇阴离子[Mov4MoⅥ4VⅣ8O40(AsO4)]5-构成的.[Mo8V8O40(AsO4)]5-簇阴离子具有四帽"Keggin"结构,两对V原子位于4个"双帽"位置,簇笼中央是1个{AsO4}四面体.  相似文献   

9.
合成了砷钼夹心型化合物Na5[ (CH3)4N]3( H3O)2[ Co2( AsVMo9O33)2]·8H2O,用X-射线单晶衍射、元素分析和红外光谱对晶体的结构进行了表征.结构表征指出该化合物是由砷钼夹心型[ Co2(AsVMo9O33)2]10-多阴离子,( CH3 )4N+反荷阳离子,Na+反荷阳离子和结晶水分...  相似文献   

10.
多金属氧酸盐在催化、医药和材料等方面的应用越来越成为无机化学研究的热点[1~5].水热合成技术在合成多核金属氧酸盐中有独特的优点.在众多的钼钒酸盐中,只有几种双帽及四帽Keggin结构被合成出来[6~13].本文报道一种含有不同配位阳离子的四帽Keggin结构砷钼钒酸盐[Co(en)3]·[Co(en)2(H2O)2]2·[Mov4MoⅥ4VⅣ8O40(AsO4)]的合成与结构.该化合物的结构是由不同的阳离子--1个[Co(en)3]3+和2个[Co(en)2(H2O)2]2+及簇阴离子[Mov4MoⅥ4VⅣ8O40(AsO4)]5-构成的.[Mo8V8O40(AsO4)]5-簇阴离子具有四帽"Keggin"结构,两对V原子位于4个"双帽"位置,簇笼中央是1个{AsO4}四面体.  相似文献   

11.
金属磷酸盐材料在吸附、离子交换、离子传导和催化剂方面有潜在的应用前景[1~5]. 近年来, 通过水热反应合成了一些A-V-P-O化合物. 在这些化合物中, A一般为碱金属或有机阳离子, 如层状结构的[H2N(C4H8)2NH2][(VO)4(OH)4(PO4)2][6] 和[H2N(C2H4)3NH2][(VO)8(HPO4)3(PO4)4*(OH)2]*2H2O[6], 一维链状结构的 [H2NCH2CH2NH3(VO)(PO4)][7], 手性双螺旋结构的 [(CH3)2NH2]K4[(VO)10(H2O)2(OH)4(PO4)7]*H2O[8]以及具有三维骨架结构的化合物 [H3N(CH2)3NH3K(VO)3(PO4)3][9], [H3N(CH2)3NH3]2[V(H2O)2(VO)6(OH)2(HPO4)3(PO4)5]*3H2O[10]和[H3N(CH2)2NH3][(VO)3(H2O)2(PO4)2(HPO4)4][11].  相似文献   

12.
A pure inorganic [P2Mo5O23]6- based cobalt complex [H8(H2O)16][Co(H2O)4(HP2Mo5O23)2] with a sandglass-like shape was synthesized and characterized by means of single-crystal X-ray diffraction, powder X-ray diffraction(PXRD), infrared spectroscopy(IR), thermogravimetry/differential scanning calorimetry(TG/DSC), ultraviolet-visible spectroscopy(UV-Vis) and cyclic voltammogram(CV). Single-crystal X-ray diffraction analysis reveals that the asymmetric unit of compound 1 consists of a half cobalt ion, one [P2Mo5O23]6- anion, two coordinated water molecules and eight lattice water molecules. It is especially intriguing to note that two [P2Mo5O23]6- clusters are symmetrical about the Co ion, like a sandglass. And a chair-like water cluster with an unprecedented centrosymmetric [H8(H2O)16]8+ can be observed in compound 1. Additionally, the electrochemical and catalytic properties of compound 1 were also investigated.  相似文献   

13.
A new family of heteropolytungstate complexes (NH4)21[Ln(H2O)5{Ni(H2O)}2As4W40O140xH2O(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   

14.
The compound [Zn(H2O)4]2[H2As6V15O42(H2O)]·2H2O (1) has been synthesized and characterized by elemental analysis, IR, ESR, magnetic measurement, third-order nonlinear property study and single crystal X-ray diffraction analysis. The compound 1 crystallizes in trigonal space group R3, a=b=12.0601(17) Å, c=33.970(7) Å, γ=120°, V=4278.8(12) Å3, Z=3 and R1(wR2)=0.0512 (0.1171). The crystal structure is constructed from [H2As6V15O42(H2O)]4− anions and [Zn(H2O)4]2+ cations linked through hydrogen bonds into a network. The [H2As6V15O42(H2O)]6− cluster consists of 15 VO5 square pyramids linked by three As2O5 handle-like units.  相似文献   

15.
Three metal molybdate hydrates,Fe(H2O)2(MoO4)2·H3O(FeMo),NaCo2(MoO4)2(H3O2)(CoMo)and Mn2(MoO4)3·2H3O(MnMo),were synthesized by the mixed-solvent-thermal methods and characterized by singlecrystal X-ray...  相似文献   

16.
Abstract By reacting the unique Keplerate type molybdenum-oxide based polyoxometalate (NH4)42·[MoI320372·(CH3COO)30(H2O)y2]·ca.300H2·ca. 10CH3COONH4(1) with tetramethylammonium bromide, a new derivative (NH4)26[TMA]16{MoI32O372(H2O)72(CH3COO)30}·ca.7NH4CH3COO·ca.189H2O(2, TMA=tetramethylammonium) was prepared. Compound 2 was characterized by Fourier transform infrared spectroscopy(FTIR), UV-Vis, elemental and thermogravimetric analyses. By the well-established Z-scan technique, investigations on the nonlinear opti- cal(NLO) properties of the series of compounds derived from the Keplerate type molybdenum-oxide-based poly- oxometalate, namely, the newly prepared compound 2, the three previously reported compounds, included compound 1, (NH4hs(TBA)24{Mo132O372(H2O)72(CH3COO)30}·ca.7NH4CH3COO·ca. 173H2O(3, TBA=tetrabutylammonium) and (DODA)40(NH4)2[(H2O)nMo132O372(CH3COO)3o(H20)72](4, DODA=dimethyldioctadecylammonium), reveal that the third-order nonlinearity[x(3)] values of compounds 1, 2 and 3 in the DMF/H2O solution and compound 4 in chloro- form are almost the same, which indicates that the counter cations with different length of alkyl chains show ignora- ble impacts on the NLO susceptibility. In other words, the remarkable third-order nonlinearities[x(3)≈10 19 m2/V2] mainly come from the [MoI32O372(CH3COO)30(H2O)72]42 anions. This fact reveals that the applications of the NLO active polyoxometalates in various environments(such as hydrophilic, hydrophobic, polar, apolar, etc.) can be achieved by simply varying cations to meet the demands in the design of diverse devices. Keywords Keplerate type polyoxometalate; Nonlinear optical property; Z-Scan technique; Self-defocusing; Reverse saturable absorption  相似文献   

17.
Synthesis and Characterization of Zinc Succinate, Zn(C4H4O4)   总被引:3,自引:0,他引:3  
Introduction  Succinateion (C4H4O4) 2 -(—OOCCH2 CH2 COO— )isaversatileligandsinceeachofthefourterminalcarboxyloxygensisabletoparticipateincoordinationtocentralmetalatom(s)inadditiontotheflexibilityoftheC—Cbone .Suchcoordinatingversatilityhasbeenreflectedinseve…  相似文献   

18.
Three novel compounds, [Co(en)3]2[Zr2(C2O4)7]·2H20(HNU-2, en=ethylenediamine), [Co(NH3)6]· [Ce(CzO4)3(H2O)]·H2O(HNU-3) and [Co(dien)2][Gd(C2On)3]·0.75H2O(HNU-4, dien=dethylenetriamine) were hydro- thermal synthesized based on the templates of [Co(en)3]C13, [C0(NH3)6]C13 and [Co(dien)2]C13, respectively. The Zr4+ Ce3+ and Gd3+ cations are all coordinated by four oxalates to form [M(C2O4)n(H2O)n]m (M=Zr, Ce or Gd; n=0 or 1; m=4 or 5), which are similar to [In(C2O4)4]5- in NKB-1, and can be regarded as 4-connected building units. The [M(C2O4)a(H2O)n]m units are connected via sharing the bis-bidentate bridging oxalate ligands to form binuclears in HNU-2 and 1D "zigzag" chains in HNU-3 and HNU-4. cular building units to design 3D open frameworks with It is suggested that these compounds could be used as mole- zeolite topologies.  相似文献   

19.
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   

20.
Thermal decomposition of mixed ligand thymine (2,4-dihydroxy-5-methylpyrimidine) complexes of divalent Ni(II) with aspartate, glutamate and ADA (N-2-acetamido)iminodiacetate dianions was monitored by TG, DTG and DTA analysis in static atmosphere of air. The decomposition course and steps of complexes [Ni(C5H6N2O2)(C4H5NO4)2−(H2O)2]·H2O, [Ni(C5H6N2O2)(C5H7NO4)2−(H2O)2]·H2O and [Ni(C5H6N2O2)(C6H8N2O5)2−(H2O)2]·1.5H2O were analyzed. The final decomposition products are found to be the corresponding metal oxides. The kinetic parameters namely, activation energy (E*), enthalpy (ΔH*), entropy (ΔS*) and free energy change of decomposition (ΔG*) are calculated from the TG curves using Coats–Redfern and Horowitz–Metzger equations. The stability order found for these complexes follows the trend aspartate > ADA > glutamate.  相似文献   

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