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1.
IntroductionSupramolecularself organizationasacontrollabletechniquefortheartificialsupramoleculararchitectureatmolecularand/ornanosizedlevelisshowingfascinatingperspectivesinthefieldofthemolecularmaterialsde sign ,duetothatorganicandinorganiccomponents…  相似文献   

2.
1 INTRODUCTION The design and synthesis of organic-inorganic hy-brid compounds are of great interest owing to theirextensive theoretical and practical applications in ca-talysis, medicine, analytical chemistry, nanotechno-logy, electrochromism, magnetism and photochemis-try[1~5]. In heteropolyoxometalate chemistry, a newadvance is the decoration of polyoxoanions with va-rious organic and transition metal complex moieties.In contrast to a large number of known organic andtransition-metal-s…  相似文献   

3.
在常规条件下,以质子化的L,D-组氨酸修饰Dawson型多阴离子[P2Mo18O62]6-,得到了一对新型的氨基酸功能化的多金属氧酸盐化合物:H4(L-HC6H9N3O2)2[P2Mo18O62].20.5H2O(1),H4(D-HC6H9N3O2)2[P2Mo18O62].20.5H2O(2).并用单晶X射线衍射,紫外光谱(UV),红外光谱(IR),元素分析(Elemental Analysis)等方法对化合物进行了表征.  相似文献   

4.
Bis(tetramethylammonium) dodecahydrododecaborate, [(CH3)4N]2[B12H12], and bis(tetramethylammonium) dodecahydrododecaborate acetonitrile, [(CH3)4N]2[B12H12] · CH3CN, were synthesized and characterized via Infrared, 1H and 11B NMR spectroscopy. [(CH3)4N]2[B12H12] crystallizes isopunctual to the alkali metal dodecaborates. The crystal structure of [(CH3)4N]2[B12H12] · CH3CN was determined from single crystal data and refined in the orthorhombic crystal system (Pcmn, no. 62, a = 898.68(8), b = 1312.85(9) c = 1994.5(1) pm, R(|F| , 4σ) = 5.9%, wR(F2) = 18.3%). Here, the geometry of the dodecaborate anion is that of an almost ideal icosahedron, less distorted than most other dodecaborates known. By low‐temperature Guinier‐Simon diffractometry phase transitions were detected for [(CH3)4N]2[B12H12] and [(CH3)4N]2[B12H12] · CH3CN at –70 and –15 °C, respectively.  相似文献   

5.
标题晶体属斜方晶系,空间群Pbn2_1,a=9.086(2),b=13.439(3),c=22.858(11),V=2791,Z=4,Dc=1.927g/cm~3。在CAD—4衍射仪上收集强度数据,采用直接法和Fourier技术解出结构,并用全矩降最小二乘法修正。对于1180个独立衍射最终偏离因子0.067。结构中的阴离子与其同系物[(CH_3)_4-N]_2K(Mo_2O(S_2)_3(NO)_2]·H_2O中的阴离子配位情况相似。只是结构中的Mo—S与Mo—O键长有差异。这种差异在两者的红外光谱上有着相应的表现。  相似文献   

6.
7.
In the presence of N, N′‐dicyclohexylcarbodiimide (DCC), (Bu4N)2[Mo6O18(NAr)] ( 1 ) and (Bu4N)2[Mo6O17(NAr)2] ( 2 ), Ar = o‐CH3C6H4, have been synthesized via the reaction of [α‐Mo8O26]4— with o‐toluidine. If the hydrochloride salt of o‐toluidine was added into the reactive mixture, only the monofunctionalized imido derivative of [Mo6O19]2— was obtained; the bifunctionalized derivative of [Mo6O19]2— was exclusively synthesized in the presence of non‐protonated o‐toluidine. The molecular and crystal structures of the hybrid compounds 1 and 2 were determined by X‐ray single crystal diffraction, and their UV, IR and NMR spectra were compared. Additionally, a possible reaction mechanism was proposed.  相似文献   

8.
Methyl telluraalkanoates, CnH2n+1Te(CH2)mCOOR (n, m: 4, 7; 6, 4; 6, 7; 6, 9; 7, 4; 8, 7; 11, 2; 11, 5; 18, 11) were synthesized in yields ranging from 33 to 82 percent based on the quantities of the methyl ω-bromoalkanoates substrates. Disodium ditelluride was obtained from tellurium and sodium in ethylenediamine and was treated with alkyl bromides to give dialkyl ditellurides. The crude ditellurides were reduced with NaBH4 to the alkane tellurolates which were coupled with methyl ω-bromoalkanoates to give the methyl telluraalkanoates. Ethyl 4-tellurapentadecanoate was prepared similarly from ethyl 3-bromopropanoate. The telluraalkanoates were characterized by elemental analyses, mass spectrometry, NMR spectrometry, and UV and IR spectrophotometry. Telluraalkanoates radiolabeled with 123mTe or other radioisotopes have been reported elsewhere to be preferentially taken up by the heart and promise to be useful as myocardial imaging agents.  相似文献   

9.
10.
[CH3NH3][NH3(CH2)6NH3]H3[P2Mo2W16O62]·H2O的水热合成与表征   总被引:4,自引:0,他引:4  
首次合成了[CH3NH3][NH3(CH2)6NH3]H3[P2Mo2W16O62]·H2O,通过元素分析、红外光谱和X射线单晶衍射对合成产物进行了表征,并用TGA-DSC研究了化合物的热稳定性.晶体属单斜晶系,P21/m空间群,a=1.2596(3)nm,b=1.8715(4)nm,c=1.9816(4)nm,α=γ=90°,β=90.16(3)°,V=4.671(2)nm3,Z=2,Mr=4358.66,Dc=3.100g·cm-3,μ=19.978mm-1,F(000)=3792,R=0.0835,Rw=0.2026.结果表明,在晶体结构内形成了0.7364nm×0.8354nm的微孔.  相似文献   

11.
IntroductionTheexpensionofthecoordinationchemistryofpolyoxomolybdatesisattributedtothesolubilityofthepolyoxometallicanionsinorganicsolventsandcoordi nationabilityofthemascharacteristicmetalligandsinorgano metallicreactions ,forexample ,thestudyofcatalys…  相似文献   

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13.
由于在电学、磁学、光学、吸附、离子交换和催化等领域具有潜在的应用价值,具有开放骨架结构的金属磷酸盐的合成一直受到人们的广泛关注。在这些磷酸盐微孔化合物中,磷酸锌晶体是拓扑结构最为丰富的一种犤1犦。自从Stucky等犤2犦报道具有SOD、Li-ABW、FAU等已知结构磷酸锌的合成以来,已经有近百种具有0-D犤3,4犦,1-D犤5,6犦,2-D犤7~9犦,3-D犤10~13犦结构的磷酸锌被成功地合成出来。其中令人瞩目的是具有螺旋孔道的手性磷酸锌犤14犦以及具有二十四元环孔道的两种微孔磷酸锌化合物犤15,16犦的合成。这些化合物大多是采用水热技术以有…  相似文献   

14.
The crystal and molecular structure of bis(tetra­methyl­ammonium) di­chloro­tetra‐μ2‐methoxo‐di‐μ2‐oxo‐octo­oxo­tetra­molybdate(VI), (C4H12N)2[Mo4O10(OCH3)4Cl2], has been determined from X‐ray diffraction data. The crystallographically centrosymmetric anion is built up of four edge‐sharing octahedra, two MoO6 and two MoO5Cl.  相似文献   

15.
Doubly charged lead monohydrate, [Pb(H2O)]2+, was predicted to be unstable in the gas phase, but it has recently been observed to form in low yield via ligand change between [Pb(CH3CN)]2+ and H2O [Shi, T.; Orlova, G.; Guo, J.; Bohme, D. K.; Hopkinson, A. C.; Siu, K. W. M. J. Am. Chem. Soc. 2004, 126, 7975-7980]. Here we report that abundant [Pb(H2O)]2+ is formed in the gas phase by ligand-exchange reaction between [Pb(N2)n]2+ (n = 1-3) and water after collisional activation. Density functional theory has been used to examine the ligand-exchange reaction profile. A comparison of the potential-energy surfaces between [Pb(N2)]2+ and [Pb(CH3CN)]2+ reacting with H2O provides strong evidence that the ligand-exchange reaction of [Pb(N2)]2+ with H2O to form [Pb(H2O)]2+ is more efficient than that of [Pb(CH3CN)]2+ with H2O.  相似文献   

16.
The pH-dependent self-condensation of the [Mo 2 S 2 O 2 ] 2+ complex fragment gives the wheellike Mo12 cluster depicted on the right (ball-and-stick model; large balls: S, medium balls: O, small balls: Mo). Applying this synthetic strategy to other starting materials could provide access to other polyoxothiometalates with well-defined cavities.  相似文献   

17.
运用密度泛函理论(DFT)的BP86方法, 对[M6Om(C25N4H18)n]2-(M=W, Mo; n=1, 2; m=17,18)进行了几何结构优化, 其中Mo系列结构化合物优化的几何结构与实验值吻合较好. 在净电场为零的条件下, 运用DFT/LB94方法计算了体系的二阶非线性光学系数β值: 体系1和2的βvec值分别为154.4×10-30和124.8×10-30 esu. 表明它们具有较大的二阶非线性光学系数, 且Mo系列比W系列的β值大. 而体系3和4的βvec值分别为218.0×10-30和191.8×10-30 esu. 体系3和4的βvec值分别比体系1和2的大, 表明增加给体的数目有利于提高NLO响应, 但都小于它们的2倍.  相似文献   

18.
Molybdenum(II) Halide Clusters with six Alcoholate Ligands: (C18H36N2O6Na)2[Mo6Cl8(OCH3)6] · 6CH3OH and (C18H36N2O6Na)2[Mo6Cl8(OC6H5)6] . The reaction of Na2[Mo6Cl8(OCH3)6] and 2,2,2-crypt yields (C18H36N2O6Na)2[Mo6Cl8(OCH3)6] · 6 CH3OH ( 1 ), which is converted to (C18H36N2O6Na)2[Mo6Cl8(OC6H5)6] ( 2 ) by metathesis with phenol. According to single crystal structure determinations ( 1 : P3 1c, a=14.613(3) Å, c=21.036(8) Å; 2 : P3 1c, a=15.624(1) Å, c=19.671(2) Å) the compounds contain anionic clusters [Mo6Cl8i(ORa)6]2? ( 1 : d(Mo—Mo) 2.608(1) Å to 2.611(1) Å, d(Mo—Cl) 2.489(1) Å to 2.503(1) Å, d(Mo—O) 2.046(4) Å; 2 : d(Mo—Mo) 2.602(3) Å to 2.608(3) Å, d(Mo—Cl) 2.471(5) Å to 2.4992(5) Å, d(Mo—O) 2.091(14) Å). Electronic interactions of the halide cluster and the phenolate ligands in [Mo6Cl8(OC6H5)6]2? is investigated by means of UV/VIS spectroscopy and EHMO calculations.  相似文献   

19.
Molybdenum(II) Halide Clusters with two Alcoholate Ligands: Syntheses and Crystal Structures of (C18H36N2O6Na)2[Mo6Cl12(OCH3)2] and (C18H36N2O6Na)2[Mo6Cl12(OC15H11)2] · 2C4H6O3 . Reaction of Mo6Cl12 with two equivalents of sodium methoxide in the presence of 2,2,2-crypt yields (C18H36N2O6Na)2[Mo6Cl12(OCH3)2] ( 1 ), which can be converted to (C18H36N2O6Na)2[Mo6Cl12(OC15H11)2] · 2C4H6O3 ( 2 ) by metathesis with 9-Anthracenemethanole in propylene carbonate. As confirmed by X-ray single crystal structure determination ( 1 : C2/m, a=25.513(8) Å, b=13.001(3) Å, c=10.128(3) Å, β=100.204(12)°; : C2/c, a=15.580(5) Å, b=22.337(5) Å, c=27.143(8) Å, β=98.756(10)°) the compounds contain anionic cluster units [Mo6ClCl(ORa)2]2? with two alcoholate ligands in terminal trans positions ( 1 : d(Mo—Mo) 2.597(2) Å to 2.610(2) Å, d(Mo—Cli) 2.471(3) Å to 2.493(4) Å, d(Mo—Cla) 2.417(8) Å and 2.427(8) Å, d(Mo—O) 2.006(13) Å; 2 : d(Mo—Mo) 2.599(3) Å to 2.628(3), d(Mo—Cli) 2.468(8) Å to 2.506(7) Å, d(Mo—Cla) 2.444(8) Å and 2.445(7) Å, d(Mo—O) 2.012(19) Å).  相似文献   

20.
The title dodecanuclear Mn complex, namely dodeca‐μ2‐acetato‐κ24O:O′‐tetraaquatetra‐μ2‐nitrato‐κ8O:O′‐tetra‐μ4‐oxido‐octa‐μ3‐oxido‐tetramanganese(IV)octamanganese(III) nitromethane tetrasolvate, [Mn12(CH3COO)12(NO3)4O12(H2O)4]·4CH3NO2, was synthesized by the reaction of Mn2+ and Ce4+ sources in nitromethane with an excess of acetic acid. This compound is distinct from the previously known single‐molecule magnet [Mn12O12(O2CMe)16(H2O)4], synthesized by Lis [Acta Cryst. (1980), B 36 , 2042–2044]. It is the first Mn12‐type molecule containing nitrate ligands to be directly synthesized without the use of a preformed cluster. Additionally, this molecule is distinct from all other known Mn12 complexes due to intermolecular hydrogen bonds between the nitrate and water ligands, which give rise to a three‐dimensional network. The complex is compared to other known Mn12 molecules in terms of its structural parameters and symmetry.  相似文献   

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