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1.
Two new 3D heterometallic (3d-4f) coordination polymers {[Ln2Cu(pydc)4(H2O)6]·2H2O}n [Ln = Eu (1) and Gd (2)] have been synthesized by hydrothermal reactions and characterized by elemental analysis, X-ray single-crystal analyses, and IR spectroscopy. X-ray crystal structure analyses show that 1 and 2 possess 3D networks and strong intramolecular hydrogen bonding interactions which was confirmed by thermogravimetric (TG) analysis.  相似文献   

2.
Three new complexes, [Zn(dtb)(4,4′-bipy)]·5H2O (1), [Zn(dtb)(bpp)]·H2O (2) and [Zn(dtb)(phen)2]·CH3- CH2OH·H2O (3) (dtb = 5,5′-dithiobis(2-nitrobenzoic acid), 4,4′-bipy = 4,4′-bipyridine, bpp = 1,3-bi(4-pyridyl) propane, phen = 1,10-phenanthroline), have been constructed by dtb ligand and zinc salt in the presence of different assistant N-containing ligands under hydrothermal conditions. The structures of the complexes were established by single-crystal X-ray diffraction analysis. Although compounds 1 and 2 are both 2D networks, the cavities' forms and pitch of helix are different. The structure of compound 3 shows a 1D helical chain, and is extended by the supermolecule interactions into a 2D framework. These neutral polymeric complexes exhibit structural and dimensional diversity due to the different coordination modes of the flexible dtb ligand and the effect of assistant ligands.  相似文献   

3.
Hydrothermal reactions of oxalic acid(H2ox) and 2-sulfobenzoic acid(H2L) with lanthanide oxide or hydroxide yielded five lanthanide oxalatosulfocarboxylates.They have a general formula [Ln2L2(ox)(H2O)6]n[Ln = La(1),Nd(2),Eu(3),Gd(4),Tb(5)].Their structures were characterized by single crystal X-ray diffraction,powder X-ray diffraction(PXRD),infrared(IR) spectroscopy,elemental analysis(EA),and thermogravimetric analysis(TGA).1-5 are isostructural coordination polymers and feature one-dimensional(1D) chains,which are extended into 3D supramolecular frameworks through inter-chain hydrogen bonds between coordinated H2O donors and oxygen acceptors from carboxylate,sulfonate and oxalate groups.In addition,the solid-state photoluminescence properties of the Nd(2),Eu(3) and Tb(5) derivatives have been measured at room temperature.The Eu and Tb-containing coordination polymers(CPs) exhibit intense red and green luminescence emissions,respectively,with lifetimes in the order of millisecond.  相似文献   

4.
The lanthanide coordination polymers bearing a 13-membered macrocycle, [(13-EDTA-pnOH)H2] were synthesized. The products [Ln(13-EDTA-pnOH)(H2O)2·NO3]n (Ln = Eu(1), Tb(2), Dy(3)) have been obtained by MS, IR and element analyses. The solid-state structure of 1 was established by single-crystal X-ray analysis. The coordination geometry around the central metal atom in complex 1 is a nine-coor-dinated, tricapped-trigonal prism having six donor atoms (two amine nitrogen atoms, two amide oxygen atoms and two carboxymethyl oxygen atoms) from one ligand, one oxygen atom from a neighboring ligand, and two more oxygen atoms from two water molecules. The europium atoms are linked by―Eu―O―C―O―Eu―bridges to form an infinite chain.  相似文献   

5.
The hydrothermal synthesis and crystal structures of four coordination polymers, namely, 2D [Zn(μ3-ta)(pytaH)]n (1), 2D [Zn(μ3-pyta)Cl]n (2), 1D [Cd(μ-pyta)2(H2O)]n (3), and 3D [Cd(μ3-pyta)(μ-Cl)]n (4) (pyta = (4-pyridylthio)acetate, ta = thioglycolate), are reported. They are based on (4-pyridylthio)acetate and its derived ligand. The ta^2- ligand present in 1 was generated from an in situ C(sp^2)-S bond cleavage of the pyta ligand. In these compounds, versatile intermolecular interactions, such as close S…S interactions and strong (O-H…O/N/S) or weak (C-H…O/S, C-H…Cl) hydrogen bonding interactions, play an important role in the formation of three-dimensional supramolecular networks in the solid state.  相似文献   

6.
A series of inorganic-organic hybrids K2Na m H9−m [{Ln(GeW11O39)2}{Cu2(bpy)2(μ-ox)}]·nH2O (bpy = 2,2-bipyridine and ox = oxalate; Ln = La, Nd, Sm, Eu, Gd; n = 19, 17, 22, 20, 19; m = 4, 4, 4, 9, 2) were isolated after reacting in a potassium acetate buffer. X-ray structural analyses show that compounds 1–5 are isomorphic and consist of [Ln(GeW11O39)2]13− polyoxoanion building blocks and oxalate-bridged dinuclear copper metalorganic complex with a 1D chain structure. The 1D chain further connects into the 3D framework by π-π interactions with neighboring bpy groups. The magnetic susceptibility data indicate that antiferromagnetic coupling between the neighboring Cu2+ ions in the structure and the rare earth ions affects magnetic property of the structure.  相似文献   

7.
Two Mn(Ⅱ) coordination supramolecules, [Mn2(C8HTO2)4(phen)2(p-H20)] (1) and [Mn2(btec)(phen)2(H2O)6]·2H2O (2) (phen=1,10-phenanthroline, H4btec=1,2,4,5-benzenetetracarboxylic acid), were synthesized by hydrothermal method. The crystal structures of the complexes were determined by X-ray single crystal diffraction. The result indicates that (1) and (2) are both binuclear Mn(Ⅱ) complexes. The existence of hydrogen bonds makes the binuclear complexes become further connected to coordination supramolecules, which possess 1D and 3D infinite structures respectively. The complexes were identified by IR, UV-Vis, surface photovoltage spectrum (SPS) and field-induced surface photovoltage spectrum (FISPS). The results of SPS for the complexes indicate that they both exhibit positive surface photovoltage response bands in the range of 300-600 nm. The SPS phase spectrum and FISPS of complexes indicate that they show certain p-type semiconductor characteristic. However, the intensity, position and number of the SPV response bands are different obviously. The difference of the SPV response bands is mainly attributed to the different structures of the complexes and the different coordination environment of Mn(ll) in the two complexes. This paper discusses the action of hydrogen bonds in the construction of the supramolecule and the change on the surface photovoltage of complex in different coordination environment.  相似文献   

8.
0 IntroductionThegreatattentionhasbeenpaidtorareearthorradioactiverareearthmetalcomplexesfortheirvariousbiologicactivi ties[1 3] .Forexamples,theradioactiverareearthmetal1 53SmⅢ com plexeswerewidelyusedfortumourtherapyofbrain ,liver,lung ,heartandbonetissues[4 5] ;forrareearthmetalEuⅢandTbⅢemitinguniquefluorescence ,theircompoundswereappliedfordiagnosesofvariousdiseases[6 ,7] ;forrareearthmetalGdⅢcontainingthemosthigh spinsingleelectrons,itscomplexeswereusuallyusedforcontrastagentsofmag…  相似文献   

9.
The synthesis and characterization of dimeric rare-earth amides stabilized by a dianionic N-aryloxo functionalized ,8-ketoiminate ligand are described. Reactions of 4-(2-hydroxy-5-methyl-phenyl) imino-2-pentanone (LH2) with Ln[N(SiMe3)2]3(μ-Cl)Li(THF)3 in a 1:1 molar ratio in THF gave the dimeric rare-earth amido complexes [LLn{N(SiMe3)2}(THF)]2 [Ln = Nd (1), Sm (2), Yb (3), Y (4)]. These complexes were well characterized, and the definitive molecular structures of complexes 3 and 4 were determined. It was found that complexes 1-4 can initiate the ring-opening polymerization of ε-caprolactone, and the ionic radii of the central metals have significant effect on the catalytic activity.  相似文献   

10.
Three new mixed-ligand Fe(II/III) complexes [Fe22–btec)(μ2–H2btec)(phen)2(H2O)2]n (1), [Fe2(btec) (phen)2(H2O)4] (2), and {[Fe(o-pha)(phen)(H2O)]•H2O}n (3) (phen=1,10-phenanthroline, o-H2pha=o-phthalic acid, H4btec=1,2,4,5-benzenetetracarboxylic acid) have been hydrothermally synthesized and detected by single crystal X-ray diffraction, showing that complexes (1) and (2) are both bridged by the betc4− ligands to form 1D chain and dinuclear structure and complex (3) is bridged by the o-pha groups to form 1D chain structure. The coordinated modes of the carboxyl groups adopt μ21η1ηη1η1 and μ22η1 respectively in com-plexes (2) and (3). The betc groups in complex (1) show two different coordinated modes: μ21η1η1η1 and μ21η1. In addition, the hydrogen bonds and π…π type interactions make the complex molecule further connect to three-dimensional and two-dimensional networks respectively. These complexes are detected by IR, UV-Vis-NIR and surface photovoltage spectrum (SPS). The SPS of complexes (1)–(3) indicate that there are positive SPV responses in the range of 300–600 nm and show p-type semiconductor characteristic. Because the structure, the valence and the coordinative environment of the Fe ions are all different in the three complexes, the intensity, position and the number of the response bands are different obviously. The results of SPS are corresponding with UV-Vis-NIR spectra.  相似文献   

11.
Song  Jirong  Chen  Zhaoxu  Xiao  Heming  Hu  Rongzu  Li  Fuping 《科学通报(英文版)》1999,44(3):214-218
[Li(NTO)(H2O)2] was prepared by mixing the aqueous solution of 3-nitro-1,2,4-triazol-5-one (NTO) and lithium hydroxide. The crystal structure of [Li(NTO)(H2O)2] was determined by single crystal diffraction analysis. The crystal is monoclinic, space group P21/n with crystal parameters of a = 0.742 0(2) nm, b = 0.344 9(1) nm,c = 2.490 6(3) nm, β= 94.89(1)°, Z = 4,D c , = 1.799 g cm−3,V = 0.635 nm3, μ = 1.591 cm−1, F(000) = 392. The finalR is 0.051. The MNDO MO calculation shows that the coordinate bonds of title compound possess certain extent of covalent character. O2 atom of NTO anion is bonded to Li atom; the nitro group will be lost first when NTO is decomposed.  相似文献   

12.
Using two structurally related benzoates bearing different H-bond acceptors as co-ligands, three new azido-Cu^Ⅱ compounds, [Cu(L^1)(N3)(H2O)]n(1), [Cu(L^1)(N3)(MeOH)]n (2), and [CuL^2HL^2(N3)3(H2O)]n(3) (HL^1 = 4-nitrobenzoic acid; HL^2= 2-phenyl-4-quinolinecarboxylic acid), have been synthesized and structurally characterized. 1 is a carboxylate/EO-azido bridged copper chain, forming 3D structure by H-bonds, and 2 has a similar chain structure as 1 but forming a 2D structure by H-bonds, while 3 is a 3D supramolecular network with ternary center H-bonds. Magnetic study indicates that domain ferromagnetic coupling interactions were found to exist in complexes 1 and 3.  相似文献   

13.
The biomimetic synthesis and the study of the ca-talysis mechanism of molybdenum and tungsten oxotransfer enzyme have been attracted considerable at-tention for a long time, because the oxotransfer enzymes play an important part in the nitrogen, sulfur and carbon cycles in the biological system[1—4]. With the development of the X-ray crystallography, it is possible to determine the structure of molybdenum and tungsten enzymes. However, due to the complexity and dedicated nature of the protein…  相似文献   

14.
利用钌金属络合物离子和芳香有机二羧酸配体与铀酰离子在水热条件下反应,合成了一例新的异金属有机配位聚合物,也即[Ru(bipy)3][(UO2)2(BDC)3]·2H2O,利用单晶X-射线衍射方法、粉末X-射线衍射方法、红外光谱对该配位聚合物结构进行了基本表征。该配合物是由金属配合物阳离子客体[Ru(bipy)3]2+ 、二维蜂窝状平面结构的聚阴离子主体框架[(UO2)2(BDC)3]n2-之间通过分子内和分子间C-H···O氢键的相互作用形成准三维超分子结构。此外,固体紫外-可见漫反射光谱测试表明此配合物具有半导体性质,是潜在的光电材料。固体荧光测量表明配合物表现出强烈的发光性能。  相似文献   

15.
A series of sandwich-type tungstoarsenates heteropoly compounds with As/W ratio of 4/30, Na16[As4W30M4(H2O)2O112]·XH2O (M = Zn,Cu,Co,Ni,Mn and Cd), have been synthesized for the first time and structurally characterized by elemental analysis, IR and 183W NMR spectra. The crystal structure of Na16[As4W30Cu4(H2O)2O112]·63H2O was determined to be a triclinic system, of P1 symmetry, a = 1.2721(3) nm, b = 2.451 6(5) nm, c = 2.6450(5) nm, α= 89.90(3)°,β= 77.32(3)°, γ= 89.96(3)°, 2=2. Using tetrahepty lammonium bromide as a phase transfer reagent, [As4W30Cu4(H2O)2O112]16- was transferred from aqueous solution to organic phase (benzene), and the heteropolyanion lost the coordination water molecules to form the coordination-unsaturated ion. After lactic acid was added to the benzene solution, the coordination-saturation was recovered. By esterification reaction between lactic acid and cholesterin, the latter was attached to the heteropolyanion indirectly. Therefore, a new type of lyotropic liquid crystal was obtained, which was characterized by a polarimicroscope, DSC and variable temperature wide-angle X-ray diffraction.  相似文献   

16.
Magnetic properties of heteropolyoxometalates   总被引:1,自引:0,他引:1  
The progress of the study on the magnetic properties of heteropolyoxometalates during the late decade is reviewed. Some anions of heteropolyoxometalates containing magnetic atoms, such as [M4(H2O)4(PW9O34)2]10- and[M4(H2O)4(P2W15O56)2]16-[M = Co(Ⅱ), Zn( Ⅱ ), Cu( Ⅱ ), Mn(Ⅱ ), Ni(Ⅱ)], and [GaW9O37M3(H2O)3]n-[M = Fe(Ⅲ), Cu(Ⅱ), Co(Ⅱ)] showed ferromagnetic and antiferromagnetic properties. The combination of heteropoly anions and organic π-donor of TTF+ (te-trathiofulvalene cation) results in a variety of magnetic properties. Furthermore, there is an interaction between the inorganic and organic components. The electrocrystallization technique can prepare the organic-inorganic salts of this kind, which will become the new member of molecular magnetic materials. Heteropoly blue is a kind of the mixed-valence complexes and its reduction electrons can be delocalized over anionic framework. The further study on the magnetic properties of heteropolyoxometalates will provide important information for the design of molecular materials.  相似文献   

17.
文中通过溶剂热法合成配位聚合物[CuII(bpdc) (H2O)2]n和 [Ag4I(bpdc) (H2bpdc)(Hbpdc)2]n(bpdc=2, 2'-联吡啶-3,3'-二羧酸根)的合成反应, 对影响溶剂热反应的主要因素,如反应物摩尔比、反应物浓度、pH值、溶剂种类进行系统研究, 揭示溶剂热反应的经验规律.  相似文献   

18.
Lanthanide methoxides supported by carbon-bridged bis(phenolate) ligands 2,2′-methylene-bis(6-tert- butyl-4-methylphenoxo) (MBMP2-) [(MBMP)Ln( μ-OMe)(THF)2]2 (Ln = Nd (1), Yb (2)) were synthesized in high yields by the protolysis reaction using (C5H5)3Ln(THF) as starting materials, and complex 1 was structurally characterized. The coordination geometry around the center metal can be best described as a distorted octahedron. Complexes 1 and 2 were shown to be efficient initiators for the ring-opening polymerization of 2,2-dimethyltrimethylene carbonate (DTC) and L-lactide. The mechanism of DTC polymerization was explored by the end group analysis of the oligomer.  相似文献   

19.
Early transition metal catalysts containing twophenoxy-imine ligands, called FI catalysts which havevery high potential to become a new generation of olefinpolymerization catalysts, are new-type catalysts whichhave attracted much attention in recent years[1—3]. Many ofthem display activities comparable to those of the metal-locene catalysts and, in some cases, behave as living po-lymerization catalysts of α-olefins. Brookhart and Gibsonet al.[4,5] recently reported separately series of Schi…  相似文献   

20.
A new 3-D porous Gd-Cu heterometallic polymer [Gd2Cu3(bpy)2- (ip)6]·6H2O (1) (bpy = 2,2′-bipyridine, H2ip = isophthalic acid) has been hydrothermally synthesized and structurally characterized. Compound 1 crystallizes in the triclinic space group P1and displays a 3-D non-interpenetrated α-Po net- work with 1-D channels filled transversely by the hexa-nuclear chain-like (H2O)6. The EPR and thermal stability of 1 were investigated.  相似文献   

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