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1.
1INTRODUCTION The construction of metal-organic coordination polymers based on covalent interactions[1]or supra-molecular contacts such as hydrogen-bonding and/orπ-πinteractions)[2]is now of great interest not only due to the enormous variety of intriguing structural topologies themselves,but also to their unexpected physical and chemical properties for potential prac-tical applications as functional materials.Many N-containing ligands,such as4,4?-bipyridine,2,2?-bi-pyridine and1,10-phen…  相似文献   

2.
1 INTRODUCTION In recent years, the design and synthesis of metalorganic coordination polymers have attracted considerable attention, for such supramolecular assemblies have interesting structures as well as potentiaapplications as smart optoelectronic, magnetic andporous materials. By judicious selection of ligandand metal coordination geometries, control over thetopology and geometry of the infinite networks canbe gained. As neutral donor ligands, 4,4?-bpy, pyrazine and imidazole which …  相似文献   

3.
1 INTRODUCTION It is well known that the bi-functional 4,4?-bi- pyridine (4,4?-bpy) has the ability to act as a rigid, rod-like organic building block in the self-assembly of coordination frameworks. Many researches have also been done on the metal oxalate compounds. The remarkable coordination abilities of oxalate and 4,4?- bpy ligands are applied to design and synthesize new polymeric coordination complexes[1~4] containing mixed bridging ligands. Manganese is one of the several first-r…  相似文献   

4.
The one-pot hydrothermal reaction of CuCl2 with H2CPOA and 4,4'-bpy results in two new coordination polymers, [Cu(CPOA)(4,4'-bpy)(H2O)2]·1.5H2O (1) and [Cu2(HCPOA)4(4,4'-bpy)4] (2) (H2CPOA=4-carboxyphenoxy acetic acid, 4,4'-bpy=4,4'-bipyridine) since CPOA^2- anions reach equilibrium with HCPOA^- anions in the reaction system. The crystal structure of 1 shows a triple interpenetration CdSO4-like net with 1D channel, in which lattice water molecules are located. Complex 2 is a ladder-like 1D double chain structure assembled through coordination bonds and O—H…N hydrogen bonds.  相似文献   

5.
1 INTRODUCTION During the past few years, many one-, two- and three-dimensional coordination polymers have been generated from transition metal templates with rigid and flexible pyridyl-containing bidentate or multidentate spacers[1, 2]. Although in the past few years, increasing interest has been given to the coordination polymer of 4, 4?azobispyridine[3, 4] and some 3, 3?azobispyridine complexes[5, 6] were repor- ted three decades ago, no crystal structure of 3, 3?azpy complex has been…  相似文献   

6.
1INTRODUCTION Recently,cyano-bridged lanthanide-transition me-tal complexes have been extensively investigateddue to their potential applications as precursors in the preparation of rare earth orthoferrites,fluores-cent and magnetic materials[1].Various complexes of this system have been obtained in order to ex-plore the relations between structures and pro-perties by using different ligands,such as DMF,4,4?-bipy,and so on,to fill the coordination sites of lanthanide ions[2~9].But up to…  相似文献   

7.
1 INTRODUCTION Metal-organic coordination polymer has particu- lar and special structure characters with some caves, holes and channels[1], and can be used in selected catalysis, molecular recognition, reversible exchan- ge of host-guest molecules (ions), super purity sepa- ration, biological conductor[2~5], etc. In the past ten years, polymers with bridging ligand have been widely investigated[6, 7]. The development of supra- molecular architectures of inorganic-organic hybrid molecules …  相似文献   

8.
1 INTRODUCTION Multinuclear coordination compounds have attrac-ted much attention due to their distinctive optical, elec-tric and magnetic properties as well as enzyme ana-logue[1~4]. It is important for carboxylic acid to de-sign this compound[5~8]. EDTA is a useful titrant formetal determination because EDTA molecule is easyto coordinate with a metal atom (1:1). Other types ofEDTA-M compounds are seldom to know except Ln2-M3(EDTA)3(H2O)11?12H2O[5] and (UO2 )2EDTA[9]. …  相似文献   

9.
1 INTRODUCTION Recently construction of new coordination poly-mer networks through the rational combination oforganic ligands ‘spacers’and metal ‘nodes’ is an areaof intense interest[1~3] because of their capability ofshowing novel magnetic[4], nonl  相似文献   

10.
1 INTRODUCTION Chemistry of manganese cluster has become an attractive research field because of the involvement of manganese in several biological redox-active sys- tems[1,2], especially in the oxygen-evolving complex (OEC) of photosystem Ⅱ (PSⅡ) in green plants[3]. It was thought that the coordination environment of Mn in OEC contains O and N donors, and the bind- ing of aqua to the Mn site may be important to the oxidation of aqua for the evolution of dioxygen[4, 5]. In recent …  相似文献   

11.
Hydrothermal reactions of three aromatic polycarboxylic acids and the transitional metal cations in the presence of phen and 1,4-bib afford three new coordination polymers: [Cd2(bpp)1.5(Hbpp)(phen)2]n(1), [Mn3(Htptc)2(phen)2(H2O)2]n(2), and {[Cu(btc)0.5(1,4- bib)]·2H2O}n(3)(H2bpp = 2,6-bis(4'-carboxyphenyl)-4-phenylpyridine, H4tptc = terphenyl-2,5,2',5'-tetracarboxylic acid, H4btc = biphenyl-2,2',4,4'-tetracarboxylic acid, phen = 1,10-phenanthroline, and 1,4-bib = 1,4-bis(1H-imidazol-1-yl)benzene). Their structures have been determined by singlecrystal X-ray diffraction analyses, elemental analyses, IR spectra, and powder X-ray diffraction(PXRD) analyses. In compound 1, the CdII cations are linked by bpp2- to form one ladder structure, based on which a 3D network is constructed with the help of non-covalent interactions. The topology of 2 is a 3D(3,4,5)-connected framework with the Point Schl?fli symbol of(42.6)32(4.62.8)(45.64.8)2. Compound 3 shows an unprecedented 3D(4,4)-connected framework with the Point Schl?fli symbol of(64.82)2(65.8). Moreover, the luminescent property of 1 has been investigated.  相似文献   

12.
1 INTRODUCTION For a long time much research interest has been focused on coordination polymeric compounds[1] because these new coordination polymers may afford new materials with useful properties, such as catalytic activity, micro-porosity, electrical conduc- tivity, non-linear optical activity, magnetic coupling behavior and so on[2]. Thiocyanate anion is a very useful bridging ligand, and many complexes[3~5] are synthesized with it as bridging ligand and some of them exhibit interesti…  相似文献   

13.
1 INTRODUCTION The controlled assembly of inorganic and coordination polymers from simple building blocks is an important challenge in the design of high- dimensionality systems. In the crystal engineering 'toolbox'[1], hydrogen bonding moieties are perhaps the implements used the most in the design of such supramolecular systems[2], and have been particularly strongly applied towards the synthesis of molecular magnetic materials[3~6]. Copper complexes play an important role in catalyzin…  相似文献   

14.
1 INTRODUCTION The increasing interest in inorganic-organic hybrid framework assemblies has resulted in a great number of research efforts focused on the develop- ment of new functional materials possessing various potential applications on catalysis, electrical conduc- tivity and magnetism[1~4]. In recent years, the inter- action of H2pdc with several metal ions has been extensively studied[5, 6] due to its unique ability to form stable chelates in diverse coordination modes such as bid…  相似文献   

15.
Three new inorganic-organic composite polyoxotungstates [Cu(2,2'-bpy)2]5[α-PW11.5Cu0.5O40]·2H2O 1, [Co(2,2'-bpy)2(N3)2]4H3[α-PW12O40]·3H2O 2 and [Cu(2,2'-bpy)2(4,4'-bpy)]2[α-GeW12O40]-4H2O 3 (2,2'-bpy = 2,2'-bipyridine, 4,4'-bpy = 4,4'-bipyridine) have been hydrothermally synthesized and structurally characterized. 1 crystallizes in the orthorhombic space group Pna21 with a = 27.847(3), b = 21.597(2), c = 20.1179(19)A, V= 12099(2)A^3, Z= 4, GOF= 1.038, R = 0.0427 and wR = 0.1035; 2 belongs to the triclinic space group P1^- with a = 12.31150(10), b = 16.1954(4), c = 19.36290(10)A, α = 99.366(11), β =105.168(8), γ = 111.836(8)°, V = 3309.98(9)A3, Z = l, GOF = 1.024, R = 0.0739 and wR = 0.2216; and 3 crystallizes in the monoclinic space group P21/n with a = 12.858(4), b = 20.943(6), c = 15.598(5)A, β = 102.338(5)°, V= 4103(2)A3, Z = 2, GOF = 1.026, R = 0.0557 and wR = 0.1316. The common structural features of 1-3 are that their molecular structures all consist of a saturated a-Keggin polyoxoanion and several discrete metal-organic moieties. Intriguingly, 2 and 3 are composed of metal-organic coordination moieties with two mixed ligands.  相似文献   

16.
People have long been interested in the coordination polymers of terbium! with carboxylic acids for those polymers often have peculiar structure and luminescent feature. They can be used as extraction and separation agents, bactericides, luminescent and functional materials. For example, they are used in the production of plastic membranes, lighting materials, developing materials and ornament materials[1~3]. In chemical literature, we can find many research reports about ternary complexes of…  相似文献   

17.
1 INTRODUCTION Recently, the design and synthesis of novel inorg-anicorganic supramolecular complexes have been at-tached more and more attention due to their poten-tial applications in many areas[1~3]. Copper complex-es have attracted much attention owing to their intri-guing properties, such as molecular magnetization,absorption, heterogeneous catalysis, etc[4, . A series5]of copper-carboxylate complexes have been reportedand all kinds of coordination models of the car-boxylic group a…  相似文献   

18.
Polyoxometalates may be versatile inorganic building blocks for the construction of molecular-based materials. By means of their multiple coordination requirements and oxophilicity, lanthanide cations are suitable to link polyoxometalate building blocks to form new classes of materials with potentially useful magnetic and luminescent properties1-4. Peacock and Weakley studied the interactions between the [α-SiW11 O39]8? isomer and lanthanide cations5, and they reported that the [α-SiW11O39…  相似文献   

19.
1 INTRODUCTION In the last decade, cyano-bridged Prussian Blueanalogues[1] have been intensively studied from theviewpoint of application as functionalized molecule-based magnets[2], chemical sensor materials[3], fluo-rescent materials[4] and zeolitic-type materials[5, , 6]etc. In 1976, a series of cyano-bridged three-dimen-sional rare earth hexacyanometalates(IIILnM(CN)6?nH2O (M = Fe or Cr, n = 4 or 5) were crystallized andsubjected to single-crystal X-ray analysis[7]. …  相似文献   

20.
1 INTRODUCTION Molecular structures of metallic complex and intermolecular weak interaction mode have become the focal fields of crystal engineering and supra- molecular chemistry. As we all known, intermole- cular weak interactions include hydrogen bonds[1, 2], π-π staking interaction[3, 4], metal-metal weak inte- raction[5, 6] and chelate-ring-chelate-ring weak inte- raction, et al.[7] Binary, ternary and quaternary car- boxylic acid ligands possess versatile coordination modes with me…  相似文献   

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