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1.
1 INTRODUCTION Organic-inorganic hybrid materials and polyoxo-metalates have received much attention because of their intriguing structural diversity and potential applications in molecular adsorption, ion exchange, heterogeneous catalysis and nanotech nology as well as in electrical, magnetic and photochemical areas[1, 2]. One of the important ad- vances in the design of new organic-inorganic hybrid materials is utilizing poly- oxometalates’ coordination ability to produce poly- oxoanio…  相似文献   

2.
1 INTRODUCTION The design synthesis of metal oxide heterpoly compounds have been the subject due to their diverse structures and potential applications in catalysis, sorption, electrical conductivity, ion exchange and anti-virus[1]. Molybdenum phosphates with microporous framework serve as a new kind of inorganic microporous materials. In the course of our investigation on the synthesis of Molybdenum phosphates, we have hydrothermally synthesized an organically templated solid material[…  相似文献   

3.
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   

4.
<正> (NH4)11[Na(H2O)2P4W14O58)·12H2O, Mr = 4099. 39, triclinic, space group P1, a = 14. 376(2), b = 19.861(9), c=13. 010(3)(?) , α=104. 68(2), β=91. 37(1), γ= 104. 05(2)°, V = 3471. 1 (?)3, Z = 2, Dc=3. 922g/cm3, μ (MoKα) = 238. 274cm-1, F(000) = 3664, R = 0.0510, Rw = 0. 0665 for 9260 observed reflections with I> 3σ(I). The polyanion [Na(H2O)2P4W14O58]11- consists of two PW7O29 subunits anisostructurally, two linkage phosphorous atoms and one sodium ion with two water ligands as well. The geometries of tungsten atoms within these two subunits are almost the same as those in K12P4W14O58· 21H2O[2]. The four phosphorous atoms are in PO4 coordinations. The sodium ion locates nearly at the center of the polyanion, and is coordinated by two water molecules, five oxygen atoms of the anion and one phosphorous atom with Na-P = 3. 053(3) (?). Due to the presence of the sodium atom, the interactions between oxygen and tungsten atoms in the polyanion are somewhat weakened.  相似文献   

5.
1INTRODUCTION There is currently considerable interest in the ra-tional design and controlled synthesis of metal-organic frameworks(MOFs)with unique structural motif on account of their promising applications as catalysts,gas storage,selective separation,sensor,ion exchange and magnetic materials[1,2].Particu-larly,the supramolecular architectures with helical structures have received much more attention over the past decades owing to their specific functions in biology.It is well recogn…  相似文献   

6.
A new dinuclear centrosymmetric complex [LaL(HL)(H2O)3]2·2H2O (H2L = 3-nitro- phthalic acid, NPA) was synthesized in water/ethanol solution and characterized by X-ray diffraction, IR spectrum and TGA-DTA. The complex crystallizes in triclinic system, space group P1 with a = 8.1549(16), b = 8.8856(18), c = 15.277(3) , α = 100.93(3), β = 90.81(3), γ = 104.56(3)°, V = 1049.8(4) 3, Z = 1, μ = 2.125 mm-1, Dc = 1.994 g/cm3, R = 0.0259 and wR = 0.0679. Two 3-nitrophthalates(2-) coordinate with the La3+ ions in a bridging mode, and two monohydrogen- 3-nitrophthates(1-) and three waters in terminal ways, respectively. Each La3+ ion is nine- coordinated to exhibit a distorted tricapped trigonal prism coordination polyhedron. Both the coordinated and crystal waters are involved in the inter- and intramolecular hydrogen bonds. The dinuclear units are linked into a 2D network structure in the ab plane via intermolecular hydrogen bonds along the axes a and b. Two crystal waters fill each rhombic pore of the network. The networks are further packed along the c axis forming a layered supramolecular structure through the C–H…O weak forces between the adjacent sheets. TGA analysis shows the complex undergoes the loss of waters of crystallization and coordination and the decomposition of ligands sequentially.  相似文献   

7.
1 INTRODUCTION Since Bedard et al. reported microporous tin(IV) sulfides synthesized by hydrothermal method in the presence of organic amine in 1989[1, 2], a number of thiostannates have been synthesized using hydro- or solvothermal techniques with organic amines as tem- plates. The structures of the resulting tin(IV) sulfi- des are related to the types of organic amines. Two- dimensional polyanions of the types of [Sn3S7]2- and [Sn4S9]2-, which are denoted as SnS-1 and SnS-3, respe…  相似文献   

8.
A novel one-dimensional manganese(Ⅱ) complex containing nitronyl nitroxide radical [Mn2(IM2-py)2(Ac)2((μ1.1-N3)(μ1,3-N3) . EtOH]n was synthesized and characterized structurally and magnetically. It crystallizes in the monoclinic space group p21/n. Each Mn(Ⅱ) ion is six-coordinated in a distorted octahedral environment. The two N atoms of the nitronyl nitroxide radical and the two O atoms of acetate ligands are in the equatorial plane, whereas the two different azido bridging ligands are in trans axial position. Mn(Ⅱ) ions are linked by nitrogen atom of μ1,1-azido and oxygen atoms of two carboxy groups to form a Mn-Mn unit. Mn-Mn units are linked by azido ligands through u1,3 bridging style to form a one-dimensional chain. The compound is connected by the coordination bonds,π-π interactions and hydrogen bonds as a three-dimensional structure. Magnetic susceptibility data support that there are stronger antiferromagnetic interactions between the radical and Mn(Ⅱ) ion, weak antiferromagnetic inter  相似文献   

9.
1 INTRODUCTION Macrocyclic ligands and their metal complexes have received much attention due to their applications in ion transport, ion separation and as models in biomimic researches[1~7]. The synthetic methods of macrocyclic ligands and their metal complexes are mainly divided into three kinds[8]. The first one is synthesizing free ligand, then forming the metal complexes; the second is template synthesis; and the third is synthesizing the end-off or side-off precursor ligand, then c…  相似文献   

10.
In their report of the crystal structure of the compound claimed to be [Cu(OH)2(H2O)2(4- C5H4NCOOH)2], the authors did not give any experimental details on the location and refinement of the water and hydroxyl hydrogen atoms[1]; they had assumed the presence of the carboxylic -CO2H unit on the basis of the infrared stretching frequency at 1700 cm-1 that is only of medium intensity. The cell constants for the compound are, in fact, identical, with those documented for tetraaquabis(isonicot…  相似文献   

11.
1 INTRODUCTION Nickel is vital for organism as a trace element and it often acts as component or secondary factor of enzyme. In the latest two decades, biological inor- ganic chemistry of nickel has become one of the hottest fields and the coordination chemistry of nic- kel has made a great progress[1]. Complexes built upon organic aromatic carboxylic acid and metallic ion have attracted chemists’ interest for years due to their potential applications in material, medicine, molecular ele…  相似文献   

12.
1 INTRODUCTION At present, the polyaluminium compounds are mainly studied by single-crystal X-ray diffraction method to obtain the components, structures and exis- tence forms of aluminium in hydrolysis system, and then hydrolysis courses and mechanisms of each hydrolytic polyaluminium cation could be further dis- closed[1~5]. Generally, the single crystals suitable for X-ray diffraction are obtained from the crystallization of polyaluminium cations into sulfates or selenates. Following …  相似文献   

13.
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   

14.
Terbium p-chlorobenzoate complex with 1,10-phenanthroline, [Tb( p-ClBA)_3phen]_2 (1) has been obtained in the ethanol solution, where p-ClBA=p-chlorobenzoate and phen=1,10-phenanthroline. It crystallizes in the triclinic system, space group P1, a=1.008 1(2) nm, b=1.185 7(2) nm, c=1.431 1(3) nm, α=110.826(4)°, β=96.436(4)°, γ=101.737(4)°, Z=2. The two Tb(Ⅲ) ions are linked by four carboxylate groups through their bidentate bridging modes, forming a dimeric unit with crystallographic inversion center. Each terbium ion has an eight-coordinate geometry with four of the coordination sites occupied by four oxygen atoms from the four bridging carboxylates, respectively, two oxygen atoms from bidentate carboxylate, and the remaining positions occupied by two nitrogen atoms from a 1,10-phenanthroline molecule. The Tb(Ⅲ) ion adopt a distorted square antiprism coordination geometry. The excitation and luminescence data observed at room temperature show that the title complex emits very intensive green fluorescence under ultraviolet light. The result of thermal analysis indicates the complex [Tb(p-ClBA)_3phen]_2 is quite stable to heat. CCDC: 221921.  相似文献   

15.
The X-ray crystal structures of (NH4)2(15-crown-5)3[Cu(mnt)2] (1) and (NH4)2(benzo-15-crown-5)4- [Cu(mnt)2]·0.5H2O (2) were determined. Two single crystals are composed of distinct structures of ammonium-crown ether supramolecular cation and [Cu(mnt)2]2? anion. The triple-decker dication in complex 1 and a sandwich dimmer in complex 2 were observed. X-Band EPR studies on the single crystals of both complex 1 and complex 2 have been carried out at room temperature, which revealed that complex 2 showed a perfect hyperfine structure of Cu whereas that of complex 1 could not be observed. The principal values and direction cosines of the principal axes of the g and A tensors were computed by a least-squares fitting procedure. The spin density of Cu(II) was estimated according to the principal values of the A tensors and compared well with the results calculated based on DFT method.  相似文献   

16.
1 INTRODUCTION Crystal engineering principles have been employ- yed in recent years to produce a variety of coordi- nation networks[1], which are of great current interest not only for their potential properties as functional solid materials[2] in host-guest chemistry, ion ex- change and catalysis, but also for their often com- plicated intriguing architectures and topologies. Ra- tional control the construction of polymeric net- works remains a great challenge in crystal engineer- ing. Mu…  相似文献   

17.
<正> The title complex crystallizes in the orthorhombic space group Pna21 with Mr = 570. 8, a = 16. 927(6), b = 18.942(7), c=10. 618(5)(?) and Z = 4. The structure was solved by Patterson and Fourier techniques and refined by block-diagonal least squares techniques to R = 0. 090 and Rw = 0. 093 for 1553 reflections with I>1. 5σ(I). The Pr3+ ion is bonded to five carbon atoms of cyclopentadi-enyl ring, four μ-chlorine atoms and one oxygen atom of THF in an octahedral geometry with the Pr-C distances in the range 2. 6.7 - 2. 79(?)(av. 2. 76(?)) , the Pr-Cl distances in the range 2. 81 - 2. 92(?) (av. 2. 86(?)) and the Pr -O distance of 2. 51 (?). Each Li+ ion is coordinated by two μ-chlorine atoms and two oxygen atoms from THF in a tetrahedral geometry with the Li-Cl distances in the range 2. 24 - 2. 61(?) (av. 2. 43(?)) and the Li -O distances in the range 1. 86-1. 94(?)(av. 1. 91(?)). The Pr atom and the two Li atoms are bridged asymmetrically by the chlorine atoms.  相似文献   

18.
The treatment of(NH_4)_2 OsCl_6 with 2 equiv of bpy in ethylene glycol produced complex 1, cis-Os~Ⅱ(bpy)_2Cl_2(bpy = 2,2?-bipyridine). Its one-electron oxidation product 2, [cis-Os~Ⅲ-(bpy)_2Cl_2](PF_6), was obtained by the oxidation of 1 with(Cp)_2 FePF_6. Complex 1 crystallizes in the orthorhombic space group Pbca, and adopts distorted [MCl_2 N_4] octahedral coordination, in which four coordination sites are occupied by four nitrogen atoms from two bpy ligands and the other two sites are occupied by two chlorine atoms in a cis-position. Complex 2 crystallizes in monoclinic space group C2/c, and contains one [Os(bpy)_2Cl_2]~+ cation, one PF_6~- anion and two uncoordinated water solvent molecules.  相似文献   

19.
The layered compounds LiCoO2, LiNiO2 and spinel compound LiMn2O4 have served as very effective cathode active materials in lithium ion rechargeable batteries. Generally, their high conductive resistance easily results in a serious polarization and poor utilization of active materials. In order to make full use of the active materials and increase the capacity, the charge–discharge rate and the cycle life of lithium ion batteries, conductive additives are often added into the above cathode …  相似文献   

20.
A two-dimensional cyanide-bridged Cu(Ⅱ)-Pt(Ⅱ) bimetallic complex has been synthesized by solution diffusion method using [Pt (CN)4]2- and [Cu (L)]2+ (L =3,10-diethanol-1,3,5,8,10,12-hexaazacyclotetradecane) as building blocks. Unexpectedly, the obtained complex Cu(DMF)2[Pt(CN)4] (1) is an analogue of the well-known Hofmann -type clathrate without macrocyclic ligand. Single-crystal X-ray diffraction reveals that 1 crystallizes in monoclinic, space group C2/m, a=1.624 8(6) nm, b=0.739 3(3) nm, c=0.695 5(3) nm, β=108.969(4)°. The crystal structure of 1 consists of two-dimensional corrugated metal cyanide sheets without interpenetration stacking along the a axis in an ABAB packing mode.  相似文献   

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