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1.
Four new metal–organic supramolecular networks, namely, [Zn(H2pdc)2(H2O)2]·2H2O·bbi (1), {[Cd(Hpdc)2]·2H2O2·H2bbi}n (2), [Zn(BA)2(bbi)]n (3), and {[Cd(BA)2(bbi)]·H2O}n (4) (H3pdc = 3,5-pyrazoledicarboxylic acid, HBA = 3-hydroxybenzoic acid and bbi = 1,1′-(1,4-butanediyl)bis(imidazole)) have been synthesized under hydrothermal conditions and characterized by IR spectra, elemental analyses, and single-crystal X-ray diffraction analyses. Compound 1 possesses zero-dimensional (0D) structure, which is finally extended into a two-dimensional (2D) supramolecular network via O–H···O and C–H···O hydrogen bonds. Complex 2 displays a 2D network structure built from Cd2+ atoms interconnected by Hpdc2? ligands. The adjacent networks are further assembled into three-dimensional (3D) supramolecular structure through O–H···O hydrogen bonds. Compounds 3 and 4 show similar one-dimensional (1D) chains, in which four-coordinated Zn(II) atoms and six-coordinated Cd(II) atoms are bridged by bbi ligands. Through O–H···O and C-H···O hydrogen bonding interactions, the 1D chains are further packed into 2D and 3D supramolecular frameworks for 3 and 4, respectively. Obviously, the structural differences among compelxes 14 are attributed to the different central metal atoms and organic ligands. In addition, compounds 14 exhibit blue fluorescent emission in the solid state at room temperature.  相似文献   

2.
Two lanthanide-based metal–organic frameworks with flexible alicyclic carboxylate ligands, generally formulated as [Sm(TMG)(HTMG)(H2O)] (1) and [Nd2(CHDC)3(H2O)] (2), have been successfully synthesized and characterized. They represent the first example of lanthanide-TMG and lanthanide-CHDC systems. Their structures range from 1D infinite chains to 2D extended layer structure. Complexes 2 exhibit strong fluorescent emissions in the near-infrared region at room temperature. Interestingly, the structural difference between compounds 1 and 2 indicates the pH values have subtle influence on the coordination modes of ligands and dimension of LMOFs.  相似文献   

3.
Two novel inorganic–organic hybrid frameworks of [Co(2,5-pydc)(4,4′-bipyo)0.5(H2O)3 · 3H2O] n (1) and [Cu1.5Gd(2,5-pydc)3(2,2′-bipyo)(H2O)4 · 2H2O] n (2) (2,5-pydc = pyridine-2,5-dicarboxylic acid; 4,4′-bipyo = 4,4′-bipyridine-N,N′-dioxide; 2,2′-bipyo = 2,2′-bipyridine-N,N′-dioxide) were prepared. Both compounds have been characterized by the elemental analyses, IR spectra, TG analysis and the single crystal diffraction. The salient structural feature for both compounds 1 and 2 is that the 1D chain and the mononuclear fragment are connected by strong hydrogen bond interactions to form 2D structure.  相似文献   

4.
5.
Two new metal–organic entangled frameworks, namely [Cd(FA)0.5(bix)1.5(H2O)] n ·nNO3 (1) and [Cd(FA)(bib)(H2O)2] n (2) (FA = fumaric acid, bix = 4,4′-bis(imidazol-1-ylmethyl)benzene, bib = 1,4-bis(imidazolyl)butane), have been successfully hydrothermally synthesized through mixed ligands strategy. Single crystal X-ray diffraction analysis reveal that 1 is a 2D → 3D polycatenated framework, while 2 is a triply interpenetrated 4-connected dia topological net. Moreover, both compounds exhibit intense luminescence emission at room temperature.  相似文献   

6.
Hydrothermal and solution reactions of pyridine-2,6-dicarboxylic acid N-oxide (2,6-PDCO) and BaCl2·2H2O yield two metal–organic frameworks; namely [Ba(2,6-PDCO)] n (1) and [Ba(2,6-PDCO)·H2O] n (2), respectively. Single-crystal X-ray analyses reveal that compound 1 is a dense framework whereas compound 2 is a porous one, though both compounds have an infinite two-dimensional (2D) layer structure. Compounds 1 and 2 are the first examples of pyridine dicarboxylic acid N-oxide introduced into the alkaline earth metal–organic framework.  相似文献   

7.
Three new coordination polymers, [Ni(2,4′-oba)(1,10-phen)] n (1), {[Ni (2,4′-Hoba)2(4,4′-bipy)(H2O)2]·2H2O} n (2) and [Zn(2,4′-oba) (4,4′-bipy)] n (3) (2,4′-H2oba = 2-(4-carboxyphenoxy)benzoic acid, 1,10- phen = 1,10-phenanthroline, and 4,4′-bipy = 4,4′-bipyridine) have been obtained by hydrothermal synthesis. The framework structures of these polymeric complexes have been determined by single-crystal X-ray diffraction studies. Complex 1 exhibits double-helical chains formed by ππ stacking interactions from the phenyl rings of the 1,10-phen ligands. Complex 2 forms a two-dimensional supramolecular architecture directed by hydrogen bonding. Complex 3 exhibits a three-dimensional structure; Schl?fli symbol of {44·610·8}. The luminescent property of compound 3 is discussed.  相似文献   

8.
Two 1D inorganic–organic hybrid frameworks, namely, [Zn(5-NO2-bdc)(MIM)3·H2O]n(1) and [Cd(MIM)2Br2]n(2) (5-NO2-bdcH2 = 5-nitro-1,3-benzenedicarboxylic acid, MIM = N-methyl imidazole) were synthesized via ionothermal reactions with ionic liquid 1-ethyl-3-methylimidazolium bromide ([EMIM]Br) as solvent and template. Both compounds have been characterized by elemental analyses, spectroscopic analyses, thermogravimetric analysis (TGA) and the single crystal diffraction. The zinc(II) center in compound 1 is a slightly distorted five-coordinate trigonal bipyramid, 5-NO2-bdc2− anions and MIM moieties effectively bridge Zn centers to result in 1D zigzag chains. While Cd(II) center in compound 2 is in an octahedral coordination environment, and two μ2-bridge bromine link two [Cd(MIM)2] moieties to form a 1D chain structure. In addition, complex 2 exhibits strong fluorescent emission in the solid state at room temperature.  相似文献   

9.
Two new metal–organic frameworks (MOFs) based on cadmium(II) ions, 1,2-benzenedicarboxylic acid (BDC), flexible ligand 1,4-bi(1H-imidazol-1-yl)butane (BIIM), coordinated water molecules, [(BIIM)(BDC)(H2O)Cd]3n (1) and copper(II) ions, BIIM, coordinated water, free thiophene-2,5-dicarboxylate (TDC), free water, {[(BIIM)4(H2O)4Cu2]·(TDC)2·(H2O)12}n (2) are prepared and characterized by X-ray diffraction, thermal gravimetric analysis (TGA), infrared (IR) spectrum and the photoluminescence property for complex (1). The X-ray diffraction analysis reveals that the structures of complexes 1 and 2 are 2D structures through the C–H···π stacking interactions (for 1) and the BIIM bridging connections (for 2). The IR spectrum for 1 and 2 are presented in the paper, for 1, the strong peaks at 1399 and 1573 cm?1 are owing to the carboxylic CO2 ? symmetry and asymmetry stretching vibrations of BDC. The features of the IR spectrum are consistent with the single crystal structures. The TGA reveal the water is the first lost material from complex, then the ligands removed, and finally the residues of these two complexes are the metal oxide.  相似文献   

10.
A new flexible triazine-based polycarboxylate metal–organic framework, [Sm2(TTHA)(H2O)4]·9H2O (I) (TTHA = 1,3,5-triazine-2,4,6-triamine hexaacetate), has been synthesized under hydrothermal conditions and characterized by single crystal X-ray diffraction, elemental analysis and FT-IR spectroscopy. Crystal data for I are monoclinic C2/c, a = 12.6974(13) Å, b = 16.7309(12) Å, c = 14.8076(15) Å, β = 91.452(8)°, V = 3,144.7(5) Å3. Each SmIII ion is 9-coordinate in a distorted tri-capped trigonal prismatic geometry; but, the principal inorganic building block is {Sm2O16}, which comprises two of these polyhedra that share an edge. The complex exhibits a three-dimensional open-framework structure of approximately 31 % void volume, which comprises two types of channels oriented in three directions; [0 0 1], [1 1 0] and [?1 1 0]. The network can be simplified into either the cooperite (pts) or anatase (ant) topologies depending on the choice of nodes. The UV–Vis spectra of the compound are dominated by the absorption of the TTHA ligand. Thermogravimetric analysis shows that the loss of channel and coordinated water upon heating occurs in two distinct steps.  相似文献   

11.
Two novel metal–organic frameworks based on 1,3-bis(imidazol-1-ylmethyl)-benzene (m-bix), namely [(Cu4I4)(bix)2] n (1) and [HgI2(bix)] n (2) have been synthesized and characterized by IR, elemental analysis, thermogravimetry, luminescent properties and X-ray crystallography. The structure of compound 1 exhibits a 1D metal–organic chain composed of Cu4I4 clusters and m-bix ligands, and such chains are further united together to generate a 3D supramolecular structure through inter-chain π···π interactions. In compound 2, the HgI2-bix chains interact each other to form a layer structure through π···π interactions, then the layers are extended to 3D supramolecular architecture through intermolecular C–H···π interactions.  相似文献   

12.
We report a simple synthesis of aggregates of individual Pd colloidal nanoparticles linked by bridging ligands that may be used to advance the strong hydrogen storage properties of palladium nanoparticles. The aggregates were characterized by transmission electron microscopy and infrared spectroscopy. The bridged aggregates showed up to 1.0 wt% hydrogen absorption, about 6.7 times that of pristine isocyanide-protected Pd nanoparticles.  相似文献   

13.
Two new metal–organic frameworks; namely, [Cd2(pam)2(bpe)1.5(DMF)2(H2O)] n ·2n(DMF) (1) and [Cd(pam)(bix)] n (2) (H2pam = pamoic acid, bpe = 1,2-di(4-pyridyl)ethylene, bix = 4,4′-bis(imidazol-1-ylmethyl)benzene, DMF = N,N′-dimethylformamide), were solvothermally synthesized via varying the auxiliary ligand. Single crystal X-ray diffraction analysis reveals that compound 1 shows a 2D→3D polythreaded motif based on (3,4)-connected 2D sheets, while compound 2 features a 4-connected sql tetragonal plane net, which further extended into a 3D supramolecular framework through intermolecular CH···π interactions. In addition, the luminescent and thermal stabilities properties of these two compounds were investigated.  相似文献   

14.
Two inorganic–organic hybrid frameworks, namely [Cu2(pdca)2(bibp)(H2O)2]·H2O (1) and [Fe(pdca)(pyco)(H2O)]·H2O (2) (H2pdca = pyridine-2,6-dicarboxylic acid, bibp = 4,4′-bisimidazolylbiphenyl, pyco = picolinate N-oxide) were synthesized via hydrothermal reactions. Both compounds have been characterized by elemental analysis, spectroscopic analysis, thermogravimetric analysis (TGA) and the single crystal diffraction. Complex 1 is dinuclear and five-coordinated copper(II) complex, while complex 2 displays mono-nuclear and six-coordinated iron(III) complex. In the crystal structures of both complexes, the coordinated and crystalline water molecules and H2pdca ligands contribute to the formation of O–H···O and C–H···O hydrogen bonds, which link the molecules into layers parallel. Cyclic voltammetry (CV) analysis shows one reversible reduction potential at 0.14 V (Epc) in complex 1, whereas in complex 2 shows a reduction potential at 0.15 V (Epc) in the cathodic region.  相似文献   

15.
Three new isostructural 3D lanthanide MOFs (Ln(HBPTC)(H2O)) (Ln = Tb (1), Pr (2), Nd (3); H4BPTC = 3,3′,4,4′-biphenyltetracarboxylic acid) have been synthesized under hydrothermal conditions using imidazole as a structure-directing agent, and characterized by elemental analyses, IR, thermogravimetric analyses (TGA) and powder X-ray diffraction (PXRD) analyses. Topologically, compounds 13 demonstrate an intriguing 3D (6, 6)-connected network with the Schläfli symbol of (410·65)(49·66); and if the dinuclear (Ln2) clusters are considered as the single 8-connected nodes, they can be described as a scarcely reported (4, 8)-connected alb net constructed from two intertwining sqp-4 nets. TGA and PXRD analyses reveal that compounds 13 exhibit high thermal stability, at least being stable up to 410 °C. Furthermore, the luminescence studies were performed on compound 1 and its dehydrated phase in the solid state at room temperature. The results demonstrate that compound 1 displays intense green emission, implying its potential application as fluorescence material. And the luminescence of 1 is quenched when removing the coordinated water molecules.  相似文献   

16.
Three new metal–organic coordination complexes, [Zn2L(bpp)2Cl2] n (1), [ZnL(bipy)] n (2), [NiL(bipy)(H2O)] n (3), have been synthesized through hydrothermal reactions of flexible 3-(4-(carboxymethoxy)phenyl) propanoic acid(H2L) with different pyridyl-containing 1,3-bis(4-pyridyl)propane(bpp) or 4,4′-bipyridine(bipy) ligand, and they are characterized by elemetal analysis and single-crystal X-ray diffraction techniques. Complex 1 has a 2-D layer supramolecular network composed of 1-D distorted trapezoidal chains via C–H···π stacking interactions. Complex 2 displays a 2-D lattice-shaped layer structure. Complex 3 has three kinds of O–H···O intermolecular hydrogen bonds, exhibiting a 3-D supramolecular framework. The luminescent properties of complex 1 and 2 have indicated the mixture characteristic of intraligand and ligand-to-ligand charge transition. The magnetic property of 3 has shown the ferromagnetic coupling between Ni2+ ions.  相似文献   

17.
A novel metal–organic framework {[Zn(2,3-pydc)(bbi)]·0.5CH3CN·2H2O} n (2,3-pydc = pyridine-2,3-dicarboxylate, bbi = 1,1′-(1,4-butanediyl)bis(imidazole)) (1), was prepared under hydrothermal conditions and characterized by elemental analyses, IR and X-ray diffraction. Crystal data for 1 are monoclinic, space group C2/c, a = 19.685(2) Å, b = 14.332(1) Å, c = 16.930(2) Å, β = 121.205(2)°, U = 4085.3(6) Å3, Z = 4. The results reveal that the Zn(II)-atom is five-coordinated with two O-atoms and three N-atoms forming a distorted trigonal bipyramidal geometry. The Zn(II) atoms are bridged by 2,3-pydc and bbi ligands, leading to a three-dimensional network. The Zn···Zn separations are 8.277 Å [through the 2,3-pydc bridge] and 12.638 Å [through the bbi bridge]. Additionally, 1 shows strong fluorescence in the solid state at room temperature.  相似文献   

18.
A flexible polycarboxyl ligand of tetrahydrofuran-2,3,4,5-tetracarboxylic acid (H4THFTCA) and a common rigid aromatic ligand of 1,10-phenanthroline (phen) have been successfully co-assembled with Cu(NO3)2·3H2O to give out a novel 3D supramolecular metal–organic framework (MOF) compound, [Cu2(THFTCA)(phen)(H2O)2·CH3CH2OH·3H2O] n (1), by a solution self-assembly process. Compound 1 has been characterized as a 2D layered coordination polymer constructed by THFTCA4? and Cu2+ ions, and the layer present a novel (3.52)(32.53.64.7) topological network. Interestingly, the layers are fused each other via strong π–π stacking interactions among adjacent ligands of the terminal phen, so that a 3D supramolecular MOF with 1D rhomboidal tunnels array is formed. The thermogravimetric analysis and corresponding powder X-ray diffraction analysis have revealed that the tunnels structure of 1 could be retained after all guest molecules are removed, and the framework could resist the collapse even heating up to 210?°C. An opinion has also been proposed that the larger accessible volume of the guests means the larger stress on the backbone of the MOF after the guests are removed, and the stress is harmful to the stability of the supramolecular porous structure. Finally, the application properties based on the porous structure have also been primarily evaluated.  相似文献   

19.
20.
Characterization and synthesis of novel cyano bridged coordination compounds [Ni(bishydeten)Pt(CN)4] (1), [Cu(bishydeten)Pt(CN)4] (2), [Zn(bishydeten)Pt(CN)4] (3), [Cd(bishydeten)Pt(CN)4] (4) [bishydeten = N,N′-bis(2-hydroxyethyl)ethylenediamine (C6H16N2O2)] were reported herein. The IR spectra of these coordination compounds verified the formation of aforementioned complexes. The ground state of the paramagnetic electron in the CuII located in tetragonal distorted octahedral sites (D 4h ) was found to be dx2−y2 for complex 2. As for complex 1, an EPR signal was not observed because of diamagnetic property of the PtII and momentary relaxation times of the NiII. All complexes followed identical decomposition mechanism in thermal analysis and thermal stabilities of complexes changed in the order of 1 > 4 > 3 > 2. Both 3 and 4 exhibit polymeric structure according to X-ray single structure analysis. While bishydeten coordinated with three donor atoms (N,N′, and O) in complex 3, it acts as a bidentate ligand (N, and N′) in complex 4. Magnetic properties of complexes 12 at 15–300 K temperature range were determined as antiferromagnetic with Weiss constants = −2.619 and −0.847 K respectively.  相似文献   

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