Crystal Structure and Luminescent Properties of a 3D Cd(Ⅱ) Compound Constructed from Succinate and 3,6-Di(4-pyridyl)pyridazine

A three-dimensional(3D) coordination polymer,[Cd(SC)(DPPD)]_n(1,H_2SC = succinic acid and DPPD = 3,6-di(4-pyridyl)pyridazine),has been synthesized by the solvothermal reaction of Cd(NO_3)_2·4H_2O with H_2 SC and DPPD at 120 oC in DMF solvent. Compound 1 crystallizes in the monoclinic system,space group P2_1/c,with a = 10.7993(4),b = 11.7705(3),c = 13.5336(6) ?,V = 1678.89(11) ?~3,Z = 4,C18H14N4O_4 Cd,M_r = 462.73,D_c = 1.831 g/cm~3,μ = 1.335 mm~(-1),F(000) = 920.0,the final R = 0.0500 and wR = 0.1567 for 3714 observed reflections with I 2s(I). In compound 1,the Cd(Ⅱ) ions are linked by the SC~(2–) ligands to give a two-dimensional(2D) undulating sheet based on the centrosymmetric dinuclear Cd_2(COO)_2 units. The 2D sheets are further connected by the DPPD ligands to produce a 3D structure,which is a 6-connected(4~4·6·~(10)·8) topological network based on the dinuclear Cd_2(COO)_2 node. Compound 1 exhibits a photoluminescent emission with a maximum at 540 nm upon excitation at 460 nm.     

Synthesis and Crystal Structure of [Cd(NBA)(μ_3-OH)(4,4′-bipy)_(1/2)]_n

A new cadmium polymer [Cd(NBA)(μ3-OH)(4,4′-bipy)1/2]n 1 (NBA = m-nitrobenzoic acid and 4,4′-bipy = 4,4-bipyridine) has been synthesized by hydrothermal reaction. Its structure was determined by single-crystal X-ray diffraction method, and characterized by elemental analysis and IR spectrum. The crystal is of monoclinic, space group C2/c, with a = 15.6912(9), b = 25.9394(15), c = 6.7332(4) ′, β = 114.7700(10)°, V = 2488.4(3) 3, C12H9CdN2O5, Mr = 373.61, Z = 8, Dc = 1.995 g/cm3, μ = 1.776 mm-1, F(000) = 1464, R = 0.0411 and wR = 0.1128 for 2130 observed reflections (I > 2σ(I)). X-ray diffraction studies reveal that the compound features a layered structure, in which 4,4′-bipy ligands bridge Z type of double chains [Cd(μ3-OH)]n and NBA ligands locate at the two sides of the layer. The π-π interactions between the benzene rings of NBA ligands of two adjacent layers lead to the 3D framework.     

Synthesis,Structure and Luminescent Properties of a Two-dimensional Cobalt(Ⅱ) Coordination Polymer Based on 2-Thiobarbituric Acid

A two-dimensional coordination polymer [Co(H_2tba)_2(DMF)_2]_n 1(H_2tba = 2-thiobarbituric acid anion, DMF = N,N-dimethylformamide) has been synthesized by Co Cl2·6H2O with the 2-thiobarbituric acid ligands under solvothermal conditions. Compound 1 was further characterized by FTIR, elemental analysis, TGA and powder XRD techniques. Single-crystal X-ray diffraction studies revealed that the title compound crystallizes in the monoclinic space group Pbca with a = 12.5948(12), b = 11.4269(11), c = 14.8939(15) ?, V = 2143.5(4) ?~3, Z = 4, Dc = 1.523 g·cm-3, F(000) = 1012, μ = 1.038 mm~(-1), R = 0.0358 and w R2 = 0.0888(I 2σ(I)). Single-crystal X-ray diffraction analysis reveals that 1 is the first two-dimensional noninterpenetrating(4, 4) net coordination polymer based on the 2-thiobarbituric acid. Coordination polymer 1 exhibits two luminescent emission spectra at 477 and 489 nm with the excitation peak at 273 nm.     

Syntheses,Structures, and Properties of Three Coordination Polymers: [Cd_2(bpp)_(1.5)(Hbpp)(phen)_2]_n, [Mn_3(Htptc)_2(phen)_2(H_2O)_2]_n,and {[Cu(btc)_(0.5)(1,4-bib)]·2H_2O}_n

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.     

Synthesis and Crystal Structure of [Cd（NBA）（μ3-OH）（4,4＇-bipy）1/2]n

A new cadmium polymer [Cd(NBA)(μ3-OH)(4,4'-bipy)1/2]n 1 (NBA=m-nitrobenzoic acid and 4,4'-bipy=4,4-bipyridine) has been synthesized by hydrothermal reaction. Its structure was determined by single-crystal X-ray diffraction method, and characterized by elemental analysis and IR spectrum. The crystal is of monoclinic, space group C2/c, with a=15.6912(9), b=25.9394(15), c=6.7332(4)(A), β=114.7700(10)°, V=2488.4(3)(A)3, C12H9CdN2O5, Mr=373.61, Z=8, Dc=1.995 g/cm3,μ=1.776 mm-1, F(000)=1464, R=0.0411 and wR=0.1128 for 2130 observed reflections (I ＞ 2σ(I)).X-ray diffraction studies reveal that the compound features a layered structure, in which 4,4'-bipy ligands bridge Z type of double chains [Cd(μ3-OH)]n and NBA ligands locate at the two sides of the layer. The π-π interactions between the benzene rings of NBA ligands of two adjacent layers lead to the 3D framework.     

Syntheses,Structures and Photoluminescent Properties of Cd(Ⅱ) Polymeric Complexes Based on 5-Aminoisophthalic Acid and Bipyridine Co-ligands

Two novel complexes, namely {[Cd(AIP)(4,4?-bpy)]·1.3DMF}n(1) and [Cd(AIP)(2,2?- bpy)]n(2), have been synthesized through solvothermal reaction(H2AIP = 5-aminoisophthalic acid, 2,2?-bpy = 2,2?-bipyridine, 4,4?-bpy = 4,4?-bipyridine, and DMF = N,N?-dimethylformamide) and structurally determined by single-crystal X-ray diffraction. Complex 1 shows a three-dimensional(3D) layer-pillar framework with rectangular channels, while complex 2 displays a two-dimensional(2D) wave net architecture. Furthermore, 1 and 2 were characterized by elemental analysis, infrared spectra(IR), thermal gravimetric analyses(TGA) and fluorescence measurements. The luminescent properties of 1 dispersed in various organic solvents have been investigated systematically, demonstrating high selectivity for acetone via the fluorescence quenching effect.     

A Novel 3-D Zn(Ⅱ) Coordination Polymer for Inhibiting the Human Osteosarcoma Cells Growth

A new three-dimensional Zn(II) coordination polymer, namely [Zn_4(bpydb)_3(tz)2(H_2O)_2]n(1), has been synthesized by the self-assembly reactions of Zn(NO_3)_2·6H_2O, bpydb H_2, Htz and DMF. Single-crystal X-ray structural analysis reveals that compound 1 features a three-dimensional framework structure and is the first example of Zn-containing coordination polymers based on two kinds of ligands bpydb H_2 and Htz. It crystallizes in triclinic, space group P1 with a = 14.9953(12), b = 17.5335(17), c = 20.2381(11) ?, α = 115.225(7), β = 92.329(5), γ = 105.606(8)o, V = 4561.9(7) ?3, Z = 2, F(000) = 1644, Dc = 1.177 Mg/m3, Mr = 1616.76 and μ = 1.098 mm-1. The antitumor activities of compound 1 and its corresponding organic ligands(bpydb H_2 and Htz) were investigated for inhibiting human osteosarcoma cells(MG-63 and U-2 OS) growth by MTT assay. It was found that compared with the two ligands, compound 1 exerted rather potent activities against all of these cell lines.     

Crystal Structure and Magnetic Properties of a Two-dimensional Compound{(Me_2NH_2)_4[Co(SIP)_2]·2(DMF)·3(H_2O)}_n

A new cobalt(II) compound, {(Me2NH2)4[Co(SIP)2]·2(DMF)·3(H2O)}n(1, H3 SIP =5-sulfoisophthalic acid), has been synthesized under solvothermal condition and structurally characterized by single-crystal X-ray diffraction. Compound 1 crystallizes in the tetragonal system,space group P 4 21 m, with a = 14.3080(7), b = 14.3080(7), c = 12.1837(9) ?, V = 2494.2(3) ?~3, Z =2, C_(330)H_(58)N_6O_(19)S_2Co, Mr = 929.87, Dc = 1.238 g/cm, μ = 0.496 mm~(-1), F(000) = 982, flack parameter of 0.007(9), the final R = 0.0767 and wR = 0.2110 for 2391 observed reflections with I 2σ(I). The tetrahedral Co(II) ions are linked by carboxylate groups of the 5-sulfoisophthalate ligands to form an anionic two-dimensional(2D) layer displaying a(4,4) square network, which was charge-balanced by the [Me_2NH_2] + cations occupying the spaces between the 2D layers. Magnetic properties of 1 have been investigated in detail using direct-current and alternating-current susceptibility measurements.     

Syntheses and Crystal Structures of Two Copper(Ⅱ) Coordination Polymers Derived from Aromatic Carboxylic Acids and Bis(imidazoles) Ligands

Two compounds have been obtained by the reaction of metal(Cu(II)), 4,4?-bis(imidazol-l-yl)diphenyl thioether(BIDPT) with two carboxylic acids, 4,4?-oxydibenzoic acid(H_2oba) and phthalic acid(H_2pht). The crystal structures of the resulting compounds, namely {[Cu(BIDPT)(oba)]·H2O}n(1) and {Cu(BIDPT)(pht)}n(2), have been determined by single-crystal X-ray diffraction analysis. Compound 1 is of orthorhombic system, space group Pbcn with a = 27.8310(3), b = 10.7791(1), c = 19.3913(2) ?, V = 5817.0(3) ?3 and Mr = 656.15. Compound 2 belongs to the monoclinic system, space group C2/c with a = 18.2678(2), b = 11.0259(1), c = 22.906(2) ?, β = 97.727(2)o, V = 4571.8(8) ?3 and Mr = 545.04. Structural analyses reveal that compounds 1 and 2 respectively exhibit two-dimensional(2D) wavy and corrugated layer structures. Through intermolecular hydrogen bonding, compound 1 is assembled into a 3D supramolecular structure. The thermal stability and ultraviolet spectroscopy properties of the two compounds are also investigated.     

Synthesis and Crystal Structure of [Cd(NBA)(μ3-OH)(4,4''-bipy)1/2]n

A new cadmium polymer [Cd(NBA)(μ3-OH)(4,4'-bipy)1/2]n 1 (NBA=m-nitrobenzoic acid and 4,4'-bipy=4,4-bipyridine) has been synthesized by hydrothermal reaction. Its structure was determined by single-crystal X-ray diffraction method, and characterized by elemental analysis and IR spectrum. The crystal is of monoclinic, space group C2/c, with a=15.6912(9), b=25.9394(15), c=6.7332(4)(A), β=114.7700(10)°, V=2488.4(3)(A)3, C12H9CdN2O5, Mr=373.61, Z=8, Dc=1.995 g/cm3,μ=1.776 mm-1, F(000)=1464, R=0.0411 and wR=0.1128 for 2130 observed reflections (I ＞ 2σ(I)).X-ray diffraction studies reveal that the compound features a layered structure, in which 4,4'-bipy ligands bridge Z type of double chains [Cd(μ3-OH)]n and NBA ligands locate at the two sides of the layer. The π-π interactions between the benzene rings of NBA ligands of two adjacent layers lead to the 3D framework.     

A Novel （3,4）-Connected Self-penetrating Net, [Cd_3（OABDC）_2（bipy）_2（H_2O）_2]_n

A new luminescent Cd(Ⅱ) compound, [Cd3(OABDC)2(bipy)2(H2O)2]n (1, H3OABDC = 5-oxyacetateisophthalic acid, bipy = 4,4'-bipyridine), has been prepared by the assembly of Cd(Ⅱ) salt with the mixed ligands of H3OABDC and 4,4'-bipy under hydrothermal conditions. The crystal structure is of monoclinic, space group P2/n with a = 13.6730(5), b = 10.1265(3), c = 15.9752(4) , β = 103.061(3)o, V = 2154.70(11) 3, C40H34Cd3N4O18, Mr = 1195.94, Z = 2, Dc = 1.843 g/cm3, F(000) = 1180, μ = 1.549 mm-1, the final R = 0.0409 and wR = 0.1291 for 2746 observed reflections (I > 2σ(I)). Single-crystal X-ray structural analysis reveals that compound 1 features a self-penetrating two-dimensional (2D) layered structure. According to topology analysis, this 2D framework can be characterized as a (3,4)-connected (6.72)2 (62.8)2 (73.8.102) net that has never been reported before. Finally, these 2D layers are further linked by intermolecular hydrogen bonds and π…π interactions to form a three-dimensional (3D) supramolecular framework. Moreover, Compound 1 exhibits strong blue photoluminescence at room temperature.     

Crystal Structures,Luminescent Properties and Hirshfeld Surface Analyses of Zn(Ⅱ) and Cd(Ⅱ) Compounds Based on 1-(2-Carboxyl-phenyl)-3-(pyridin-2-yl)pyrazole

Two compounds,[Zn_2(Hcppp)_2(cppp)_2(H_2O)_2]·2 NO_3·6 H_2O(1) and [Cd(Hcppp)_2Cl_2]· 3H_2O(2)(Hcppp = 1-(2-carboxyl-phenyl)-3-(pyridin-2-yl)pyrazole),are synthesized and characterized by IR,TGA and X-ray single-crystal/powder diffraction.Compound 1 crystallizes in monoclinic system,space group P2_1/c with a = 9.894(2),b = 15.856(3),c = 20.430(4) ?,β = 101.70(3)°,V = 3138.5(11) ?~3,Z = 2,M_r = 1457.94,D_c = 1.543 g/cm~3,F(000) = 1504,R = 0.0278 and wR = 0.0749 for 6157 observed reflections(I 2σ(I)).Compound 2 crystallizes in triclinic system,space group P1 with a = 9.1424(4),b = 11.6427(5),c = 16.1345(7) ?,α = 102.6430(10)°,β = 95.4530(10)°,γ = 104.0060(10)°,V = 1605.94(12) ?~3,Z = 2,M_r = 767.88,D_c = 1.588 g/cm~3,F(000) = 776,R = 0.0307 and wR = 0.0764 for 6275 observed reflections(I 2σ(I)).Compound 1 exhibits a binuclear structure while compound 2 shows a mononuclear structure.In compound 1,two cppp-ligands display the μ_2-kN,N′:k O and two Hcppp ligands show the μ_1-kN,N′ coordination modes.However,two Hcppp ligands connect one Cd(Ⅱ) cation and exhibit the μ_1-kN,N′ binding mode in compound 2.The compounds are both studied using Hirshfeld surface analyses and 2D fingerprint plots.The luminescent properties are also discussed.     

Three New Zn(Ⅱ)/Cd(Ⅱ) Coordination Polymers Constructed with 2-Mercaptonicotinic Acid and 1,2-Di(4-pyridyl)ethylene: Syntheses and Structure Analysis

Three new Zn(Ⅱ)/Cd(Ⅱ) coordination polymers based on 2-mercaptonicotinic acid (H2mna) with 1,2-di(4-pyridyl)ethylene (dpe) introduced as a bridging ligand have been synthesized via hydrothermal method and structurally characterized by single-crystal X-ray diffraction as well as elemental analysis and IR. As reported in this paper, [Zn2(dpe)0.5(mna)2] (1) can be classified as a two-dimensional layer structure in which the 1D chain composed of Zn(Ⅱ) and mna ligands is bridged by dpe ligands, while the complex named [Zn4(dpe)4(mna)4] (2) is a tetra-nuclear cluster compound. These two compounds are further extended to three-dimensional structures by hydrogen bonds along with C-H…π and π…π interactions. Compound 3 with general formular [Cd2(dpe)0.5(mna)2]·H2O belongs to a three-dimensional porous structure in which the 2D metal layers formed by the coordination of Cd(Ⅱ) and mna ligands are connected with the bridging of dpe ligands.     

Hydrothermal Synthesis and Crystal Structure of a Novel Binuclear Cd(Ⅱ) Coordination Polymer Based on 1,2-Benzenedicarboxylate and Imidazole

The hydrothermal reaction of Cd(OAc)2·H2O with 1,2-benzenedicarboxylate(1,2-BDC),imidazole and H2O resulted in the formation of a binuclear polymeric Cd(Ⅱ) complex {[Cd2(1,2-BDC)2(Im)4]·(H2O)}n which was then characterized by elemental analyses and single-crystal X-ray diffraction analysis.The crystal is of monoclinic system,space group P21/c with a = 14.6455(3),b = 9.3530(2),c = 23.7838(5) ,β = 106.6290(10)°,C112H104Cd8N32O36,Mr = 3373.47,V = 3121.64(11) 3,Dc = 1.795 g/cm3,F(000) = 1672,μ = 1.428 cm-1 and Z = 1.The final R = 0.0316 and wR = 0.0687 for 5045 reflections with I > 2σ(I).In the title complex,the two Cd(Ⅱ) ions are in different coordination environments with distorted octahedral and pengonal bipyramidal geometries,respectively.Two Cd polyhedra are linked together through one μ2-η1:η1 and one μ2-η1:η2 carboxylate groups from different 1,2-BDC ligands,giving rise to a binuclear Cd(Ⅱ) cluster,and such clusters are connected by bridged 1,2-BDC ligands to form a 2-D structure along the c axis.The inter-and intermolecular hydrogen bonds further connect the 2-D structures into a 3-D supramolecular network.     

Three Novel Luminescent Zinc(Ⅱ) Compounds Constructed by Employing Mixed-ligand Strategy

Three novel coordination polymers,[Zn(suc)(o-bix)]_n (1),[Zn(suc)(m-bix)·H_2O]_n (2) and[Zn_2(suc)_2(p-bix)_2·4H_2O]_n (3)(H_2suc=succinic acid,o-bix=1,2-bis(imidazol-1-ylmethyl)-benzene,m-bix=1,3-bis(imidazol-1-ylmethyl)-benzene,p-bix=1,4-bis(imidazol-1-ylmethyl)-benzene),have been synthesized and structurally characterized by elemental analysis,IR spectroscopy,thermogravimetric analysis,powder X-ray diffraction,and single-crystal X-ray diffraction.These three coordination polymers present various structures originated from auxiliary N-donor ligands with different configurations.Compound 1 shows a 2D network with4~4-sql topology.Compound 2 exhibits an infinite chain,and the adjacent chains are extended into a 2D sheet byπ-πstacking interactions.Changing the conformation of the N-donor ligand leads to 3 featuring a 3D framework with a novel 4-connected (6~5·8) topology.In addition,the solid-state photoluminescent properties of compounds 1～3 are investigated.     

A New Cadmium（Ⅱ） Coordination Polymer Incorporating a 3D Framework with 1D Channels Bridged by Flexible Cyclohexane-1,2,4,5-tetracarboxylate Ligand

The hydrothermal reaction of Cd(OAc)2·2H2O, 4,4'-bpy and cyclohexane-1,2,4,5-tetracarboxylic acid (H4L) yields a three-dimensional (3D) coordination porous framework [Cd2LI(4,4'-bpy)1.5(H2O)2]n·2nH2O, which was characterized by single-crystal X-ray diffraction (MoKα radiation, λ = 0.71073), elemental analysis and IR. This complex crystallizes in the monoclinic system, space group C2/c with a = 25.951(3), b = 11.6618(12), c = 20.046(2) , β = 114.863(2)o, V = 5504.4(10) 3, Z = 8, Dc = 1.900 g/cm3, Mr = 787.30, μ = 1.615 mm-1, F(000) = 3128, the final R = 0.0978 and wR = 0.1780. The structure of the complex is a 3D coordination Cd-carboxylate framework consisting of 1D hexagonal channels along the c-axis filled with the bridging 4,4'-bpy ligands. The 4,4'-bpy ligands with two kinds of conformations are located alternately in the channels through coordination and hydrogen interactions to support the whole porous framework, in which the conformation-flexible cyclohexane-1,2,4,5-tetracarboxylate ligand adopts the I (e,a,a,e) conformation and acts as a pentadentate ligand to connect five Cd(Ⅱ) atoms via the carboxylate groups in different coordination modes.     

A New Cd(Ⅱ) Coordination Polymer Constructed by 3-(2-Pyridyl)pyrazole and 5-Nitroisophthalic Acid:Synthesis,Crystal Structure and Theoretical Calculations

A new coordination polymer, [Cd_2(NIPH)(L)_2(H_2O)]n(1, HL = 3-(2-pyridyl)pyrazole and H_2NIPH = 5-nitroisophthalic acid), has been synthesized. The structure of complex 1 has been characterized by X-ray single-crystal diffraction, elemental analysis, IR spectrum analysis, thermogravimetric analysis and fluorescence spectrum analysis. Complex 1 belongs to the triclinic system, space group P1 with a = 8.9539(6), b = 11.6252(8), c = 12.2472(8) ?, α = 80.011(2), β = 80.3850(10), γ = 86.773(2)°, V = 1237.37(14) ?~3, Z = 2, D_c = 1.987 g/cm~3, μ = 1.780 mm~(-1), M_r = 740.25, F(000) = 724, the final R = 0.0295 and wR = 0.1015 with I 2σ(I). Two H_2NIPH as monodentate and bidentate ligands and two L ligands link four Cd(Ⅱ) ions to form a tetranuclear subunit. Each pair of the tetranuclear subunits is bridged by NIPH ligands to yield a one-dimensional double-chain structure. Furthermore, the 1D chains are linked into a 3D supramolecular framework with hydrogen bonds and π-π interactions. In addition, we analyzed Natural Bond Orbital(NBO) in using the PBE0/LANL2DZ method built in Gaussian 03 Program. The calculation results indicated the obvious covalent interaction between the coordinated atoms and Cd(Ⅱ) ion.     

Structural Characterization and Proton-conductive Property of a Lanthanide Metal-organic Framework Assembled from 1,2,4,5-Benzenetetracarboxylic Acid and Piperazine

The reaction of Pr(Ⅲ) salt with 1,2,4,5-benzenetetracarboxylic acid(H_4betc) and piperazine(pip) yielded a lanthanide metal-organic framework {[Pr(betc)(H_2O)_2](H_2pip)0.5}n(1)under hydrothermal conditions. Compound 1 was characterized by single-crystal X-ray structural analysis, elemental analysis, IR, X-ray powder diffraction, and thermal gravimetric. Compound 1crystallizes in monoclinic, space group P21/n with a = 11.023(5), b = 11.109(5), c = 11.456(5) ?, β = 110.065(5)°, V = 1317.7(9) ?~3, M_r = 471.14, Z = 4, F(000) = 920, D_c = 2.375 g/cm~3, μ(Mo Kα) = 3.761 mm-1, the final R = 0.0286 and w R = 0.0821(I 2σ(I)). Compound 1 exhibits a 2D network with(4, 4) topology, and a 3D supramolecular framework formed by hydrogen-bonding interactions. The proton conductivity of compound 1 has been investigated at ~97% relative humidity and different temperature.     

Organic Carboxylate Ligand Tuned Topological Variations in Three Zn(Ⅱ) Coordination Polymers: Syntheses,Crystal Structures and Photoluminescent Properties

Three new Zn(Ⅱ) coordination polymers, namely [Zn_2(suc)_2(bib)_2]_n·nH_2 O(1), [Zn(glu)(bib)]_n·4 nH_2 O(2), and [Zn(adp)(bib)]n(3)(bib = 1,4-bis(N-imidazolyl)butane, H_2 suc = succinic acid, H_2 glu = glutaric acid, H_2 adp = adipic acid) have been hydrothermally synthesized and structurally characterized. Compound 1 features a 3D framework with 4-connected hxg-d topological network, compound 2 is comprised of 2D 4~4-sql-type sheets, and the adjacent 2D sheets are further packed into a 3D supramolecular architecture via intermolecular hydrogenbonding interactions, and compound 3 is a 3D framework with 4-fold interpenetrating dia topology. The structural comparison of these three compounds demonstrates that the topological variations can be well controlled by employing aliphatic dicarboxylate ligands with different spacer lengths. Moreover, the thermal stabilities and photoluminescent properties of them were also studied in detail.     

A two-dimensional microporous metal–organic framework for highly selective adsorption of carbon dioxide and acetylene

Solvothermal reaction of 3-aminoisonicotinic acid(Haina) and Cu(NO_3)_2·2.5H_2O gave a novel twodimensional(2D) microporous metal–organic framework, [Cu(aina)_2(DMF)]·DMF(1, DMF = N,N-dimethylformamide). Single-crystal X-ray crystallographic study of compound 1 revealed that Cu(II)ions are linked by ainaàligands forming square grid-like layers, which stack together via multiple hydrogen bonding interactions. The solvent-free framework of 1a displayed considerable porosity(void = 46.5%) with one-dimensional(1D) open channels(4.7 ? ? 4.8 ?) functionalized by amino groups.Gas sorption measurements of 1 revealed selective carbon dioxide(CO_2) and acetylene(C_2H_2) adsorption over methane(CH_4) and nitrogen(N_2) at ambient temperature.