A 4-fold interpenetrated metal-organic diamondoid framework: synthesis,crystal structure,and properties

The coordination polymer, [Cu₂(bpp)₄Cl₂]Cl₂, was prepared by self-assembly of benzo[f] [1,10]phenanthroline-6,7-dicarboxylic acid and bpp [bpp = 1,3-bis(4-pyridyl)propane] with CuCl₂·2H₂O, and determined by X-ray crystallographic diffraction, IR spectrum, and thermal analysis. The complex features a 3-D 4-fold interpenetrated metal–organic framework with diamondoid topology. There are two sets of diamondoid frameworks independently constructed by bpp bridging the same copper centers, and the two sets of diamondoid frameworks interpenetrate one another to form an interesting 4-fold interpenetrating 3-D architecture.     

A series of novel lanthanide carboxyphosphonates with a 3D framework structure: synthesis, structure, and luminescent and magnetic properties

By introduction of 1,4-benzenedicarboxylic acid as the second organic ligand, a series of novel lanthanide carboxyphosphonates with a 3D framework structure, namely, [Ln(3)(H(2)L)(HL)(2)(bdc)(2)(H(2)O)]·7H(2)O (Ln = La (), Ce (), Pr (), Nd (), Sm (), Eu (), Gd (), Tb (); H(3)L = H(2)O(3)PCH(2)NC(5)H(9)COOH; H(2)bdc = HOOCC(6)H(4)COOH) have been synthesized under hydrothermal conditions. Compounds are isostructural and feature a 3D framework in which Ln(iii) polyhedra are interconnected by bridging {CPO(3)} tetrahedra into 2D inorganic layers parallel to the ab plane. The organic groups of H(2)L(-) are grafted on the two sides of the layer. These layers are further cross-linked by the bdc(2-) ligands from one layer to the Ln atoms from the other into a pillared-layered architecture with one-dimensional channel system along the a axis. The thermal stability of compounds has been investigated. Luminescent properties of compounds , and the magnetic properties of compound have also been studied.     

Solid-state single-crystal-to-single-crystal transformation from a 2D layer to a 3D framework mediated by lattice iodine release

We describe an exceedingly rare example of solid-state single-crystal-to-single-crystal transformation from a 2D layer to a known 3D framework via lattice iodine release, which involves the formation of a new Cu-O ligand bond and a change in the metal coordination geometry.     

A microporous lanthanide metal-organic framework containing channels:Synthesis,structure,gas adsorption and magnetic properties

Under solvothermal condition,the reaction of furan-2,5-dicaboxylate(H2FDA) and glycol with Gd(NO3)3.6H2O gave microporous lanthanide metal-organic framework(MOF),{[Gd(FDA)1.5(glycol)].1.5H2O}}n(1).This compound was characterized by single crystal X-ray diffraction,infrared spectroscopy,elemental analysis,thermogravimetry analysis,and powder X-ray diffraction.The Gd(III) ions were connected by carboxylic group of FDA2-to give 1D chains,which were further linked by FDA2-,forming a 3D porous framework with 3D ...     

Structural variation from linear,layer to 3D framework: Syntheses,structures and luminescence

Self‐assembly of Zn (II) or Cd (II) nitrates, flexible bis (pyridyl)‐diamine, as well as arenesulfonic acids, leads to the formation of ten coordination polymers, namely, [Zn(L1)(H₂O)₃]·2(p‐TS)·2H₂O ( 1 ), [Zn(L1)(H₂O)₂]·2(p‐TS)·2H₂O ( 2 ), [Zn(L1)₂(p‐TS)₂] ( 3 ), [Zn(H₂L1)(H₂O)₄]·2(1,5‐NDS)·2H₂O ( 4 ), [Zn(H₂L2)(H₂O)₄]·2(1,5‐NDS)·4MeOH ( 5 ), [Cd(L1)(p‐TS)(NO₃)]·H₂O ( 6 ), [Cd(L1)(1,5 ‐NDS)_0.5(H₂O)]·0.5(1,5‐NDS)·H₂O ( 7 ), [Cd(L2)(H₂O)₂]·(p‐TS)·(NO₃)·3H₂O ( 8 ), [Cd(L2)(1,5‐NDS)] ( 9 ) and [Cd(L2)(1,5‐NDS)]·MeOH ( 10 ) (L1 = N,N′‐bis (pyridin‐4‐ylmethyl) ethane‐1,2‐diamine, L2 = N,N′‐bis (pyridin‐3‐ylmethy l)ethane‐1,2‐diamine, p‐HTS = p‐toluenesulfonic acid, 1,5‐H₂NDS = 1,5‐naphthalene disulfonic acid), which have been characterized by elemental analysis, IR, TG, PL, powder and single‐crystal X‐ray diffraction. Complexes 1 , 4 , 5 and 6 present linear or zigzag chain structures accomplished by the interconnection of adjacent M (II) cations through L1 ligands or protonated H₂L1²⁺/H₂L2²⁺ cations, while complexes 2 , 3 and 8 show similar (4,4) layer motifs constructed from the connection of M (II) cations through L1 and L2. The same coordination modes of L1 and L2 in complexes 7 and 9 join adjacent Cd (II) cations to form double chain structures, which are further connected by bis‐monodentate 1,5‐NDS^2? dianions into different (6,3) and (4,4) layer motifs. The L2 molecules in complex 10 join adjacent Cd (II) cations together with 1,5‐NDS^2? dianions to form 3D network with hxl topology. Therefore, the diverse coordination modes of the bis (pyridyl) ligand with chelating spacer and the feature of different arenesulfonate anions can effectively influence the architectures of these complexes. Luminescent investigation reveals that the emission maximum of these complexes varies from 374 to 448 nm in the solid state at room temperature, in which complexes 4 , 5 , 7 , 9 and 10 show average luminescence lifetimes from 7.20 to 14.82 ns. Moreover, photocatalytic properties of complexes 7–10 towards Methylene blue under Xe lamp irradiation are also discussed.     

Syntheses,structure and characterization of a fourfold interpenetrated 3D Cd(II) organic framework constructed with a zwitterionic ligand

A 3-D cadmium(II) organic framework with a fourfold interpenetrated diamond topological structure, {[CdLBDC]·(H₂O)₂}_n (1), was synthesized through zwitterionic ligand H₃LBr₃ (1,1′,1″-(2,4,6-trimethylbenzene-1,3,5-triyl)-tris(methylene)tris(4-carboxypyridinium)tribromide), secondary ligand H₂BDC (1,4-benzenedicarboxylic acid) and Cd(NO₃)₂·4H₂O by solvothermal method. Compound 1 was characterized by elemental analyses, FT-IR spectroscopy, powder, and single-crystal X-ray diffraction and thermogravimetric analysis. The photophysical properties of 1 were investigated by solid-state diffuse reflectance spectrum. In 1, each L is linked by two separate Cd(II)-centered distorted tetrahedra, which are also linked by two L, thereby forming a head-to-tail connected 2-D layer structure and further building the 3-D framework through BDC^2?-chelating-bridging between layers.     

A Cu(II) coordination framework constructed by the inorganic layer and a bent dipyridyl ligand: Synthesis,structure and magnetic properties

A new Cu(II) coordination framework {[Cu(4-abpt)(μ₃-SO₄^2-)(H₂O)]·3H₂O}_∞ (1) based on the Cu–SO₄^2- inorganic layer and the bent dipyridyl ligand was obtained under solvothermal conditions (4-abpt ​= ​4-amino-3,5-bis(4-pyridyl)-1,2,4-triazole). The compound displays a three-dimensional (3D) “pillar-layer” framework, which can be simplified into a 3,5-connected gra topology. Furthermore, the magnetic properties of 1 have been investigated. As a result, compound 1 displays a weak antiferromagnetic interaction among the Cu(II) centers.     

Design,synthesis and structure of uranyl coordination polymers from 2-D layer to 3-D network structure

Solvothermal reaction of uranyl acetate and succinic acid in DMF resulted in formation of three uranyl coordination polymers, [(UO₂)₄(μ₂-OH)₇(OH)₆]·2(H₂O)·(H₃O)·4NH₂(CH₃)₂ (1), [(UO₂)(μ₂-OH)(OH)₃]·2NH₂(CH₃)₂] (2), and [(DMF)₂(UO₂)(μ₂-OH)₄(UO₂))] (3). The products were characterized by elemental analysis, IR spectroscopy, X-ray single crystal, and powder diffraction. Structural analysis shows that 1 is a layer, 2 and 3 are 3-D network structures.     

Two interpenetrating 3D MOFs constructed by bis(imidazole) and V-shape carboxylate co-ligands: synthesis,structure, gas adsorption and photoluminescent properties

Two 3-D MOFs, {[Co₂(oba)₂(bmip)]·DMA}_n (1) and [Cd(1,3-bdc)(bmip)]_n (2), where H₂oba = 4,4′-oxybis(benzoic acid), 1,3-bdc = isophthalic acid and bmip = 1,3-bis(2-methylimidazolyl)propane, were synthesized under solvothermal conditions and characterized by single-crystal X-ray diffraction, powder XRD, FT-IR, TGA, and elemental analysis. Complex 1 features a 3-D→3-D twofold interpenetrating framework, and topological analysis shows the framework can be described as a 6-connected uninodal pcu net having the point symbol (4¹².6³). Complex 2 shows a 3-D→3-D threefold interpenetrating network that can be described as a 4-connected uninodal cds net with (6⁵.8) topology. Gas adsorptions of 1 were carried out, and photoluminescent properties of 1 and 2 were also investigated at room temperature.     

Hierarchical assembly of a homochiral triple concentric helical system in a novel 3D supramolecular metal-organic framework: synthesis, crystal structure, and SHG properties

The hierarchical assembly of a homochiral triple concentric helical system in a novel 3D metal-organic framework with SHG activity has been observed. The result also provides a better understanding of host-guest chemistry and the process of water transport in biological systems.     

Rational construction of 3D pillared metal-organic frameworks: synthesis, structures, and hydrogen adsorption properties

In our efforts toward rational design and systematic synthesis of 'pillar-layer' structure MOFs, three porous MOFs have been constructed based on [Zn(4)(bpta)(2)(H(2)O)(2)] (H(4)bpta = 1,1'-biphenyl-2,2',6,6'-tetracarboxylic acid) layers and three different bipyridine pillar ligands. The resulted MOFs show similar structures but different pore volume and window size depending on the length of pillar ligands which resulted in distinct gas adsorption properties. In the three MOFs, [Zn(4)(bpta)(2)(4,4'-bipy)(2)(H(2)O)(2)]·(DMF)(3)·H(2)O (1) (DMF = N,N'-dimethylformamide and 4,4'-bipy = 4,4'-bipyridine) reveals selective adsorption of H(2) over N(2) and O(2) as the result of narrow pore size. [Zn(4)(bpta)(2)(azpy)(2)(H(2)O)(2)]·(DMF)(4)·(H(2)O)(3) (2) and [Zn(4)(bpta)(2)(dipytz)(2)(H(2)O)(2)]·(DMF)(4)·H(2)O (3) (azpy =4,4'-azopyridine, dipytz = di-3,6-(4-pyridyl)-1,2,4,5-tetrazine) reveal pore structure change upon different activation conditions. In addition, the samples activated under different conditions show distinct adsorption behaviors of N(2) and O(2) gases. Furthermore, hydrogen adsorption properties of activated 1-3 were studied. The results indicated that the activation process could affect the hydrogen enthalpy of adsorption.     

CoMn2O4 spinel from a MOF: synthesis, structure and magnetic studies

A hydrothermal reaction of Mn(OAc)(2)·4H(2)O, Co(OAc)(2)·4H(2)O and 1,2,4 benzenetricarboxylic acid at 220 °C for 24 h gives rise to a mixed metal MOF compound, [CoMn(2){C(6)H(3)(COO)(3)}(2)], I. The structure is formed by the connectivity between octahedral CoO(6) and trigonal prism MnO(6) units connected through their vertices forming a Kagome layer, which are pillared by the trimellitate. Magnetic susceptibility studies on the MOF compound indicate a canted anti-ferromagnetic behavior, due to the large antisymmetric DM interaction between the M(2+) ions (M = Mn, Co). Thermal decomposition studies indicate that the MOF compound forms a tetragonal mixed-metal spinel phase, CoMn(2)O(4), with particle sizes in the nano regime at 400 °C. The particle size of the CoMn(2)O(4) can be controlled by varying the decomposition temperature of the parent MOF compound. Magnetic studies of the CoMn(2)O(4) compound suggests that the coercivity and the ferrimagnetic ordering temperatures are dependent on the particle size.     

High heat of hydrogen adsorption and guest-responsive magnetic modulation in a 3D porous pillared-layer coordination framework

A bimetallic pillared-layer coordination framework {[Mn(3)(bipy)(3)(H(2)O)(4)][Cr(CN)(6)](2)·2(bipy)·4(H(2)O)}(n) has been constructed using a cyanometallate anion ([Cr(CN)(6)](3-)) and an organic linker (4,4'-bipyridyl) that provides high heat of hydrogen adsorption (～11.5 kJ mol(-1)) and shows guest dependent magnetic modulation.     

New three-dimensional porous metal organic framework with tetrazole functionalized aromatic carboxylic Acid: synthesis, structure, and gas adsorption properties

5-(1H-Tetrazol-1-yl)isophthalic acid (H(2)L) reacts with Cu(II) ion forming a new metal-organic framework {[CuL]·DMF·H(2)O}(∞) (1) (DMF = N,N-dimethylformamide), with a rutile-related type net topology. Compound 1 possesses a 3D structure with 1D channels that can be desolvated to yield a microporous material. Adsorption properties (N(2), H(2), O(2), CO(2), and CH(4)) of the desolvated solid [CuL] (1a) have been studied, and the results exhibit that 1a possesses fairly good capability of gas sorption for N(2), H(2), O(2), and CO(2) gases, with high selectivity ratios for O(2) over H(2) at 77 K and CO(2) over CH(4) at 195, 273, and 298 K. Furthermore, 1a has excellent O(2) uptake at 77 K and a remarkably high quantity of adsorption for CO(2) at room temperature (298 K) and atmospheric pressure, suggesting its potential applications in gas separation or purification.     

Heterotrimetallic 4f-3d coordination polymers: synthesis, crystal structure, and magnetic properties

A series of cyano-bridged heterotrimetallic complexes [CuL](2)Ln(H(2)O)(2)M(CN)(6).7H(2)O have been synthesized by the reactions of CuL (L(2)(-) = dianion of 1,4,8,11-tetraazacyclotradecane-2,3-dione), Ln(3+) (Ln = Gd or La), and [M(CN)(6)](3)(-) (M = Co, Fe, or Cr). X-ray diffraction analysis reveals that these complexes are isostructural and have a novel chain structure. The Ln(3+) ion is eight-coordinated by six oxygen atoms of two CuL and two water molecules and two nitrogen atoms of the bridging cyano ligands of two [M(CN)(6)](3)(-), while the [M(CN)(6)](3)(-) anion connects two Ln(3+) using two trans-CN(-) ligands giving rise to a chainlike structure. In the chain, every CuL group tilts toward the CN(-) ligand of adjacent [M(CN)(6)](3)(-) with the Cu-N(cyano) contacts ranging from 2.864(6) to 2.930(6) A. Magnetic studies on the CuGdCo complex (1) indicate the presence of ferromagnetic coupling between Cu(II) and Gd(III). The CuLaCr (5) and CuLaFe (2) complexes exhibit ferromagnetic interaction between paramagnetic Cu(II) and Cr(III)/Fe(III) ions through the weak cyano bridges (Cu-N(cyano) = 2.930(6) A for 2). A global ferromagnetic interaction is operative in the CuGdFe complex (3) with the concurrence of dominant ferromagnetic Cu(II)-Gd(III) and minor antiferromagnetic Gd(III)-Fe(III) as well as the ferromagnetic Cu(II)-Fe(III) interaction. For the CuGdCr complex (4), an overall antiferromagnetic behavior was observed, which is attributed to the presence of dominant antiferromagnetic Cr(III)-Gd(III) coupling and the minor ferromagnetic Cu(II)-Gd(III) and Cu(II)-Cr(III) interaction. Moreover, a spin frustration phenomenon was found in complex 4, which results from the ferro-ferro-antiferromagnetic exchanges in the trigonal Cu-Gd-Cr units. The magnetic susceptibilities of these complexes were simulated using suitable models. The magneto-structural correlation was investigated. These complexes did not show a magnetic phase transition down to 1.8 K.     

A three‐dimensional twofold interpenetrated cobalt(II) MOF containing a flexible carboxylate‐based ligand: synthesis,structure and magnetic properties

The design and synthesis of coordination polymers (CPs) have attracted much interest due to the intriguing diversity of their architectures and topologies. The functional solid catena‐poly[μ₂‐aqua‐triaqua{μ₄‐5‐[4‐carboxyphenoxy)methyl]benzene‐1,3‐dicarboxylato}{μ₃‐5‐[4‐carboxyphenoxy)methyl]benzene‐1,3‐dicarboxylato}dicobalt(II)], [Co₂(C₁₆H₁₀O₇)₂(H₂O)₄]_n or [Co₂(HL)₂(μ₂‐H₂O)(H₂O)₃]_n, was synthesized successfully by self‐assembly of Co^II ions with 5‐[(4‐carboxyphenoxy)methyl]isophthalic acid (H₃L). The title compound was obtained under hydrothermal conditions and exhibits a twofold interpenetrated three‐dimensional skeleton with hms 3,5‐conn topology according to the cluster representation for valence‐bonded metal–organic frameworks (MOFs). It has been characterized by single‐crystal X‐ray diffraction, IR spectroscopy, powder X‐ray diffraction (PXRD), thermogravimetric analysis and susceptibility measurements. The antiferromagnetic coupling between adjacent Co^II centres occurs via superexchange through the ligands.     

A vanadium (VO2+) metal-organic framework: selective vapor adsorption, magnetic properties, and use as a precursor for a polyoxovanadate

The reaction of VOSO(4) with 2-carboxyethylphosphonic acid (H(2)-CEP) in presence of piperazine (PIP) produces a 3D inorganic-organic hybrid framework, {(H(2)PIP)(0.5)[VO(CEP)]·H(2)O} (1) with bidirectional channels occupied by the H(2)PIP cations and H(2)O molecules. The PO(3)(2-) unit of CEP connects three V(IV) centers to generate a 1D ladder, which is further linked to four such ladders by the CEP linkers to form a 3D hybrid framework. The dehydrated framework, {(H(2)PIP)(0.5)[VO(CEP)]} (1') shows selective and gated adsorption behavior with H(2)O but not with methanol and ethanol. Very interestingly, when 1 is treated with an aqueous solution of LiNO(3)/NaNO(3), the framework breaks down and results in a new polyoxovanadate (POV) cluster, [H(5)(H(2)PIP)(3)][V(V)(12)V(IV)(2)O(38)(PO(4))]·8H(2)O (2) at pH ≈ 2.1. The cluster has been characterized by single-crystal X-ray diffraction, (31)P NMR, EPR, and magnetic studies. The temperature-dependent magnetic susceptibility measurement suggests antiferromagnetic ordering in 1 with T(N) ≈ 3.8 K.     

Di-radical dinuclear copper complex: synthesis,structure, and magnetic properties

The reaction of Cu(Ac)₂·4H₂O with 2-[(3,5-dichloro-2-hydroxy-benzylidene)-amino]-2hydroxymethyl-propane-1,3-diol (H₄L) and 4,4′-bipyridyl-N,N′-dioxide (4,4′-bipy-NO) in DMF under solvothermal conditions leads to the formation of a di-radical dinuclear copper complex [Cu₂(4,4′-bipy-NO)(dcdmap)₄] (1) (dcdmap is the anion of 2,4-dichloro-6dimethylaminomethyl-phenol, synthesized by an in situ reaction). Compound 1 was characterized by elemental analysis, IR spectroscopy, and X-ray single-crystal diffraction. Complex 1 displays dominant anti-ferromagnetic interaction between oxyradicals and copper ion and oxyradical.     

Synthesis, structure and magnetic properties of Nd3+ and Pr3+ 2D polymers with tetrafluoro-p-phthalate

Two lanthanide tetrafluoro-p-phthalate (L(2-)) complexes, Ln(L)(1.5)·DMF·H(2)O (Ln = Pr(3+) (1), Nd(3+) (2)), were synthesized using pyridine as a base. The compounds were found to be isostructural, and the structure of 1 has been determined by single crystal X-ray diffraction (monoclinic, space group C2, a = 22.194(2) ?, b = 11.4347(12) ?, c = 11.7160(12) ?, β = 94.703(2)°, V = 2963.3(5) ?(3), Z = 4). The crystal structure of 1 consists of dinuclear Pr(3+) units, which are connected by tetrafluoro-p-phthalate, forming separate 2D polymeric layers. The Ln(3+) ions in the dinuclear Ln(2) units are linked by two μ-O atoms and by two bridging O-C-O groups. The structure is porous with DMF and water molecules located between layers. Non-coordinated DMF molecules occupy about 27% of the unit cell volume. A systematic analysis of reported structures of Ln(III) polymers with p-phthalate and its derivatives shows that the ca. known 60 structures can be divided into six possible structural types depending on the presence of certain structural motifs. The magnetic properties of compounds 1 and 2 were studied. The dependence of χ(M)T on T (where χ(M) is magnetic susceptibility per dinuclear lanthanide unit) for 1 and 2 was simulated using two different models, based on: (i) the Hamiltonian ? = Δ?(z)(2)+ μ(B)g(J)H?, which utilises an axial splitting parameter Δ and temperature-independent paramagnetism (tip) and (ii) crystal field splitting. It was found that both models gave satisfactory fits, indicating that the Ln-Ln exchange interactions are small and the symmetry of the coordination environment is the main factor influencing the magnetic properties of these compounds.     

3D architectures of iron molybdate: phase selective synthesis, growth mechanism, and magnetic properties

Monoclinic and orthorhombic Fe(2)(MoO(4))(3) microsized particles with complex 3D architectures have been selectively prepared by a template-free hydrothermal process. The pH value, reaction time, temperature, and molybdenian source have crucial influence on the phase formation, shape evolution, and microstructures. Monoclinic Fe(2)(MoO(4))(3) particles obtained at pH 1 and pH 1.65 display ferromagnetic ordering at 10.4 K and 10.5 K, respectively, and the ferromagnetic component is determined to be 0.0458 mu(B) and 0.0349 mu(B) per Fe-ion at 10 K, respectively. For orthorhombic beta-Fe(2)(MoO(4))(3), antiferromagnetic ordering was observed about 12 K. At higher temperatures, beta-Fe(2)(MoO(4))(3) began to follow the Curie-Weiss law with theta=-70 K. Such 3D architectures of monoclinic and orthorhombic beta-Fe(2)(MoO(4))(3) microparticles with unique shapes and structural characteristics may find applications as catalysts and as well as in other fields.