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Two novel coordination polymers have been hydrothermally synthesized by reactions of Cu(II) salt with 2,2′-phosphinico-dibenzoic acid (H3L), namely, [Cu6L4(H2O)10]·8H2O (1) and [Cu3L2(4,4′-bipy)2(H2O)2] (2). Both compounds were well characterized by single crystal X-ray diffraction, elemental analysis, IR spectroscopic, powder X-ray diffraction and thermal analyses. Compound 1 crystallizes in a noncentrosymmetric monoclinic Pc space group and presents a ladder-like chain structure. In the structure of 1, Cu6 ions are attached to one side of the ladder through carboxylate group generating a novel noncentrosymmetric chain. Magnetic studies indicate that compound 1 exhibits a typical ferrimagnetic behavior. Compound 2 crystallizes in a monoclinic P21/c space group and presents a three-dimensional framework architecture. Compounds 1 and 2 show catalytic activities for the degradation of methylene blue in aqueous solution.

The solution reactions of metal salts with (+)-dibenzoyl-tartaric acid (H2L) and 1,3-bis(4-pyridyl)propane (bpp) or 4,4′-bipyridine (4,4′-bipy) afford three two-dimensional (2D) coordination polymers, [Mn2L2(bpp)2(H2O)4]n·nH2O (1), [CuL(bpp)]n·nH2O (2) and [CoL(4,4′-bipy)(CH3OH)(H2O)]n (3). Dibenzoyl-tartrate ligand displays cis- or trans-conformation, and acts as a 1,4-dicarboxylate linker. Complex 1 features a beautiful 2D double-layered (4,4) network containing [Mn4L2(bpp)4] tetrahedral cage. The flexible bpp ligand links Mn(II) to form an interesting 64-membered saddle-shaped macrocycle [Mn4(bpp)4]. Complex 2 displays a 2D wave-like network assembled by 1D [CuL]n linear chain and 1D [Cu(bpp)]n zigzag chain. Complex 3 is a 2D layered network constructing from [CoL(CH3OH)(H2O)]n chain and [Co(4,4′-bipy)]n chain.

Two 3D coordination polymers with the formulas: [Mn(HL)(H2O)]·0.5H2O (1) and [Cu3(L)2(H2O)2]·2H2O (2), were harvested by self-assembly of Mn(II) and Cu(II) metal ions with 4,4′-phosphinicobis-dibenzoic acid (H3L) through solvothermal process. With various characterization methods, their structures were confirmed. Both 1 and 2 crystallize in the monoclinic P21/c space group. In 1, each quadrangular tube links four other ones by phosphinates to produce a porous three-dimensional (3D) framework. Compound 2 contains the inorganic chains formed by paddle-wheel [Cu2(COO)4] unit and Cu(II) ions in alternate arrangement concatenated by phosphinates. Those chains grow up to a 3D network with the total accessible volume being 49.2% per unit cell volume. Magnetic analysis reveals that 1 and 2 display antiferromagnetic behavior.

Three copper(I) cyanide coordination polymers, namely [Cu8(CN)8(btmb)2]n (1), [Cu(CN)(btmb)0.5]n (2) and [Cu2(CN)2(dpa)]n (3) (btmb = 1,4-bis(1,2,4-triazol-1-ylmethyl)benzene, dpa = di(4-pyridyl)amine), were synthesized under hydrothermal conditions and characterized by elemental analyses, IR spectra, PXRD and thermogravimetric analyses. Single-crystal X-ray diffraction analyses reveal that complex 1 is an interesting 2D double-layered network constructing from eight distinct Cu(I) centers, eight μ2-cyanides and two tetradentate cis-btmb ligands. Complex 2 is a ladder-like coordination polymer assembled by CuCN linear chain and bidentate trans-btmb linker. Complex 3 has a 2D wave-like network constructing from CuCN zigzag chain and V-shape dpa spacer. These coordination polymers are thermally stable up to 270–300 °C. They emit blue luminescence originating from ligand-centered emission.

Solvothermal reaction of CuCl 2 ·2H 2 O and 2-(4-pyridyl)benzimidazole (PyHBIm) in a acetonitrile-water mixed solvent afforded a mixture of [Cu I 2 Cu II (CN) 2 (PyHBIm) 2 Cl 2 ] n ( 1 ) and [Cu II (PyH 2 BIm) 2 Cl 4 ] ( 2 ). Complex 1 is a mixed-valence 1D ribbon Cu(I,II)-cyanide coordination polymer. One Cu(II) center linearly links two Cu(I) ions via two μ 2 -CN bridges. XPS spectrum and bond valence sum (BVS) analysis have confirmed the mixed-valence characteristics. Cu(II) ion adopts a centrosymmetric square-planar geometry surrounded by two cyanides and two pyridyl groups. Cu(I) ions adopt a trigonal geometry coordinated by cyanide, imidazole group and Cl − anion. The cyanide ligand is in situ generated from the cleavage of acetonitrile solvent, which indicates that acetonitrile is an environmentally friend cyanating agent. The mechanism of acetonitrile in situ cleavage under solvothermal condition is explained. Complex 2 is a centrosymmetric mononuclear Cu(II) compound. Four equivalent Cl − anions lie on the equatorial plane. The protonated PyH 2 BIm + cation as a monodentate ligand coordinates to Cu(II) center via pyridyl terminal.

A 4s-3d-4f heterometallic compound with the formula: [KNi4GdL4(H2O)8]·14·5H2O (1) was obtained by self-assembly of nickel nitrate and gadolinium nitrate with 2,2′-phosphinico-dibenzoic acid (H3L) under hydrothermal condition. Meanwhile, the molecular structure was confirmed by single-crystal X-ray diffraction analysis, IR and EA. The compound composes of a 3D framework based on Ni4Gd nodes and 2,2′-phosphinico-dibenzoate ligand. Interestingly, the {Ni4Gd} node exhibits a metal tetrahedron with Gd(III) ion locked in it. The pentanuclear {Ni4Gd} tetrahedra are further connected by double carboxylate groups resulting a zig-zag chain along b-axis. Moreover, the neighboring chains are bridged by potassium ions with water molecules to form a 3D framework. Variable-temperature magnetic susceptibility studies indicate that ferromagnetic interactions occur between the Ni(II) and Gd(III) ions.

Two novel one-dimensional complexes [Cu(H2O)2Fe(L)]·2H2O·CH3OH (1) and [Cu(H2O)2Fe(L)]·1.5H2O (2) were synthesized with stable Fe(IV) building block and copper ions as starting materials. The structures of the two complexes were well characterized by single crystal X-ray diffraction, elemental analysis, IR spectroscopic and thermal analyses. Both complexes present of a different 1D chain structure in which the tetravalent iron block performed totally different coordination modes. Magnetic studies indicate that both complexes exhibit a typical antiferromagnetic behavior.

Two novel coordination polymers {(MV)[M3(dca)8]}n (MV2+ = methylviologen dication, dca = dicyanamide anion, M = Co (1) and Ni (2)) have been synthesized by the reactions of methylviologen dichloride and sodium dicyanamide with cobalt(II) or nickel(II) ions. Their structures have been determined by single-crystal X-ray diffraction analysis and further characterized by elemental analysis, infrared spectra, and thermogravimetric analytical techniques. Compounds 1 and 2 are isomers, and crystallize in a centrosymmetric P21/n space group. In the structures of 1 and 2, the metal ions are attached through the µ1,3,5- dicyanamide groups generating a 2D sheet in bc plane. Furthermore, the neighbouring sheets are supported by the strut µ1,5-dca ligands into a 3D framework with open channels occupied by MV2+ cations. Magnetic studies indicate that, compound 1 exhibits antiferrimagnetic coupling between cobalt(II) ions, whereas ferromagnetic interaction was occurred between nickel(II) ions in compound 2.

Two new compounds, {[Cu2(tza)3(4,4′-bipy)2(H2O)](ClO4)(H2O)}n (1) and {[Cu2(4,4′-bipy)2(C2O4)(H2O)2](ClO4)2}n (2) were synthesized and structurally characterized. Compound 1 shows a 2D layered structure, which ultimately stacked by ABAB repeat pattern. Compound 2 features a three-fold interpenetrating 3D structure with 3-connected ths network. An interesting phenomenon has been found that tetrazole-1-acetic acid in situ generated oxalate ligand during the syntheses of compound 2.

MnII and CoII salts reacting with 4-(4-carboxyphenyl)-4,2′:6′,4″-terpyridine (4-Hcptpy) in DMF/H2O afford two complexes, [Mn(4-cptpy)(DMF)(H2O)2]n·n(4-cptpy)·nDMF (1) and [Co(4-cptpy)2(H2O)2]n (2). Complex 1 is a 1D ribbon coordination polymer assembled by Mn2 dimer and tridentate 4-cptpy ligand. The guest 4-cptpy anion is embedded in 3D supramolecular architecture with strong hydrogen bonds. Complex 2 is a 1D linear chain coordination polymer with quadrangled pores. The complex 1 releases H2O and DMF in 87–150 °C, and the anhydrous [Mn(4-cptpy)]n·n(4-cptpy) remains thermally stable until 403 °C. Variable temperature magnetic susceptibility study in 2–300 K proves that a weak antiferromagnetic interaction exists in the (μ-O2CR)2Mn2 core.

On the basis of triangular-shaped [Mn3O] secondary building units, a novel two-dimensional (2D) manganese(III) complex, [NaMnIII3O(sao)3(btec)0.5(H2O)3]·1.25H2O (1) (H2sao = salicylaldoxime, H4btec = benzene-1,2,4,5-tetracarboxylate acid), was synthesized and structurally characterized. The structure of 1 consists of 2D coordination polymer based on [Mn3O] units bridged by sodium ions and benzene-1,2,4,5-tetracarboxylate groups. Magnetic data analysis shows that antiferromagnetic couplings exist between the manganese(III) ions in [Mn3O] subunit of complex 1.

Two novel three-dimensional (3D) coordination polymers [ Cu 3 II ( mtta ) 6 ] n (1) and [ Cu 2 II Cu 3 I ( trz ) 4 Br 3 ] n ·nH2O (2) (mtta = 5-methyltetrazolate, trz = 1,2,4-triazole) were synthesized and structurally characterized. Complex 1 shows a 3D porous metal–organic framework. By the topology analysis, the complicated architecture of 1 can be simplified to be the 4-connected diamond-type net. Compound 2 is a two-fold interpenetrating 3,5-connected 3D framework with new topology.

Hydrothermal reactions of Cu(NO3)2 with 2,6-bis(1,2,4-triazolyl)pyridine (btp) and 1,3,5-benzenetricarboxylic acid (H3btc) or 1,2,4,5-benzenetetracarboxylic acid (H4btec) in base aqueous solution afford two novel complexes [Cu2(btp)(btc)(H2O)(OH)]n (1) and [Cu2(btp)(Hbtec)]n · nH2O (2). Complex 1 is a coordination polymer where a carboxylate and a hydroxyl are bound to Cu(II) ions to form (μ-OH)(μ-O2CR)Cu2 core, which is ferromagnetic couple with 2 J = 21.30 cm−1. Complex 2 is a 3-D coordination polymer. Bond valence sum (BVS) analysis indicates it is a mixed-valence compound. Cu(I) is three-coordinated by triazole N-donors, while Cu(II) is four-coordinated by a triazole N and three carboxyl O-donors. Both complexes are quite thermal stable.

An octacyanotungstate(V)-manganese(II) bimetallic assembly [Mn(Me2-bipy)2]3[W(CN)8]2·9H2O (1) (Me2-bipy = 4,4′-dimethyl-2,2′-bipyridine) was synthesized in methanol and characterized by X-ray crystallography. X-ray analysis shows that complex 1 is a neutral, one-dimensional (1D) infinite chain polymer. Magnetic data analysis demonstrates a long-range magnetic interaction and two different antiferromagnetic coupling constants obtained by fitting between Mn and W ions in 1.