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Two heterometallic 3d–4f coordination polymers, [Gd(CuL)2(Hbtca)(btca)(H2O)]·2H2O (1) and [Er(CuL)2(Hbtca)(btca)(H2O)]·H2O·CH3OH (2) (CuL, H2L = 2,3-dioxo-5,6,14,15-dibenzo-1,4,8,12-tetraazacyclo-pentadeca-7,13-dien; H2btca = benzotriazole-5-carboxylic acid) were synthesized by solvothermal methods and characterized by single-crystal X-ray diffraction. Complexes 1 and 2 exhibit a double-strand meso-helical chain structures formed by [LnIIICuII2] (LnIII = Gd, Er) units by oxamide and benzotriazole-5-carboxylate bridges. They are isomorphic except that one free water molecule of 1 is replaced by a methanol molecule. All 1D chains are further interlinked by hydrogen bonds resulting in a 3D supramolecular architecture. The magnetic properties of the compound 1 and 2 are also discussed.

Three coordination polymers [Pb2(nipt)2(NiL)2] (1), [Pb(tpt)(NiL)]·2H2O (2), and [Pb2(ipt)2(NiL)2] (3) (ML, H2L = 2, 3-dioxo-5, 6, 14, 15-dibenzo-1, 4, 8, 12-tetraazacyclo-pentadeca-7, 13-dien, H2nipt = 5-nitroisophthalic acid, H2tpt = terephthalic acid, H2ipt = isophthalic acid) were synthesized by solvothermal methods and characterized by single-crystal X-ray diffraction. Complex 1 exhibits a zigzag chain consisting of Pb2Ni2 units with oxamide and 5-nitro isophthalate bridges, whereas complex 2 possesses a double chain with oxamide and terephthalate bridges. Complexes 1 and 2 have a 2D supramolecular architecture formed by intermolecular interactions and hydrogen bonds. Complex 3 exhibits a two-dimensional network structures formed by Pb4Ni4 units via oxamide and isophthalate bridges. In complexes 1–3, the arrangement of donor atoms suggest that the coordination around the lead(II) atoms is hemi-directed. The different steric hindrance of bridged ligands, and lone pair electrons effect of lead(II) ion cooperatively influence nipt, tpt and ipt displaying in diverse connecting modes and further result in different structures. Additionally the fluorescence properties of compounds 1–3 are discussed.

Three two-dimensional coordination polymers {[Zn(H-3, 3-bpma)(1, 2,4-btc)]·H2O}n (1), {[Cu2(H-3, 3-bpma)2(1, 2,4-btc)(H-1, 2,4-btc)(H2O)2]·ClO4·7.75H2O}n (2), and {[Cd4(H-3, 3-bpma)2(1, 3,5-btc)3Cl(H2O)7]·12.75H2O}n (3) [3, 3-bpma = N,N′-bis(3-pyridylmethyl)amine, H3-1, 2,4-btc = 1, 2,4-benzenetricarboxylic acid, and H3-1, 3,5-btc = 1, 3,5-benzenetricarboxylic acid] were synthesized and characterized by X-ray crystallography. The complexes are all two-dimensional layer networks with diverse topologies bridged by mixed flexible bis(pyridylmethyl)amine and auxiliary rigid aromatic multicarboxylate ligands. The H-3, 3-bpma ligands adopt different conformations, whereas the aromatic multicarboxylates show various binding modes in the complexes. The magnetic, photoluminescence and thermal properties for complexes 1 and 2 were investigated.

Two coordination polymers [Zn2(ipt)2(CuL)2(H2O)] (1) and [Zn2(ipt)2(NiL)2(H2O)] (2) (ML, H2L = 2,3-dioxo-5,6,14,15-dibenzo-1,4,8,12-tetraazacyclo-pentadeca-7,13-dien; H2ipt = isophthalic acid) were synthesized by solvothermal methods and characterized by single-crystal X-ray diffraction. Complexes 1 and 2 exhibit ladderlike chains, consisting of Zn4Cu4 and Zn4Ni4 units, respectively, which are connected via oxamide and isophthalate. These chains are further interlinked by hydrogen bonds resulting in a 2D supramolecular architecture. The fluorescence properties of compounds 1 and 2 are also discussed.

Three new one-dimensional (1D) chain metal–nitroxide complexes {[Cu(NIT4Py)2(suc)(H2O)]·3H2O}n (1), {[Cd(NIT4Py)2(suc)(H2O)]·[Cd(NIT4Py)2(suc)(H2O)2]·3H2O}n (2), and {[Zn(NIT4Py)(glu)(H2O)]·H2O}n (3) [NIT4Py = 2-(4′-pyridyl)-4, 4, 5, 5-tetramethylimidazoline-1-oxyl-3-oxide, suc = succinate anion and glu = glutarate anion] were synthesized and structurally characterized. Single-crystal X-ray analyses indicate that the three complexes crystallize in neutral 1D chains in which the metal-nitroxide units are linked by flexible dicarboxylate anions. The succinate anions only adopt trans configuration in complexes 1 and 2, whereas the glutarate anion has gauche/anti conformation in complex 3. Magnetic measurements show that complex 1 exhibits weak antiferromagnetic interactions between the copper ions and the nitroxides.

Three new complexes [Cu(Hbpma)(ox)Cl]2·8H2O (1), {[Co2(bpma)(ox)2(H2O)2]·6H2O}n (2), and {[Zn2(bpma)(ox)2(H2O)2]·6H2O}n (3) (bpma = N,N′-bis(3-pyridylmethyl)amine and ox = oxalate) were synthesized and structurally characterized by single-crystal X-ray diffraction. Complex 1 is a bpma-bridged dinuclear CuII compound, whereas the oxalate only acts as terminal ligand by bidentate chelating mode. Complexes 2 and 3 are isomorphs found to be one-dimensional coordination polymers bridged by both bpma and ox ligands. The conformation of bpma ligand has a transformation from trans-gauche mode in complex 1 to trans-trans one in complexes 2 and 3. The magnetic property of complex 2 shows the occurrence of antiferromagnetic interactions between two adjacent CoII ions.

Three novel complexes, namely [Zn(CuL)(pzdc)]2·5H2O (1), [Zn(NiL)(pzdc)]2·5H2O (2), and [Gd2(pzdc)2(NiL)6](ClO4)2·6H2O (3) (CuL and NiL, H2L = 2, 3-dioxo-5, 6, 14, 15-dibenzo-1, 4, 8, 12-tetraazacyclo-pentadeca-7, 13-dien and H2pzdc = pyrazine-2, 3-dicarboxylic acid) were synthesized and structurally determined. Complexes 1 and 2 are tetranuclear [ZnII2MII2] (M = Ni (1), Cu (2), respectively) molecules including both oxamide and pzdc2– bridges. The structure of compound 3 consists of pyrazine-2, 3-dicarboxylate and oxamido-bridged, and is arranged in different butterfly-like octanuclear molecules. The magnetic susceptibility data of 3 were analyzed.

Two new dithioether ligands, 1,4-bis[(phenylsulfanyl)methyl]naphthalene (L1), and 4,4′-bis[(tert-butylsulfanyl)methyl]biphenyl (L2) were synthesized and their silver(I) complexes were studied. Both AgI complexes, [AgL1(NO3)]n (1) and [AgL2(NO3)]2 (2), were synthesized at ambient temperature and characterized by elemental analysis, IR spectroscopy, and single-crystal X-ray diffraction analysis. Single-crystal X-ray analysis shows that complex 1 has a one-dimensional helical chain structure with the neutral repeating unit [Ag(μ2-L1)(NO3)], whereas complex 2 has a centrosymmetrical neutral dinuclear structure. Moreover, complexes 1 and 2 are further extended into three-dimensional supramolecular frameworks by hydrogen bonding and π–π stacking interactions, respectively. In addition, complexes 1 and 2 display strong blue emission in the solid state at room temperature.

Two heterometallic trinuclear complexes of macrocyclic oxamide [Co(NiL1)2L2(H2O)]·3H2O (1) and [Mn(NiL1)2L2(H2O)]·0.5CH3OH·1.5H2O (2) (H2L1 = 2,3-dioxo-5,6,14,15-dibenzo-1,4,8,12-tetraazacyclopentadeca-7,13-diene, H2L2 = 5-sulfosalicylic acid) were synthesized and structurally characterized by elemental analysis, IR spectroscopy, and X-ray diffraction. Single-crystal X-ray analyses reveal that both the complexes contain discrete neutral trinuclear [(NiL1)2ML2(H2O)] (for 1 and 2, M = Co, Mn, respectively) moieties. The structures of 1 and 2 have oxamido-bridged trinuclear [MIINiII2] units and consist of one-dimensional chains formed by strong intermolecular hydrogen bonds. Furthermore, the magnetic properties of complex 1 were investigated and discussed in detail.

Two novel heteronuclear complexes [Cd3(SSAL)2(CuL)2(H2O)4]n (1) and [Cd2(HSSAL)2(NiL)4]·4H2O (2) were synthesized and structurally determined, where SSAL is the fully deprotonated 5-sulfosalicylic ion (CuL and NiL, H2L = 2,3-dioxo-5,6,14,15-dibenzo-1,4,8,12-tetraazacyclopentadeca-7,13-diene). Compound 1 displays a 1D ladder-like chain and all these chains are further interlinked through hydrogen bonds resulting in a 2D architecture. The structure of 2 consists of 5-sulfosalicylates and an oxamido-bridge and is arranged in butterfly-like hexanuclear molecules. The luminescent properties of compounds 1 and 2 are also discussed.

Two one-dimensional (1-D) chain manganese-nitroxide complexes {[Mn(NIT4Py)2(ip)(H2O)2]·4H2O}n (1) and [Mn(IM4Py)2(ip)(H2O)2]n (2) (NIT4Py = 2-(4′-pyridinyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide, IM4Py = 2-(4′-pyridinyl)-4,4,5,5-tetramethylimidazoline-1-oxyl and ip = isophthalate anion) have been synthesized and characterized by elemental analyses, IR spectrum and electronic absorption spectra. Complex 1 was structurally characterized and it crystallizes in neutral 1-D chains where MnII nitroxide units [Mn(NIT4Py)2(H2O)2] are linked by isophthalate anions. The magnetic measurements show that complex 1 exhibits antiferromagnetic couplings, while complex 2 exhibits ferromagnetic interactions between the MnII ion and the nitroxide radicals.

A new coordination polymer of the formula [Ni(NIT4py)2(ip)(H2O)]n(NIT4py = 2-(4′-pyridinyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide and ip = isophthalate dianion) has been synthesized and characterized by elemental analyses, IR spectrum, and single-crystal X-ray diffraction. The coordination about each Ni2+ ion is a distorted octahedra. Each isophthalate dianion binds two Ni2+ ions in monodentate-bidentate mode, leading to a 1-D chain. Among the chains, the coordinated water molecules and carboxylato oxygen atoms form hydrogen bonds, generating an infinite 1-D ladder structure of a double-chain. The magnetic study shows that the decrease of χMT value in the low temperature for the complex is mainly ascribed to the zero-field splitting of the distorted octahedral Ni2+ ions.

Two diamagnetic-metal nitronyl nitroxide radical complexes with dicyanoargentate(I) bridges M(NIT4Py)2[Ag(CN)2]2 (M= Zn, Cd) were synthesized. X-ray crystallography reveals that the two compounds are isomorphous, which crystallize in the triclinic space group. Their structures consist of infinite chains of M(NIT4Py)2 units linked by [Ag(CN)2]−μ2-bridging ligands. The magnetic measurements showed that the χMT values are nearly constants at higher temperature for both complexes. The sharp decreasing of χMT values at lower temperature are related to intermolecular antiferromagnetic interactions, which result from the shortest interchain contacts of nitroxide groups in the crystals.

The two complexes of formula [Cu2(CuL)2(μ-N3)4]·2CH3OH (1) and [Cu2(NiL)2(μ-N3)4]·2CH3OH (2) (CuL and NiL, H2L = 2,3-dioxo-5,6,14,15-dibenzo-1,4,8,12-tetraazacyclo-pentadeca-7,13-dien), were synthesized and structurally determined. The magnetic susceptibility data of 1 and 2 were analyzed. For complex 1, magnetic measurements show alternating ferromagnetic and antiferromagnetic exchange couplings J1 = 23.67 cm–1, J2 = –189.11 cm–1, zJ’ = –0.62 cm–1. For complex 2, the doubly bridged asymmetric EO promotes a ferromagnetic interaction between CuII and CuII ions(J = 40.764 cm–1).