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A series of nine mixed-ligand metal-organic frameworks (MOFs) have been prepared by the combination of a bent dipyridyl linker 4-amino-3,5-bis(4-pyridyl)-1,2,4-triazole (bpt) and three benzenedicarboxylate isomers (pa = phthalate, ip = isophthalate, and tp = terephthalate), respectively, with different metal ions such as CoII, NiII, CuII, ZnII, and CoII. The framework structures of these neutral polymeric complexes have been determined by the X-ray single- crystal diffraction technique. Structural analysis reveals that the benzenedicarboxylate isomers display versatile coordination modes to manage the metal ions to form 1-D chain or ribbon arrays, which are further extended via the exo-bidentate bpt connectors to give rise to a variety of coordination networks, such as a simple (4,4) layer, 2-D double layer with decorated (4,4) topology, 2-D layer with decorated (3,6) topology, 2-D bilayer with 8².10 topology (2-fold interpenetration), 3-D polythreaded architecture (1-D + 2-D), and 2-fold interpenetrating porous lattice of (4,4) layers. The accessorial secondary interactions such as hydrogen bonding and/or aromatic stacking are also helpful for the extension and stabilization of the final supramolecular aggregates. This work evidently indicates that the isomeric effect of the anionic benzenedicarboxylate is significant in the construction of these network structures, which are also well regulated by the metal centers. The ZnII and CdII MOFs exhibit strong solid-state luminescence emissions at room temperature, which originate differently from intraligand transition or ligand-to-metal charge transfer. Thermal stability of these crystalline materials has been explored by thermogravimetric analysis of mass loss. The 3-D host frameworks of MOFs 8 and 9 show similar porous cavities, and their desorption/ adsorption behaviors of guest solvents have also been investigated. [ABSTRACT FROM AUTHOR]

The formation, crystal structures, and properties of a series of three-dimensional (3-D) CuII coordination polymers, {[Cu(L)2(H2O)2](PF6)2(H2O)1.25}n (1), {[CuL(N3)2](H2O)1.5}n (2), and {[CuL(H2O)(SO4)](H2O)2}n (3), with an angular bridging ligand 2,5-bis(4-pyridyl)-1,3,4-oxadiazole (L) are reported. Complex 1 crystallizes in the tetragonal /41/a space group (a = b = 13.462(2) Å, c = 46.47(1) Å, Z = 8), complex 2 in the orthorhombic Pna21 space group (a = 6.379(2) Å, b = 10.060(3) Å, c = 27.232(9) A, Z = 4), and complex 3 in the orthorhombic P212121 space group (a = 5.510(2) Å, b = 10.576(4) ,Å, c = 28.34(1) Å, Z = 4). Different polymeric frameworks are obtained by only varying the counterions. These include the 2-fold interpenetrated diamondoid structure of 1, the acentric α-Po network of 2, and the chiral open framework of 3 with (6³).(69.8) topology. The interesting anion-exchange, porous, and magnetic properties of these coordination supramolecules have been investigated in detail. [ABSTRACT FROM AUTHOR]

Examines the crystal structure with three-dimensional coordination of polymer with angular dipyridyl ligand. Discussion on the magnetic properties and anion effects; Degree of interpenetration of diamondoid networks; Integration of diffraction profiles.

Investigates the varying coordination modes and magnetic properties of copper(II) complexes with diazamesocyclic ligands by altering additional donor pendants on 1,5-diazacyclooctane. Syntheses of ligands; Description of the crystal structures; Binuclear, trinuclear and polymeric complexes; Electronic spectra.

The reaction of copper(II) nitrate, oxamide, and an angular bridging ligand 2,5-bis(4-pyridyl)-1,3,4-oxadiazole (4-bpo) under hydrothermal conditions affords a 3D pillared-layer coordination framework {[Cu2(4-bpo)(ox)2](H2O)4}n (1) (ox = oxalate), featuring the unique zeolite-type NiP2 network and interesting properties. [ABSTRACT FROM AUTHOR]

Six new metal-organic coordination networks based on linking unit 2,5-bis(4-pyridyl)-l,3,4-thiadiazole (L¹) or 2,5bis(3-pyridyl)-l,3,4-oxadiazole (L³) and inorganic CuΙΙ CdΙΙ, and CoΙΙ salts have been prepared and structurally characterized by single-crystal X-ray analysis. Using L¹ to react with three different CuΙΙsalts, Cu(OAc)2·H2O, Cu(NO3)2·3H2O, and CuSO4·5H20, respectively, two different one-dimensional (l-D) coordination polymers, {[Cu2L¹(μOAc)4](CHCI3)2}n (1) [triclinic, space group P1macr;, a = 7.416(3) Å, b = 8.207(3) Å, c = 14.137(5) Å, α = 100.333(7)°, β = 105.013(6)°, γ = 94.547(6)°, Z = 1] and {[CuL¹(NO3)2](CHCI3)0.5}n (2)[monoclinic, space group C2/c, a = 28.070(8) Å, b = 9.289(3) Å, c= 15.235(4) Å, β = 113.537(5)°, Z = 8], and a chiral 3-D open framework, {[CuL¹(H2O)(SO4)](H20)2}n (3)[orthorhombic, space group P212121, a = 5.509(2), Å b = 10.545(4) Å, c = 29.399(11) Å, Z = 4], were obtained. Reaction of L¹ and Cd(ClO4)2·6H2O or Co(ClO4)2·6H2O, in the presence of NH4SCN, yielded another 3-D open framework, {[CdL¹(NCS)2](CH3OH) 1,5}n (4) [monoclinic, space group C2/c, a = 28.408(10) Å, b = 9.997(5) Å, c = 7.358(4) Å, β = 99.013(8)°, Z= 4], or a 2-D network, {[Co(L¹)2 (NCS) 2](H2O)2.5}n (5) [orthorhombic, space group Pnna, a = 22.210(5) Å, b = 12.899(3) Å, c = 20.232(4) Å, Z = 4]. When L¹ was replaced by L³ to react with Co(CIO4)2·6H20 and NH4SCN, another 2-D coordination polymer, [Co(L³)2(NCS)2]n (6) [monoclinic, space group P21/c, a = 8.120(3) Å, b = 9.829(4) Å, c = 17.453(6) Å, β = 103.307(6)°, Z = 2], was constructed. These results indicate that the nature of the ligands, metal centers, or counteranions plays the critical role in construction of these novel coordination polymers. The interesting porous natures of two 3-D open frameworks 3 and 4 were investigated by TGA and XPRD techniques, and the magnetic properties of the CuΙΙ and CoΙΙ complexes were studied by variable-temperature magnetic susceptibility and magnetization measurements. [ABSTRACT FROM AUTHOR]

Examines the features of metal complexes with a flexible bis(sulfinyl). Propensity to form multidimensional coordination polymers with transition metals and rare earth elements; Preference for O-binding in hard acid metal complexes; Ability of the ligands to form diverse extended networks.

Examines the crystallography and photophysical and electrochemical properties of dinuclear or chain polymeric silver(I) complexes with polypyridyl bridging ligands by cyclic voltammetry and emission and electronic absorption spectra. Bond lengths and angles; Thermal ellipsoid at 30% probability.

A new pillared-layer coordination polymer, [Co3(pybz)2(pico)2]n (1; pybz = 4-(pyridin-4-yl)benzoate, pico = 3-hydro- xypicolinate), contains rare 2D [Co3(pico)2]n2n+ layers formed by linear cobalt(ll) tnmers through the unusual μ4∙KN, O:KO'-μ2:KO"-μ2 bridging mode of pico ligands, which are further cross-pillared by exotridentate bridging pybz ligands to form a three-dimensional structure with an unusual uninodal 8-connected body-centered-cubic topology. The bulk magnetic behavior of 1 exhibits ferrimagnetic long-range ordering below 2.6 K, which mainly arises from the cooperative magnetic effect of the intra- and intertrimer arrangements in the 20 magnetic system based on the nature of the exchange modes of μ2-hydroxyl, μ2-carboxylate oxygen, and 1,1 ,3-μ3-carboxylate bridges. [ABSTRACT FROM AUTHOR]