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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. [ABSTRACT FROM AUTHOR]

Solvothermal reactions of mixed ligands H3BTC and macrocyclic oxamide complexes (ML, M = Cu, Ni) with M(ClO4)2·6H2O (M = Co, Zn, Ni and Cd) afford six new complexes, including [M′4(BTC)2(ML)2(OH)2(H2O)2]·2H2O (M′ = Co, M = Ni, for (1); M′ = Zn, M = Ni, for (2); M′ = Zn, M = Cu, for (3)), [Ni3(BTC)2(NiL)2(H2O)6]·2CH3OH·2H2O (4), [Cd4(BTC)2(HBTC)(NiL)4(H2O)]·3H2O (5) and [Cd(HBTC)(CuL)]·H2O (6) (ML, H2L = 2, 3-dioxo-5, 6, 14, 15-dibenzo-1,4,8,12-tetraazacyclo-pentadeca-7,13-dien; H3BTC = 1,3,5-benzenetricarboxylic acid). Complexes 1–3consist of a 2D layer framework formed by the linkage of M(ii)(M = Ni, Cu) and M′4(M′ = Co, Zn) cluster viathe oxamide and BTC3−bridges and display a (3,6)-connected network with a (43)2(46.66.83) topology. The structure of 4consists of pentanuclear [NiII5] units and arranges in a 1D cluster chain. Complex 5exhibits a 2D layered structure characterized by 3,4,3-connected (4.62)3(4.63.82)(42.63.8)(42.6) topology. Complex 6possesses a 3D network with sratopology. The magnetic properties of complexes 1and 4were investigated. [ABSTRACT FROM AUTHOR]

Abstract: Two novel coordination polymers, [Cu(PDCO)·(H2O)] n (1) and [Cd(PDCO)(bipy)·(H2O)·5H2O] n (2), (H2PDCO=pyridine-3,5-dicarboxylic acid N-oxide, bipy=4,4′-bipyridine), have been synthesized under hydrothermal conditions, and their structures were determined by single-crystal X-ray diffraction studies. Polymer 1 features a three-dimensional (3D) network with nonequivalent nodes of (63)2(69 ·85 ·10) topology. Polymer 2 exhibits one-dimensional (1D) double-stranded chains. The magnetic character of 1 as well as the gas adsorption and luminescent properties of 2 have been investigated. [Copyright &y& Elsevier]

Abstract: Six new coordination polymers, [Co(NiL)(aipt)] (1), [Co2(ML)(hipt)2(CH3OH)(H2O)]·CH3OH (M=Cu (2), Ni (3)), [Co2(C2O4)2(CuL)2] (4), [Co4(NiL)4(ipt)4(H2O)2] (5) and [Co(CuL)(tpt)] (6) (H2L=2,3-dioxo-5,6,14,15-dibenzo-1,4,8,12-tetraazacyclo-pentadeca-7,13-dien; H2aipt=5-aminoisophthalic acid; H2hipt=5-hydroxyisophthalic acid; H2ipt=isophthalic acid; H2tpt=terephthalic acid), have been synthesized by a solvothermal method and characterized by single-crystal X-ray diffraction. Complexes 1, 4 and 5 exhibit different infinite chain structures formed by CoNi (1), Co2Cu2 (4), Co4Ni4 (5) units, respectively, via oxamide and diverse carboxylate bridges, while complexes 2, 3 and 6 exhibit different two-dimensional network structures formed by Co2M or Co2M2 units via oxamide and 5-hydroxyisophthalate or terephthalate bridges. The results of magnetic determination show weak antiferromagnetic interactions in 1–3 and 5–6, and the spin–orbit coupling interaction of Co(II) is a primary factor in the magnetic behaviors. [Copyright &y& Elsevier]

A series of 3d-4f heterometallic coordination polymers (CPs), namely, Ln 2 (CuL) 2 (nipt) 3 (H 2 O)]⋅nH 2 O (Ln = Sm 1 , Nd 2 , Gd 3 , for 1 – 2 n = 2, for 3 n = 1.6), [Yb 2(CuL) 4 (nipt) 3 ]·3.5H 2 O (4), [Pr 2 (NiL)(nipt) 3 (H 2 O)]⋅1.5H 2 O (5), [Sm 2 (NiL)(nipt) 3 (H 2 O) 2 ]CH 3 OH⋅H 2 O (6), [Er 2 (NiL) 2 (nipt) 3 (H 2 O) 2 ]⋅3H 2 O (7) (ML, H 2 L = 2, 3-dioxo-5, 6, 14, 15-dibenzo-1, 4, 8, 12-tetraazacyclo-pentadeca-7, 13-dien; H 2 nipt = 5-nitroisophthalic acid) were obtained by a solvothermal method and structurally characterized. Complexes 1–3 have 3,3,4,5-connected (3.4.5)(32.42.5.63.72)(42.63.8)(42.6) topological structure consisting of two different chains. 4 exhibits a two-dimensional (2D) heterometallic structure with 3-connected (63) topology. 5 displays a 2D framework formed by four-strand meso-helical chains and characterized by 6,6,4,4,4-connected (411.64)(412.63)(43.62.8)(45.6) 2 topology. Compound 6 has 3,4,4,3-connected (43)(44.62)(42.124)(42.6) topological structure formed by three-strand meso-helical chains. In 7 , two kinds of μ 3 -bridged nipt2− ligands together with NiL connect the eight-coordinated Er3+ ions to form a 2D structure, and the 2D layers are extended by μ 2 -bridged nipt2− into a three-dimensional (3D) microporous framework with 4,4,3,3-connected (4.62.83) 2 (4.82) 2 topology. Interestingly, for 1 , 2 and 4 , CuL-sensitized the near-infrared emissions form Sm(III), Nd(III) and Yb(III) were firstly found under visible light irradiation. Moreover, the magnetic properties of 1 , 2 , 4 and 5 are also discussed. Image 1 [ABSTRACT FROM AUTHOR]

Seven new 3d–4f heterometallic coordination polymers, [Ln(CuL) 2 (Hbtca)(btca)(H 2 O)]·2H 2 O (Ln = Tb III 1 , Pr III 2 , Sm III 3 , Eu III 4 , Yb III 5 ), [Nd(NiL)(nip)(Rnip)]·0·25H 2 O·0.25CH 3 OH (R= 0.6CH 3 , 0.4H) 6 and [Nd 2 (NiL)(nip) 3 (H 2 O)]·2H 2 O 7 (CuL or NiL, H 2 L = 2, 3-dioxo-5, 6, 14, 15-dibenzo-1, 4, 8, 12-tetraazacyclo-pentadeca-7, 13-dien; H 2 btca = benzotriazole-5-carboxylic acid; H 2 nip = 5-nitroisophthalic acid) have been synthesized by a solvothermal method and characterized by single-crystal X-ray diffraction. Complexes 1–5 exhibit a double-strand meso-helical chain structures formed by [Ln III Cu II 2 ] units via the oxamide and benzotriazole-5-carboxylate bridges, while complex 6 exhibits a four-strand meso-helical chain formed by NdNi unit via the oxamide and 5-nitroisophthalate bridges. Complex 7 consists of a 2D layer framework formed by four-strand meso-helical chain via the nip 2− bridges. Moreover, the magnetic properties of them were investigated, and the best-fit analysis of χ M T versus T show that the anisotropic contribution of Ln(III) ions (arising from the spin-orbit coupling or the crystal field perturbation) dominates (weak exchange limit) in these complexes(for 3 , λ = 214.6 cm −1 , zj’ = −0.33 cm −1 , g av = 1.94; for 5 , Δ = 6.98 cm −1 , zj’ = 1.53 cm −1 , g av = 1.85). [ABSTRACT FROM AUTHOR]

Two novel two-dimensional copper–nitroxide coordination polymers of formula [Cu2(NIT3Py)2(glu)2]n (1) and {[Cu2(NIT3Py)2(adip)2]·CH3OH·0.5H2O}n (2) (NIT3Py=2-(3′-pyridyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide, H2glu=glutaric acid and H2adip=adipic acid), have been synthesized and characterized structurally as well as magnetically. The crystal structures of both polymers contain the paddle-wheel binuclear Cu(II) units axially coordinated by NIT3Py ligands which are bridged by the flexible glutarate or adipate anions into the corrugated 2D sheets. Interestingly, complex 1 displays a 2D helical layer structure rarely found in metal–nitroxide systems. The magnetic measurements show the strong antiferromagnetic interactions in the binuclear Cu(II) units and weak antiferromagnetic interactions between copper ions and nitroxides. [ABSTRACT FROM AUTHOR]