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A novel cadmium metal-organic coordination polymer, namely Cd(atda)(3-abpt)(H2O)·2H2O (H2atda = (4-amino-1,2,4-triazole-3,5-diyldithio) diacetic acid, 3-abpt = 4-amino-3,5-bis(3-pyridyl)-1,2,4-triazole)), has been obtained under hydrothermal conditions by the reaction of cadmium salts with two kinds of organic ligands, characterized by single-crystal X-ray diffraction analysis, elemental analysis, and thermogravimetric analysis. Structural analysis reveals that complex possesses a 2D honeycomb network. Additionally, the complex show strong fluorescence in solid state at room temperature. [ABSTRACT FROM AUTHOR]

Reactions of piperazine hexahydrate with triazol and paraformaldehyde afford a new piperazine-containing ligand: (N,N′-bis(1-H-1,2,4-triazole-1-yl)piperazine) (btp). X-ray crystal diffraction reveals that btp is an overall linear structure. Its Hg2+ polymer displays a zigzag chain in which piperazine is held in the chair conformation. In addition, the spectra properties of the btp and 1 are investigated, the strong luminescence characteristics of btp and 1 are found. [ABSTRACT FROM AUTHOR]

Two new complexes [Ni(phen)(H2O)4] · (atda)(H2O)5 (1) and [Ni2(4,4' -bipy)2(H2O)8] · (atda)2 (2) (where H2atda = (4-amino-1,2,4-triazole-3,5-diyldithio)diacetic acid, phen = 1,10-phenanthroline, 4,4' -bipy = 4,4' -bipyridine) have been synthesized and characterized by elemental analysis, IR, UV, thermogravimetric analysis and X-ray diffraction technique. X-ray structural analyses reveal that the two complexes are both three-dimensional (3D) supramolecular structures and possess similar structural characters. The Ni(II) centers are both in distorted octahedral coordination environments, six-coordinated by four water molecules and two nitrogen atoms from a 1,10-phenanthroline molecule or two 4,4' -bipyridine molecules. The atda2 - ligands do not coordinate to the Ni(II) centers, but only exist as counter anions, forming hydrogen bonds with coordinated or uncoordinated water molecules. Various hydrogen-bonding interactions play an important role in the assembly of three-dimensional supramolecular architectures. [ABSTRACT FROM AUTHOR]

Seven new metal-organic coordination polymers, [M(tzda)(H2O)4]n [M = Co(1), Ni (2) and Zn(3)], [Zn(tzda)(4,4'-bipy)]n (4), [Cd(tzda)(4,4'-bipy)0.5(H2O)]n (5) and [M(tzda)(4,4'-bipy)(H2O)]n [M = Co(6), Ni(7)] [H2tzda = (1,3,4-thiadiazole-2,5-diyldithio)diacetic acid, 4,4'-bipy = 4,4'-bipyridine] have been hydrothermally synthesized and structurally characterized by X-ray single crystal diffraction. Compounds 1-3 display similar 1D zigzag chain structure. Compound 4 possesses a 2D-layered architecture generated from [Zn(tzda)]n moiety with double-chain structure cross-linking 4,4'-bipy spacers, while compound 5 consists of -Cd-OCO-Cd-OCO- chains cross-linked through -CH2SC2N2SSCH2- spacers of tzda anions and 4,4'-bipy, also showing a 2D-layered structure. The structures of 6 and 7 seem more complicated, in which the [M(tzda)]n layered subunits are extended to unique 3D framework by the bridging 4,4'-bipy ligand. Photoluminescence investigations reveal that 4 and 5 both display strong blue emissions in the solid state at room temperature, which could be significant in the field of luminescent materials. The magnetic studies of 6 and 7 show both display the characteristics of a weak antiferromagnetic coupling between metal ions in the system mediated by carboxylate bridges. [ABSTRACT FROM AUTHOR]

A novel 3D coordination polymer [Mn(tzda)(4,4'-bipy)(H2O)]n (1) of mixed ligands, (1,3,4-thiadiazole-2,5-diyldithio)diacetic acid (H2tzda) and 4,4'-bipyridine, has been hydrothermally synthesized and characterized by single-crystal X-ray diffraction and IR spectra. Complex 1 crystallizes in the orthorhombic space group Pbca with a=18.1657(9)Å, b=9.0882(5)Å, c=22.9333(12)Å. In the structure, each Mn(II) ion is in a distorted octahedral coordination geometry, three among four coordination sites of the equatorial plane are occupied by the carboxylate oxygen atoms and the remaining site is occupied by the water molecule while the apical positions are occupied by two nitrogen atoms from two bipy molecules. The six-coordinated Mn ions are interlinked by flexible tzda ligands to form layers, which are sustained by rigid 4,4'-bipy ligands into a 3D open framework. The magnetic property of 1 was also investigated and the magnetic susceptibility data were rationally fitted with J=-0.103 cm-1, g=2.09, zJ'=-0.02 cm-1, showing weakly antiferromagnetic interactions among Mn(II) ions in 1. [ABSTRACT FROM AUTHOR]

A novel 3D coordination polymer [Gd2(tzda)3(H2O)5]n (1) has been synthesized by hydrothermal reaction of Gd(NO3)3 with a flexible building unit - (1,3,4-thiadiazole-2,5-diyldithio)diacetic acid (H2tzda). X-ray single crystal diffraction analysis reveals that 1 belongs to triclinic system, P1¯ space group. The crystallographic data are: a=9.6769(7)Å, b=13.4539(9) Å, c=14.9369 (10)Å, α=65.9050(10)°, β=82.1290(10)°, γ=80.1210(10)°. In the structure, two Gd(III) ions are both nine-coordinated and in different coordination environments while the tzda2- anions display three different coordination modes to link Gd(III) ions and then form a complicate three-dimensional network structure. [ABSTRACT FROM AUTHOR]

A new planar aromatic tridentate terpyridine-like ligand, 2,4- bis (3,5-dimethylpyrazol-1-yl)-6-diethylamino-1,3,5-triazine ( L ), has been synthesized and the structures of its complexes [Y L (NO 3 ) 3 ] ( 1 ) and [Ln L (NO 3 ) 3 (H 2 O)] L [Ln = La ( 2 ), Ce ( 3 ), Pr ( 4 ), Nd ( 5 ), Eu ( 6 )] have been determined by X-ray crystal structural analysis. The structures of the five lanthanoid complexes are isomorphous and isostructural but different from the crystal structure of the yttrium complex [Y L (NO 3 ) 3 ]. The latter shows a nine-coordinate metal center whereas the crystal structure of the lanthanoid complexes [Ln L (NO 3 ) 3 (H 2 O)] L show a 10-coordinate metal center. The π-π stacking and hydrogen bonding between the coordinated and uncoordinated L molecules sensitized the Ln luminescence. The thermal behavior of the ligand and its complexes is discussed. [ABSTRACT FROM AUTHOR]

Two novel coordination polymers, [Cu(ll)(NO[sub 3])[sub 2](bbmb)][sub n] (1) and [Mn(II)(C1[sub 2])(BBMB)[sub 2]] (2) [bbmb=1,4-bis(1-benzimidazolylmethyl)benzene], were synthesized and characterized by IR and thermal analyses. Single-crystal X-ray diffraction analysis shows that Polymer 1 exhibits a distorted metal tetrahedron in its structure, involving two nitrogen atoms from bbmb ligands and two oxygen atoms from NO[sub 3] groups. Each Cu(II)(NO[sub 3])[sub 3] unit is bridged by bbmb to form a zigzag chain structure. Polymer 2 possesses a two-dimensional network. The coordination environment around Mn(II) is a distorted octahedron and its solid-state structure exhibits a layered packing mode. In the polymers the two coordinating nitrogen atoms on bridging bbmb ligands are trans to the central benzene plane. [ABSTRACT FROM AUTHOR]

A novel ferrocenyl dimer [Zn 2 (μ-OOCFc) 4 (3-PyCOOCH 3 ) 2 ] (Fc=(η 5 -C 5 H 5 )Fe(η 5 -C 5 H 4 )), 1 , was obtained by the reaction of Zn(OAc) 2 ·2H 2 O with sodium ferrocenecarboxylate and 1,4-butanediol dinicotinate in methanol solution. X-ray structural analysis reveals that the compound contains two zinc(II) centers symmetrically bridged by four ferrocenecarboxylate anions as O,O′-bridging ligands, leading to a dimeric tetrabridged [Zn 2 (μ-OOCFc) 4 ] core. The zinc(II) ion is in a distorted octahedral environment with four oxygen atoms from four distinct ferrocenecarboxylates, a nitrogen atom from the ligand NC 5 H 4 CO 2 CH 3 , and another zinc atom. The symmetry of the complex in the paddle-wheel structure brings the metal centers close, the intradimer distance being 2.934(11) Å. It is the first example of a zinc(II) dimer with ferrocenecarboxylate anion ligands. Its thermal properties were measured in air. [ABSTRACT FROM AUTHOR]

Abstract: Five new transition metal coordination polymers based on H2tzda and co-ligand bpe, {[M(tzda)(bpe)]·H2O} n [M=Zn(1), Cd(2), Mn(3), Co(4)] and [Ni2(tzda)2(bpe)2(H2O)] n (5) [H2tzda=(1,3,4-thiadiazole-2,5-diyldithio)diacetic acid, bpe=1,2-bis(4-pyridyl)ethane], have been hydrothermally synthesized and structurally characterized. Compounds 1–4 feature a 2D-layered architecture generated from [M(tzda)] n moiety with double-chain structure cross-linking bpe spacers. However, the conformations bpe adopts in 3 and 4 are different from those in 1 and 2 due to the rotation of C–C single bond in bpe. Polymer 5 exhibits an interesting 3D porous framework with 2-fold interpenetration, in which intriguing 1D double helix chains are observed. The photoluminescence properties of 1 and 2 in the solid-state at room temperature are investigated. In addition, variable-temperature magnetic data show weak antiferromagnetic behavior in 3–5. [Copyright &y& Elsevier]

To systematically explore the influence of aromatic polycarboxylate ligands on building ZnII–BMP (1,5-bis(2-methylbenzimidazol) pentane) coordination polymers, four coordination polymers, namely {[Zn2(BMP)(PHSA)2]·H2O} n (1), [Zn4(BMP)2(BTEC)2(H2O)] n (2), [Zn2(BMP)(BTRC)(OH)] n (3), {[Zn3(BMP)(TCI)2(H2O)]·H2O} n (4) (H2PHSA=2-phenylsuccinic acid, H4BTEC=benzene-1,2,4,5-tetracarboxylic acid, H3BTRC=benzene-1,3,5-tricarboxylic acid, H3TCI=Tris (2-carboxyethyl) isocyanurate) are synthesized by varying aromatic polycarboxylate ligands. Systematic structure analysis shows that 1–4 are comprised by one or more ZnII dimer in which carboxylate ligands bridge two metal ions forming dinuclear cores, and BMP links these cores. In 1, PHSA2− bridges ZnII ions to generate paddle-wheel dimer [Zn2(η 1-COO)4] and these dimers are further linked by BMP to form 2D structure. 2 exhibits a layer with two different dimers: [Zn2(η 1-BTEC4−)2] and [Zn2(η 1-BTEC4−)(μ 2-H2O)] indicating that bridge water have subtle influences on the coordination geometry. [Zn2(η 1-BTRC3−)(μ 2-OH)] dimers in 3 are further linked by two kind of wavelike layers constructing the 2-fold interpenetrated 3D architecture. 4 shows a 2-fold interpenetrated 3D architecture with dimeric centre. Notably, besides ZnII dimer [Zn2(η 1-TCI3−)3], a monuclear ZnII ion exists as a terminal of ligand BMP enhancing photoluminescence intensity of 4 subtlely. [ABSTRACT FROM AUTHOR]

Abstract: Five new 0D–2D Cd(II) complexes, [Cd2(Hbimt)2I4] (1), [Cd(bimt)(Hbimt)Br] n (2), [Cd(Hbimt)Cl2(H2O)] n (3), {[Cd(Hbimt)(SO4)(H2O)2]·1.5H2O} n (4) and [Cd(Hbimt)(SCN)2] n (5) (Hbimt=2-((benzoimidazol-yl)methyl)-1H-tetrazole) have been synthesized by the reactions of Hbimt with suitable cadmium salts. Employment of different anions can influence the coordination modes of the Hbimt ligand, and accordingly result in different structures ranging from 0D to infinite 1D and 2D networks. Complex 1 displays a dimeric structure in which two Cd(II) ions are bridged through two iodine atoms. Complex 2 was caused by deprotonation of the Hbimt ligand, resulting in a 1D helical chain. While in complexes 3 and 4, Hbimt acts as a bidentate bridging ligand which joins two Cd(II) ions, leading to 1D stair-like chains. Complex 5 exhibits a 2D network structure with infinite 1D [Cd2(SCN)2] n chains. The distinct structures of 1, 2, 3, 4 and 5 reveal that the anions and the versatile coordination modes of the ligand play an important role in the structures of the complexes. In addition, the luminescent properties of complexes 1–5 have been investigated in the solid state at room temperature. [Copyright &y& Elsevier]

In the title compound, [Ni(C4H3N2O2)2(H2O)4] or [Ni(HDHPM)2(H2O)4] (H2DHPM = 4,6-dihydroxy­pyrimidine), the NiII atom, on an inversion centre, is six-coordinated by two N atoms from two HDMPM− ligands and four O atoms from four water mol­ecules. A three-dimensional supra­molecular structure is formed through π–π and hydrogen-bonding inter­actions. [ABSTRACT FROM AUTHOR]

In the title compound, [Ag2(C10H6NO2)2(C2H8N2)]·4H2O, each AgI atom is three-coordinated by one N atom and one O atom from one quinoline-2-carboxyl­ate anion, and by one N atom from one ethyl­enediamine ligand. The dinuclear mol­ecule is centrosymmetric. A three-dimensional supra­molecular structure is formed through hydrogen-bonding and π–π inter­actions. [ABSTRACT FROM AUTHOR]