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Four new mercury coordination polymers were successfully synthesized under solvothermal conditions and characterized by elemental analysis, IR spectroscopy, thermal analysis, powder X-ray diffraction and single-crystal X-ray diffraction. In these complexes, the chemical valence of mercury is +2, except for complex 1 which is +1. 1 contains [Hg2]2+ metal–metal bonded cores which are bounded by atz− (Hatz = 5-amino-tetrazolate) ligands and features a two-dimensional (2D) uninodal 3-connected ‘hcb’ network. 2 exhibits a trinodal 3D (3,6)-connected ‘apo/alpha-PbO2’ topological net in which 2D [HgCl]nn+ inorganic cation layers are pillared by atz− ligands. In 3, the 2D [HgCl]nn+ cation layers are interconnected by atz− ligands, affording a trinodal 3D (3,6)-connected ‘flu/fluorite’ topological net. 4 is a 3D pillared-layer metal–organic framework based on mixed atz− and isonicotinic ligands, showing a binodal (4,6)-connected ‘fsc’ coordination network. In this work, 1 and 4 were synthesized from an in situ generated tetrazolate ligand, while 2 and 3 were prepared from a commercially available tetrazolate ligand. These results indicate that the final structures of the target complexes will highly depend on the synthetic conditions as well as the preparation methods. Moreover, the photoluminescence properties of these complexes were investigated. Impressively, the non-centrosymmetric complex 3 displays not only a second harmonic generation (SHG) response but also a ferroelectric behavior. [ABSTRACT FROM AUTHOR]

A new type of ionic ferroelectric based on a chiral salen-type Schiff base erbium(III) complex ( ErL) was synthesized by the reaction of erbium nitrate with the ligand N, N′-bis(3,5-dichlorosalicylidene)-(1 S,2 S)-1,2-cyclohexylenediamine ( L). The structures of the ligand L and the complex ErL were determined by single-crystal X-ray diffraction. The results indicated that ErIII not only acts as central metal atom to coordinate with two Schiff base ligands, but also as Lewis acid catalyst to promote the partial decomposition of another salen-type Schiff base ligand. The central ErIII atom adopts an octacoordinate square antiprismatic arrangement with Λ absolute configuration, coordinating with all nitrogen and oxygen atoms of two ligands due to the influence of the strong electron-withdrawing group on the Schiff base ligand. The complex ErL exhibits good SHG and ferroelectric properties. The results provide a simple and effective approach to construct rare earth complexes coordinated with nitrogen and oxygen atoms of salen-type Schiff base ligands with technologically important properties such as SHG activity and ferroelectricity. [ABSTRACT FROM AUTHOR]

A new type of multifunctional single ionic chiral dysprosium complex ( DyL ) was obtained by the reaction of Dy(NO 3 ) 3 and salen-type Schiff base ligand N,N′-bis(3,5-dichlorosalicylidene)-(1 R ,2 R )-1,2-cyclohexylenediamine. In the synthesis reaction, Dy(III) was found not only to be the central metal to coordinate with two Schiff base ligands, but also the Lewis acid catalyst to promote the partial decomposition of salen-type Schiff base ligand. Complex DyL crystallizes in a chiral and polar space group P 2 1 . The central metal Dy(III) adopts eight-coordinated square antiprism geometry with Δ absolute configuration. Complex DyL exhibits good SHG and ferroelectric properties. The single-crystal sample of DyL displays an obvious ferroelectric behavior with a remnant polarization ( P r ) of ca. 4.51 μC cm −2 and E c of ca. 28.11 kV cm −1 . The solid luminescent spectrum of DyL presents characteristic emission 4 F 9/2 → 6 H 15/2 and 4 F 9/2 → 6 H 13/2 transitions of Dy(III). [ABSTRACT FROM AUTHOR]

Abstract: One couple of enantiomerically pure chiral CuIIGdIII coordination polymers [Cu((S, S)-Salcy)Gd(NO3)3·CH3OH] n (1) and [Cu((R, R)-Salcy)Gd(NO3)3·CH3OH] n (2) [(S, S)-Salcy or (R, R)-Salcy=(S, S)- or (R, R)-N, N′-(1,2-cyclohexanediylethylene) bis(3-ethoxysalicylideneiminato)dianion], were synthesized and structurally characterized. The self-assembly by intermolecular semicoordination of nitrate to copper(II) formed a one-dimensional zigzag chain structure. Magnetic property studies indicated that 1 and 2 exhibited very strong ferromagnetic interaction (J =6.285 and 7.408cm−1, respectively) between copper(II) and gadolinium(III) metal centers among the related complexes, although the dihedral angles (8.1° and 8.6°, respectively) of CuO2 and GdO2 are a little large. [Copyright &y& Elsevier]

Abstract: A new Mn(II) complex, [Mn2(edta)(H2O)] n ·nH2O (1) (H4edta=ethylenediaminetetraacetic acid) has been synthesized by the reaction of MnCl2·4H2O and H4edta under hydrothermal conditions, and was characterized by single-crystal X-ray diffraction study, variable temperature (1.8–300K) magnetic measurement, and thermal gravity analysis. The result of X-ray crystallographic analysis reveals that complex 1 is the first two-dimensional (2D) Mn-edta coordination polymer with a grid-like (4,4)-topology, which is built from Mn-carboxylate chains and entirely deprotonated edta4− ligands with a maximum denticity. The variable temperature magnetic data indicate that complex 1 exhibits strong antiferromagnetic couplings. [Copyright &y& Elsevier]

Abstract: A new coordination polymer, [Cd4(atz)6(PTA)] n has been firstly synthesized by employing mixed-ligand of terephthalic acid (PTA) with the in-situ generated ligand of 5-amino-tetrazolate (atz−). Compound 1 represents a 3D microporous framework constructed from Cd-tetrazolate subunits and the subunits are bridged by PTA and atz ligands. When the subunit was collided into node, compound 1 possesses an unprecedented 3, 9-connected topological network. Furthermore, the investigations of thermal stability and luminescent property of complex 1 indicate that compound 1 may be an excellent candidate for potential blue-light emitting material. [Copyright &y& Elsevier]

Three N,N-bidentate ligands, 5,5′-dibromo-2,2′-bipyridine (L1) and two carbazole containing ligands of 5-bromo-5′-carbazolyl-2,2′-bipyridine (L2), 5,5′-dicarbazolyl-2,2′-bipyridine (L3), and their corresponding rhenium Re(CO)3Cl(L) complexes (ReL1–ReL3) have been successfully synthesized and characterized by elemental analysis, 1H NMR and IR spectra. Their photophysical properties and thermal analysis, along with the X-ray crystal structure analysis of L3and complexes ReL1and ReL3are also described. In CH2Cl2solution at room temperature, all complexes display intense absorption bands at ca.220–350 nm, which can be assigned to spin-allowed intraligand (π→π*) transitions, and the low energy broad bands in the 360–480 nm region are attributed to the metal to ligand charge-transfer dπ(Re)→π* (diimine) (MLCT). The introduction of carbazole moieties improves the MLCT absorption and molar extinction coefficient of these complexes. Upon excitation at the peak maxima, all complexes show strong emissions around 620 nm, which are assigned to dπ(Re)→π* (diimine) MLCT phosphorescence. The photoluminescence lifetime decay of Re(I) complexes were measured and the quantum efficiencies of the rhenium(I) complexes were calculated by using air-equilibrated [Ru(bpy)3]2+·2Cl−aqueous solution as standard (Φstd= 0.028). The complexes with appended carbazole moieties exhibit enhanced luminescence performances relative to ReL1. [ABSTRACT FROM AUTHOR]

Abstract: Two sets of 3d–4f complexes [(NiL)nRE] (n=1, 2; RE=La and Ce; H2L=N,N′-bis(3-ethoxysalicylidene)ethylenediamine) were obtained by reacting NiL with RE(NO3)3 in the ratios of 1/1 and 2/1, respectively. With the NiL/RE ratio changing from 1/1 to 2/1, not only the crystal structures were changed from discrete dinuclear complexes [(NiL)RE] to sandwich-like trinuclear complexes [(NiL)2RE], but also the biological activities were greatly influenced. The trinuclear complexes [(NiL)2RE] exhibited higher antimicrobial activities than the corresponding dinuclear counterpart [(NiL)RE]. [Copyright &y& Elsevier]

A heteronuclear CuII–SmIII complex (systematic name: {6,6′-diethoxy-2,2′-[ethane-1,2-diylbis(nitrilomethylidyne)]diphenolato-1κ4 O1, O1′, O6, O6′:2κ4 O1, N, N′, O1′}trinitrato-1κ6 O, O′- samarium(III)copper(II)), [CuSm(C20H22N2O4)(NO3)3], with the hexadentate Schiff base compartmental ligand N, N′-bis(3-ethoxysalicylidene)ethylene-1,2-diamine, has been synthesized and structurally characterized. The Cu and Sm atoms are doubly bridged by two phenolate O atoms provided by the Schiff base ligand. The coordination of the Cu atom is square planar, formed by two imine N and two phenolate O atoms. The SmIII atom has a decacoordination environment, formed by the phenolate O atoms, two ethoxy O atoms and two O atoms each from the three nitrates. No classical intermolecular hydrogen bonds are found. Some weak C—H...O and O...Cu interactions [O...Cu = 3.167 (4) Å] generate a two-dimensional zigzag sheet. [ABSTRACT FROM AUTHOR]

The title compound, [Sn(C6H5)3(C19H16N3O3)], is a four-coordinate SnIV complex, with a distorted tetrahedral geometry and one disordered (0.54:0.46) phenyl ring. The Schiff base carboxylate group acts as a monodentate ligand coordinating through the deprotonated hydroxyl O atom. In the crystal structure, a weak offset face-to-face aromatic π–π stacking interaction can be found between the pyrazole ring and the benzene ring of 4-formylbenzoic acid. The centroid-to-centroid distance is 3.858 (2) Å and the interplanar distance is 3.375 (4) Å. [ABSTRACT FROM AUTHOR]

Highlights: [•] A new Cu coordination polymer with mixed-ligands has been synthesized. [•] The 3D framework was proved by single-crystal X-ray diffraction. [•] Title compound is an unprecedented 3,5-connected ‘ fet’ topological network. [ABSTRACT FROM AUTHOR]

Abstract: A new 3D coordination polymer, Mn2(atz)(isonic)(OH)(Cl)]n (1), was synthesized hydrothermally from mixed-ligands of Hatz (Hatz=5-amino-tetrazolate) and Hisonic (Hisonic=isonicotinate) and corresponding metal salts. It was characterized by IR spectra, elemental and thermal analysis, single crystal and powder X-ray diffraction. Variable temperature magnetic investigations indicate that compound 1 exhibits typical antiferromagnetic behaviors. [Copyright &y& Elsevier]