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Four new lanthanum(III) complexes of formulae [La(sac) 3 (phen) 2 (H 2 O) 2 ]·(phen)(H 2 O) 2 ( 1 ), [La(sac) 3 (phen) 2 (H 2 O) 2 ]·(phen) ( 2 ), [La(sac) 2 (phen)(H 2 O) 4 ]·(sac) ( 3 ) and [La(sac) 2 (phen) 2 (H 2 O) 3 ]·(sac)(phen)(H 2 O) ( 4 ) (phen = 1,10 phenanthroline, sac = saccharinate) have been synthesised and characterised by single crystal X-ray diffraction, IR, elemental analysis and thermogravimetric analysis. The binding mode of the sac anion was manipulated through the use of phen as structure inducer. In all four complexes the La(III) ion is in a nine-coordinate environment. The structures of 1 and 2 are similar, comprising of three sac anions coordinating in a monodentate fashion through the carbonyl O-atom, two bidentate phen and two water molecules coordinating directly to the same La(III) ion; a third, uncoordinated phen moiety also forms part of the unit cell. In addition, 1 is characterized by the presence of two crystallization water molecules which are absent in 2 . In compound 3 the coordination sphere of La(III) is completed by a bidentate chelating sac through the N- and carbonyl O-atoms, a monodentate sac, a bidentate phen and four water ligands; a third, uncoordinated sac is also present in the crystal lattice. Compound 4 contains two bidentate phen, three water ligands and two monodentate O(carbonyl) sac ligands. The presence of three sac anions coordinating to the same lanthanide ion as well as a bidentate N–Ln–O chelating sac, confirmed by single crystal X-ray crystallography, is unprecedented for rare-earth saccharinates. [ABSTRACT FROM AUTHOR]

The experimental and theoretical investigation results of a novel organic squarate salt of 4-Morpholinium bis(hydrogen squarate) ( 1 ), C 6 H 14 ON + · C 8 H 3 O 8 - , were reported in this study. The crystal structure of the title compound was found to crystallize in the triclinic P − 1 space group. In the crystals of 1 the morpholine ring adopts the chair conformation with the ethyl group in the equatorial and hydrogen atoms in axial positions. The hydrogen squarate anions are linked into a homoconjugated anion, [(HSQ) 2 H], by a short symmetric, nonlinear O8⋯H2⋯O2 hydrogen bond of 2.444 (2) Å. The structural and vibrational properties of the compound were also studied by computational methods of ab-initio performed on the compound at DFT/B3LYP/6-31++G(d,p) ( 2 ) and HF/6-31++G(d,p) ( 3 ) level of theory. The obtained calculation results on the basis of two models for both the optimized molecular structure and vibrational properties for the 1 obtained are presented and compared with the X-ray analysis result. On the other hand the molecular electrostatic potential (MEP), electronic absorption spectra, frontier molecular orbitals (FMOs), conformational flexibility and non-linear optical properties (NLO) of the title compound were also studied at the 2 level and the results are reported. In order to evaluate the suitability for NLO applications thermal analysis (TG, DTA and DTG) data of 1 were also obtained. [ABSTRACT FROM AUTHOR]

Abstract: The azo-ester compounds containing an acryloyloxy group were derived from phenol and 2,6-dimethylphenol; first azobenzene derivatives were prepared by reacting substituted benzenediazonium salts with phenol and 2,6-dimethylphenol then their acryloyloxy derivatives were synthesized in a Schotten–Bauman-type reaction. The characterisation of the synthesized azo-ester dye has been described by IR, UV–vis, 1H NMR, 13C NMR spectroscopic techniques, and elemental analysis. The influence of the substituents and acryloyloxy group on the spectral data of the synthesized compounds has been described. The thermal behaviour of the present compounds has been determined by means of differential thermal analysis (DTA) and thermogravimetry (TG) techniques. [Copyright &y& Elsevier]

A novel one-dimensional (1D) coordination polymer, {[Cu(hmpH) 2 Cu(hmp)(hmpH)Co(μ-CN) 4 (CN) 2 ]·2H 2 O} n ( 1 ) (hmpH = 2-pyridinemethanol), was synthesized and characterized by elemental analysis, spectral (FT-IR, Raman and EPR) methods, thermal analysis, single crystal X-ray diffraction and magnetic measurement techniques. In 1 , the Co(III) ions are six coordinated with six cyanide-carbon atoms in a octahedral arrangement. The Cu1 and Cu2 ions are coordinated with two cyanide-nitrogen atom, two nitrogen and two oxygen atoms from chelating two hmpH and hmpH/hmp ligands, respectively. The hmpH ligand in the complex has behaved as both anionic ligand (with its hydroxyl group being deprotonated) and as neutral form with the preserved OH group. The hydrogen bonding interactions between the crystal water molecules and hydroxyl group of hmpH ligands extends structure to the two dimensional (2D) supramolecular structure. The 2D layers were extended into 3D supramolecular networks by π⋯π and C–H⋯π interactions between pyridine rings of hmpH ligands. Variable temperature magnetic susceptibility measurement recorded in the 10–300 K range showed the presence of a very small antiferromagnetic within chains through CN bridges. Thermal stability and decomposition reactions of the complex take place in the temperature range 30–950 °C in a dry air atmosphere. [ABSTRACT FROM AUTHOR]

Three new coordination compounds, {[Cu(μ3-tdp)(phen)]·2H2O} n (1), {[Cu(μ3-tdp)(bipy)]·H2O} n (2), [Cu2(μ2-tdp)(phen)4](NO3)2·2H2O (3) [tdpH2 =3,3′-thiodipropionic acid, phen=1,10-phenanthroline, bipy=2,2′-bipyridine] were synthesized and characterized by the IR spectroscopy, elemental analysis, magnetic measurements and single crystal X-ray diffraction. Thermal behaviors and thermochromic properties of the complexes were investigated in detail. Complexes 1 and 2 are 1D coordination polymers while complex 3 is dinuclear structure. In complexes 1 and 2, the tdp acts as a tridentate bridging ligand to coordinate the two different Cu(II) centers to form 1D chain, which are extended into a 3D networks by hydrogen bonding and π⋯π interactions. The 3,3′-thiodipropionate ligand adopts a new coordination mode in 3. Furthermore, complex 3 changed the color from blue to green at 140°C at solid state. [ABSTRACT FROM AUTHOR]

Abstract: Three new cyano-bridged heteronuclear polymeric complexes, [Zn(NH3)2(μ–ampy)Ni(μ–CN)2(CN)2] n (1), [Zn(NH3)2(μ–ampy)Pd(μ–CN)2(CN)2] n (2) and [Zn(NH3)2(μ–ampy)Pt(μ–CN)2(CN)2] n (3) (ampy=4-aminomethylpyridine) have been synthesized and characterized by vibrational spectroscopy (FT-IR and Raman), thermal (TG, DTG and DTA) and elemental analyses. The crystal structures of complexes 1 and 2 have been determined by the X-ray single crystal diffraction technique. Complexes 1 and 2 crystallize in the triclinic system with the space group . Structural studies reveal that the Ni(II) or Pd(II) ions are four coordinate with four cyanide–carbon atoms in a square planar geometry and the Zn(II) ion exhibits a distorted octahedral coordination geometry completed by the six N atoms from two ammine, one ampy and two cyano ligands. The adjacent metal centers are bridged by bis-monodentate cyano ligands to form a one-dimensional linear chain. These chains are linked by ampy ligands into a 2D sheet structure. The 2D units are connected together via intramolecular C–H⋯N and intermolecular N–H⋯N hydrogen bonding to form 3D supramolecular networks. In additional, there are also interactions between the Ni(II) or Pd(II) ion and the aromatic π-system. Vibrational spectral data indicate the presence of two ν(C N) bands for the complexes, which can be assigned to the terminal and bridging cyanide ligands. Decomposition reactions take place in the temperature range 40–900°C in a static air atmosphere. [Copyright &y& Elsevier]

Abstract: A novel three dimensional Ag(I)-3,3′-thiodipropionate metal–organic framework, [Ag2(μ8-tdp)] n (1) (tdpH2 =3,3′-thiodipropionic acid), was synthesized and structurally characterized by FT-IR and photoluminescence spectroscopy, single crystal X-ray diffraction techniques and thermal analysis (TG, DTG and DTA). The compound crystallized in the monoclinic crystal system with the space group C2/c. The X-ray crystallographic study of 1 shows a short Ag⋯Ag contact with a distance of 3.022Å. The most striking feature of 1 is that it exhibits a 3D porous framework with 1D infinite channels, and complex 1 exhibits strong fluorescent emission bands in the solid state at room temperature. Moreover, atomically detailed simulations were used to assess the potential of the complex for H2 storage applications. [Copyright &y& Elsevier]