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New Y(III) and La(III) complexes with 4-bpy (4,4′-bipyridine) and trichloro- or dibromoacetates with the formulae: Y(4-bpy)(CClCOO)·HO I, La(4-bpy)(CClCOO)·2HO II, Y(4-bpy)(CHBrCOO)·3HO III, and La(4-bpy)(CHBrCOO)·HO IV were prepared and characterized by chemical, elemental analysis, and IR spectroscopy. Conductivity studies (in methanol, dimethyloformamide, and dimethylsulfoxide) were also described. They are small, crystalline substances. The way of metal-ligand coordination was discussed. The thermal properties of complexes in the solid state were studied by TG-DTG techniques under dynamic flowing air atmosphere. TG-FTIR system was used to analyze principal volatile thermal decomposition and fragmentation products evolved during pyrolysis in dynamic flowing argon atmosphere for La(III) compounds. [ABSTRACT FROM AUTHOR]

novel mixed-ligand complexes with empirical formulae: Ln(4-bpy)(CClCOO)· nHO (where Ln(III) = Pr, Sm, Eu, Gd, Tb; n = 1 for Pr, Sm, Eu and n = 3 for Gd, Tb; 4-bpy = 4,4′-bipyridine) were prepared and characterized by chemical, elemental analysis and IR spectroscopy. Conductivity studies (in methanol, dimethylformamide and dimethylsulfoxide) were also described. All complexes are crystalline. The way of metal-ligand coordination was discussed. The thermal properties of complexes in the solid state were studied under non-isothermal conditions in air atmosphere. During heating the complexes decompose via intermediate products to the oxides: PrO, LnO (for Sm, Eu, Gd) and TbO. TG-MS system was used to analyze principal volatile thermal decomposition and fragmentation products evolved during pyrolysis of Pr(III) and Sm(III) compounds in air. [ABSTRACT FROM AUTHOR]

New mixed ligand complexes of the following stoichiometric formulae: M(2-bpy)2(RCOO)2· nH2O, M(4-bpy)(RCOO)2·H2O and M(2,4’-bpy)2(RCOO)2·H2O (where M(II)=Zn, Cd; 2-bpy=2,2’-bipyridine, 4-bpy=4,4′-bipyridine, 2,4′-bpy=2,4′-bipyridine; R=C2H5; n=2 or 4) were prepared in pure solid-state. These complexes were characterized by chemical and elemental analysis, IR and conductivity studies. Thermal behaviour of compounds was studied by means of DTA, DTG, TG techniques under static conditions in air. The final products of pyrolysis of Cd(II) and Zn(II) compounds were metal oxides MO. A coupled TG/MS system was used to analyse of principal volatile products of thermal decomposition or fragmentation of Zn(4-bpy)(RCOO)2·H2O under dynamic air and argon atmosphere. The principal species correspond to: C+, CH+, CH3 +, C2H2 +, HCN+, C2H5 + or CHO+, CH2O+ or NO+, CO2 +, 13C16O2 + and 12C16O18O+ and others; additionally CO+ in argon atmosphere. [ABSTRACT FROM AUTHOR]

New mixed-ligand complexes with empirical formulae: Mn(2-bpy)1.5L2·2H2O, M(2-bpy)2L2·3H2O ( M(II)=Co, Cu), Ni(2-bpy)3L2·4H2O and M(2,4’-bpy)2L2·2H2O (where 2-bpy=2,2’-bipyridine, 2,4’-bpy=2,4’-bipyridine; L=HCOO– ) have been obtained in pure solid-state. The complexes were characterized by chemical and elemental analysis, IR and VIS spectroscopy, conductivity (in methanol and dimethylsulfoxide). The way of metal-ligand coordination discussed. The formate and 2,4’-bpy act as monodentate ligands and 2-bpy as chelate ligand. The new complexes with ligand isomerism were identified. During heating the complexes lose water molecules in one or two steps. Thermal decomposition after dehydration is multistage and yields corresponding metal oxides as final products. A coupled TG-MS system was used to analysis principal volatile thermal decomposition (or fragmentation) products of Ni(2,4’-bpy)2(HCOO)2·2H2O under dynamic air or argon atmosphere. [ABSTRACT FROM AUTHOR]

2,4′-Bipyridyl (2,4′-bipy or L) complexes with cobalt(II), nickel(II) and copper(II) of the formulae M(2,4′-bipy)2(CH3COO)2·2H2O (M(II) = Co, Ni, Cu), Co(2,4′-bipy)2SO4·3H2O or Ni(2,4′-bipy)2SO4·4H2O have been prepared and their IR and electronic (VIS) spectra are discussed. The thermal behaviour of the obtained compounds has also been studied. The intermediate products of decomposition at different temperatures have been characterized by chemical analysis and X-ray diffraction. [ABSTRACT FROM AUTHOR]