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Czakis-Sulikowska D., Czylkowska A., Markiewicz M., Frajtak M.

Polish Journal of Chemistry

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2009

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Vol. 83, nr 11

1893-1901

EN

New mixed-ligand complexes of general formulae Ln(4-bpy)(CCl2HCOO)3źnH2O (4-bpy = 4,4'-bipyridine, Ln = lanthanide(III), n = 1 for Gd, n = 2 for Tb, Ho) and Tm(4-bpy)1.5(CCl2HCOO)3ź3H2O have been prepared and characterized by elemental and thermal analysis, IR spectroscopy and conductivity studies. The thermal properties of complexes were investigated in air atmosphere. During the heating the complexes decompose via intermediates to the oxides: Ln2O3 and Tb4O7. The principal volatile products of pyrolytic decomposition of Ho(III) and Tm(III) complexes, detected by a coupled TG-MS system are: C+, H2O+, CO2 + and species containing halogens and nitrogen. IR spectra suggest that 4-bpy and dichloroacetate groups are coordinated with Ln(III) ions.

2

Synthesis, Characterization and Thermal Decomposition of Yttrium and Light Lanthanides with 4,4'-Bipyridine and Dichloroacetates

Czakis-Sulikowska D., Czylkowska A., Markiewicz M.

Polish Journal of Chemistry

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2007

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Vol. 81, nr 7

1267-1275

EN

A novel mixed-ligand complexes with empirical formulae: Ln(4-bpy)(CCl2HCOO)3.H2O (where:Ln =Y, Ce,Nd, Pr andEu, 4-bpy = 4,4'-bipyridine) were prepared and characterized by chemical and elemental analysis, IR spectroscopy and conductivity measurements (in methanol, dimethylformamide and dimethylsulfoxide). Analysis of the powder diffraction patterns showed that the obtained complexes are crystalline and isostructural compounds. 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: Ln2O3 (Y, Nd, Eu), Pr6O11 and CeO2. A coupled TG-MS system was used to analyse principal volatile thermal decomposition (or fragmentation) products evolved during pyrolysis of Pr(III) and Nd(III) complexes. In air major profiles for ion currents are observed with m/z = 12, 18, 29, 30, 35, 36, 44, 47 amongst others.

3

Mixed-ligand Ni(II) and Zn(II) Complexes with Bipyridine Isomers and Bromoacetates

Czakis-Sulikowska D., Czylkowska A., Malinowska A.

Polish Journal of Chemistry

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2005

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Vol. 79 / nr 10

1635-1634

EN

New mixed-ligand complexes of the following stoichiometric formulae: Ni(2-bpy)2- (CBr2HCOO)2.5H2O, Ni(4-bpy)2(CBrH2COO)2.2H2O, Ni(4-bpy)2(CBr2HCOO)2 .2H2O, Ni(2,4'-bpy)2(CBr2HCOO)2 .4H2O, Zn(2-bpy)(CBrH2COO)2 .H2O and Zn(4-bpy)(CBr2HCOO)2.H2O (where: 2,2'-bipyridine = 2-bpy, 4,4'-bipyridine = 4-bpy and 2,4'-bipyridine = 2,4'-bpy) were isolated in pure state. The IR and VIS spectra, molar conductivity, magnetic moments are discussed. Thermal behaviours of complexes were studied by means of DTA, DTG, TG techniques under static air conditions. During heating the complexes decompose via different intermediate products. The final product of nickel(II) complexes pyrolysis was NiO; in the case of zinc(II) complexes total mass loss was observed.