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  • Author or Editor: I. Labádi x
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Various copper(II) complexes as guests were immobilised among the layers of montmorillonite or on silica gel as hosts. Anchoring took place through hydrogen bonds and ion exchange for montmorillonite, while the forces of interaction were either hydrogen bonding or covalent bonds for the copper complex-silica gel nanohybrids. The thermal stabilities of these substances were studied under oxidizing atmosphere and it was found that anchoring increased the durability of the host-guest complexes relative to the host-free ones.

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Abstract  

1,3-propanediaminotetramethylenephosphonic acid (PDTMP, H8L) was prepared and its complexes with some lanthanide ions (La(III), Eu(III), Gd(III) and Sm(III)) were isolated. The IR spectra and thermal stabilities of PDTMP and its complexes were studied. All the complexes contain physically and coordinately bound water molecules, which are released from the solid samples below 370C. On heating PDTMP decomposes to phosphorus oxides, while its anhydrous complexes decompose to lanthanide oxides, and cyclic and linear polyphosphates between 400 and 1000C.

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Abstract  

Mixed ligand complexes of different compositions were prepared with water, sulfate ion and 1,2-ethanediol as ligand. IR spectra and the thermoanalytical curves of the complexes were recorded. Oxygen atoms bound by one or two coordinate bonds to the metal ion, or by hydrogen-bonds in the crystal, were observed. As for the water molecule, 1,2-ethanediol molecules of crystal and monohydrate type were found, depending on the type of binding of the oxygen atoms.

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Summary  

Mixed ligand nickel(II) complexes of different compositions were prepared with water, sulfate ion and 1,2-ethanediol as ligands. The magnetic susceptibility data, the IR spectra and the thermoanalytical curves of the complexes were recorded. Oxygen atoms bound by one or two coordinate bonds to the metal ion, or by hydrogen-bonds in the crystal state were observed. All complexes are sensitive for moisture. The bis complex proved to be the more stable complex.

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Abstract  

Parent and mixed ligand complexes of manganese(II) ion were prepared with water, sulfate ion and 1,2-ethanediol as ligands. The IR spectra and the thermoanalytical curves of the complexes were recorded. Oxygen atoms bound by one or two coordinate bonds to the metal ion, or by hydrogen-bonds in the crystal, were observed. As for the water molecule, ‘crystal’ and ‘monohydrate’ type of 1,2-ethanediol molecules were found, depending on the type of binding of the oxygen atoms.

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Abstract  

Parent and mixed ligand complexes of cobalt and copper with antipyrine derivatives of 1,2-ethanediamine or piperazine and with 2-aminobenzothiazole (TAB) were synthesized and their thermal behaviour was investigated. The complexes contain N,N′-bis(4-antipyrylmethyl)-piperazine (BAMP) or N,N′-tetra(4-antipyrylmethyl)-1,2-diaminoethane (TAMEN) or/and TAB as ligand, and Cl, ClO4 or SCN. The complexes decompose with the evolution of heat. The decomposition route depends on the presence of ClO4 . If the ClO4 is not coordinated, it oxidizes the TAB and BAMP or TAMEN and the decomposition is explosive.

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Abstract  

Ethylenediaminotetramethylenephosphonic acid (EDTMP, H8L) was prepared and its complexes with some lanthanide ions (La, Eu, Gd and Sm) were isolated under various conditions. IR spectra and thermal stabilities of EDTMP and its complexes were studied. The experimental conditions of the preparation influence to the composition of the complexes were shown. In alkaline solution (pH=8) deprotonated (P(O)(O)2), and in acidic solution (pH=3–4) deprotonated and partly protonated (P(O)(O)(OH)) and non-protonated (P(O)(OH)2) phosphonic groups are present in the complexes. All the complexes contain coordinated water molecules. The complexes containing a protonated phosphonic group contain coordinated and hydrogen-bonded water molecules.

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Abstract  

Parent and mixed ligand complexes of cobalt(II) and copper(II) ions with N,N'-bis- (4-antipyrylmethyl)piperazine or N,N'-tetra(4-antipyryl-methyl)-1,2-diaminoethane or/and imidazole as ligand and ClO4 - or SCN- as counterion were synthesised and their thermal behaviour was investigated.

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Abstract  

Parent and mixed-ligand cobalt(II) complexes of different compositions were prepared with water, sulfate ion and 1,2-ethanediol as ligands. The magnetic susceptibility data, the IR spectra and the thermoanalytical curves of the complexes were recorded. Oxygen atoms bound by one or two coordinate bonds to the metal ion, or by hydrogen-bonds were observed in the crystals pace.

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