Thermal behavior and other properties of Pr(III), Sm(III), Eu(III), Gd(III), Tb(III) complexes with 4,4′-bipyridine and trichloroacetates

Abstract

A novel mixed-ligand complexes with empirical formulae: Ln(4-bpy) 1.5 (CCl 3 COO) 3 ÁnH 2 O (where Ln(III) = Pr, Sm, Eu, Gd, Tb; n = 1 for Pr, Sm, Eu and n = 3 for Gd, Tb; 4-bpy = 4,4 0-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: Pr 6 O 11 , Ln 2 O 3 (for Sm, Eu, Gd) and Tb 4 O 7. 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.

Synthesis, structure and thermokinetic studies on perchlorate salts of metal complexes containing a formamidine-type ligand

“…The result of the peak extraction at 5°C min -1 is shown in figures 3 and 4. Isostructural compounds usually have very similar decomposition patterns [40,41]. However, with sensitive equipment even slight differences in the decomposition can be detected [42].…”

Lanthanide Complexes with 2,3-Dimethoxybenzoic Acid and Terpyridine: Crystal Structures, Thermal Properties, and Antibacterial Activities

“…The search of lanthanide aromatic carboxylic acid complexes have aroused great interest for their various and fascinating structures, which exhibit potential applications for extraction and separation, drug delivery, luminescent probes, and so on . These complexes combine central metallic units with organic N‐donor, which may enhance conjugate function, rigidity and stability, and reinforce the luminescent properties of the complexes . Furthermore, aromatic carboxylic acids exhibiting high affinity to central lanthanide atoms are chosen as conjugated organic ligands, since they have strong coordination capability to the lanthanide ions .…”

Crystal Structures, Thermal Properties, and Biological Activities of a Series of Lanthanide Compounds with 2,4-Dichlorobenzoic Acid and 1,10-Phenanthroline

“…In recent years, the design and synthesis of lanthanide aromatic carboxylic acid compounds have continued to be an active area of research of their various structures − and potential application in many areas such as extraction and separation, catalysts, luminescent probes, nonlinear optics (NLO), magnetism, and so on. − The introduction of nitrogen-containing ligands may strengthen conjugate function, enhance rigidity and stability, and reinforce fluorescence ability of the compounds. − As we know, certain lanthanide aromatic carboxylic acid compounds possess anti inflammation, sterilization, and antitumor activities, , which is significant as biological pharmaceutical. Therefore, a need is appearing to synthesize compounds that have better biological activity than that of the ligands.…”