Preparation of some lanthanide violurate complexes

Violurate complexes of Ce3+, Pr3+, Pr4+, Nd3+, Sm3+, Eu3+, Gd3+, Dy3+, Ho3+, Er3+, and Yb3+ were prepared. The prepared complexes are freely soluble in hot water and dilute mineral acids. Thermal analysis (DTA, DTG, and TGA) show that the solid complexes are characterized by endo‐ and exothermic bands, indicating that they are degradated at different temperature stages. The IR spectra of the ligand and its metal complexes reveal that bonding takes place through coordination bonds between the central metal ion and the oxygen atom of the oximino (C = NO) group and the oxygen of the phenolic (ketonic group . All the isomorphous complexes, detected by the X‐ray diffraction patterns, have similar IR spectra.