role of some metal ions on the dissociation of disubstituted arylazo barbituric and thiobarbituric acids

Potentiometric studies of some disubstituted arylazo barbituric and thiobarbituric acids were carried out. The dissociation constants of the organic compounds and the stability constants of the metal complexes were calculated. The nodes of ionization of the free ligands were explained. The data were explained from different views: the ionization potential of the metal, the atomic radius of the metal and the electronic character of the substituent. A linear free energy relationship between pK[L]and log K[C]values were deduced and explained

Adduct formation constants of 1,2-nickel 2,4-dinitroso resorcinol complex with some nitrogen bases

Nickel [II] complex of 2,4-dinitrosoresorcinol is of four coordinate structure with 1:2 stoichiometry. The caaplea; forms adducts with some nitrogen bases where the coordination number is expanded. The adduct formation constants are calculated. The data are explained from the view the ligand basicity properties