POTENTIOMETRIC INVESTIGATION OF TERNARY COMPLEXES OF NICKEL, COPPER, ZINC AND CADMIUM WITH L-ALPHA-ALANINEHYDROXAMIC ACID AND ETHYLENEDIAMINE

Mixed-ligand complex formation of M(II) (M = Ni, Cu, Zn and Cd) with 1 -alpha-alaninehydroxamic acid (alpha-Alaha) as primary ligand (A) and ethylenediamine (en) as secondary ligand (B) have been determined pote ntiometrically [298 K, mu=0.2 (KCl)]. Formation constants for binary s ystems involving L-alpha-alaninehydroxamic acid or ethylenediamine wer e determined under identical experimental conditions and pH-titration data were analysed using the SUPERQUAD computer program. The relative stability of each ternary complex was compared with that of the corres ponding binary complexes in terms of Delta log K and log X values.