Formation constants in the ternary systems: CuII-dipeptideamino acids

Summary A potentiometric titration technique has been used to determine formation constants for the various complexes of Cu^II with amino acids (L) and dipeptides (B) at 298 K and I-0.1 M (NaClO₄). The structure and mode of bonding in binary and ternary complexes are discussed. Values of log are evaluated. The plots of pK of amino acidsversus log K for the present and the earlier known systems gave an empirical relation: pK=–5.3 log K+10.5.