The stability constants of ternary M(II) complexes, [MLL′], where M refers to Cu(II) or Ni(II), L refers to ethylenediamine (en), 1,3-diaminopropane (1,3-pn), N,N-dimethylethylenediamine (N,N-dimen), N,N-diethylethylenediamine (N,N-dien) and L′ refers to catechol, catechuic acid, tiron, pyrogallol,o-aminophenol,o-phenylenediamine, oxalic acid, malonic acid, glycine, α-alanine, β-alanine, have been determined potentiometrically using the SCOGS computer program. LogKreprop. (reprop.-reproportionation) of ternary complexes have been calculated. The effecf of the nature of the ligand onKreprop. values has been discussed for these ternary complexes and the fact thatKreprop. is not a proper measure of the stability of the ternary complex has been indicated.
