Metal complexes involving the heavier donor atoms. Part I. Stabilities of metallic complexes of semicarbazide diacetic acid and thiosemicarbazide diacetic acid

Abstract

The ionisation constants of semicarbazide 1,1-diacetic acid and thiosemicarbazide 1,1-diacetic acid and the stability constants of their complexes with a number of dipositive alkaline earth and transition-metal ions have been determined by the potentiometric method and, in the case of the cupric ion, by the spectrophotometric method. The results provide information of the relative stability of complexes involving the donor atoms oxygen and sulphur when these are part of a carbonyl type linkage and are discussed in relation to earlier work using ligands in which the same donor atoms are part of an ether-type linkage.