Metal complexes involving the heavier donor atoms. Part IV. Stability and heats of formation of cupric complexes of semicarbazide, thiosemicarbazide, and selenosemicarbazide

Abstract

The stability constants of copper(II) complexes of semicarbazide, thiosemicarbazide, and selenosemicarbazide have been measured by the spectrophotometric method and also in the case of semicarbazide by the pH method. The heats of formation were measured calorimetrically. From the stability constants the affinity order of the donor atoms is O S > Se but the enthalpy changes follow the order O S < Se.