Thermodynamics of the Formation of Bis-Complexes of Copper(II) and Triglycine in Aqueous Solutions

摘要

Enthalpies of interaction between triglycine solutions and Cu(NO_3)_2 solutions are measured via direct calorimetry at a temperature of 298.15 K and in the 0.2_(–1).0 (KNO_3) range of ionic strength. The enthalpies of the formation of CuL_2, CuH_(–1)L_2~-, and CuH_(–2)L_2~(2-) complexes are calculated using results from calorimetric experiments. The thermodynamic characteristics (Δ_rH~°, Δ_rG~°, Δ_rS~°) of complex formation are determined. The structures of the studied complexes were proposed on the basis of their thermodynamic parameters and the results from spectrophotometric investigations.