摘要:
Mixed-ligand complexation of yttrium subgroup lanthanide ethylenediaminetetraacetates with asparaginate, iminodiacetate, and nitrilotriacetate ions in aqueous solution was studied by calorimetry and pH-metry. The full set of thermodynamic parameters (logK, Delta (r) G (0), Delta (r) H, Delta (r) S) of the addition reactions of Asp(2-), Ida(2-), and Nta(3-) to LnEdta(-) (Ln(3+) = Tb3+, Dy3+, Ho3+, Er3+, Tm3+, Yb3+, Lu3+) was determined at 298.15 K and ionic strength I = 0.5(KNO3). The change in the thermodynamic parameters of the reactions over the series of lanthanides was discussed.