Thermochemical Study of Mixed Ligand Complexes of Rare Earths with Glycine and L-alanine

摘要

In order to obtain the standard molar enthalpies of formation of Rare-Earth amino acid coordination compounds, precise isothermal solution-reaction calorimetric method was used. The value of Δ-rHΘ-m of two coordination reactions was determined at T = 298.2 K. From the experimental results and other auxiliary values, the standard molar enthalpies of formation of Ln(Gly)- 5/2(Ala)- 3/2 (ClO-4)-3·H-2O(s) [Ln = La, Yb] at T = 298.2K were obtained. The values of them is to be Δ-rHΘ-m [La(Gly)- 5/2(Ala)- 3/2(ClO-4)-3·H-2O(s)] =-3545.45 kJ/ mol and Δ-rHΘ-m [Yb(Gly)- 5/2(Ala)- 3/2(ClO-4)-3·H-2O(s)]= -3793.81kJ/mol, respectively.