Low-temperature heat capacity and thermodynamic properties of crystalline [RE(Gly)(3)(H2O)(2)]Cl-3 center dot 2H(2)O (RE = Pr, Nd, Gly = Glycine)

Heat capacities of two solid complexes of rare-earth elements with glycine [RE(Gly)(3)(H2O)(2)]Cl-3.2H(2)O (RE = Pr, Nd, Gly = Glycine) have been measured with a high-precision automatic adiabatic calorimeter over the temperature range from 78 to 380 K. The melting point, molar enthalpy and entropy of fusion for the two complexes were determined on the basis of the heat capacity measurements. Thermal decompositions of the two complexes were studied by thermogravimetric (TG) techniques and a possible mechanism for the decompositions is suggested. (C) 2002 Elsevier Science B.V. All rights reserved