The heat capacity and derived thermodynamic functions of La2Zr2O7 and Ce2Zr2O7 from 4 to 1000 K

The heat capacities of cerium and lanthanum zirconate (Ce2Zr2O7 and La2Zr2O7) were measured from 4 to 400 K by adiabatic calorimetry. The derived thermodynamic functions, H degrees, S degrees and {G degrees - H degrees(0)}/T were calculated. The standard molar entropies at 298.15K were determined as 230.21 +/- 0.46 J/mol . K and 238.53 +/- 0.48 J/mol . K. Enthalpy increments relative to 298.15 K were measured by drop calorimetry from 500 to 900 K. From these data the thermodynamic functions; including the enthalpy and Gibbs free energy of formation of the two compounds were derived for temperatures up to 1000 K. Copyright (C) 1997 Elsevier Science Ltd.