LAUSR

Enthalpy measurements have been taken on GdSmTi2O7 and DySmTi2O7 by using a high-temperature differential calorimeter at temperature between 800 and 1655 K. Thermodynamic function, such as heat capacity, entropy and Gibbs energy functions of GdSmTi2O7 and DySmTi2O7, was derived using the data obtained in this study. The results are presented and compared with the data available in the literature. The polynomial expression of enthalpy increments obtained for GdSmTi2O7(s) and DySmTi2O7(s) in the temperature range 298–1700 K is given as: $$\begin{aligned} H_{\text{T}}^{0} - H_{298}^{0} / {\text{J}}\,{\text{mol}}^{ - 1} & = 252.961\,T \, + 1.596 \times 10^{ - 2} \,T^{2} + 3.705 \times 10^{6} \,T^{ - 1} - 89{,}265\quad ({\text{GdSmTi}}_{2} {\text{O}}_{7} ) \\ H_{\text{T}}^{0} - H_{298}^{0} / {\text{J}}\,{\text{mol}}^{ - 1} & = 256.504\,T \, + 1.576 \times 10^{ - 2} \,T^{2} + 3.531 \times 10^{6} \,T^{ - 1} - 89{,}721\quad \left( {{\text{DySmTi}}_{2} {\text{O}}_{7} } \right). \\ \end{aligned}$$HT0-H2980/Jmol-1=252.961T+1.596×10-2T2+3.705×106T-1-89,265(GdSmTi2O7)HT0-H2980/Jmol-1=256.504T+1.576×10-2T2+3.531×106T-1-89,721DySmTi2O7.