High-temperature heat capacity of stannates Pr$_{2}$Sn$_{2}$O$_{7}$ and Nd$_{2}$Sn$_{2}$O$_{7}$

Oxide compounds Pr$_{2}$Sn$_{2}$O$_{7}$ and Nd$_{2}$Sn$_{2}$O$_{7}$ have been obtained by solid-phase synthesis. The effect of temperature on the heat capacity of Pr$_{2}$Sn$_{2}$O$_{7}$ (360–1045 K) and Nd$_{2}$Sn$_{2}$O$_{7}$ (360–1030 K) has been studied using differential scanning calorimetry. The thermodynamic properties of the compounds (changes in enthalpy, entropy, and the reduced Gibbs energy) have been calculated by the experimental data of $C_p = f(T)$.