Heat Capacity of the Gd2Ti2O7 and Lu2Ti2O7 Pyrochlores in the Range 350–1000 K.

The Gd2Ti2O7 and Lu2Ti2O7 titanates (pyrochlore structure, sp. gr. Fd3m) have been prepared by solid-state reactions in air at temperatures from 1673 to 1773 K using the Gd2O3, Lu2O3, and TiO2 oxides as starting materials. Their high-temperature heat capacity has been determined by differential scanning calorimetry in the range 350–1000 K. The experimental heat capacity data have been used to evaluate the thermodynamic functions of gadolinium and lutetium dititanates. [ABSTRACT FROM AUTHOR]