Heat Capacity and Thermal Expansion of Lanthanum Hafnate

The molar heat capacity of lanthanum hafnate of the pyrochlore structure type was measured by differential scanning calorimetry in the temperature range 310–1380 K. The temperature dependence of the unit cell parameter a in the range 303–1273 K was characterized. The absence of structural transformations was demonstrated, and the thermal expansion coefficients in this temperature range were estimated.