Thermochemistry of Hf-zirconolite, CaHfTi2O7

The formation enthalpy, -3,752.3 ± 4.7 kJ/mol, of Hf-zirconolite, CaHfTi2O7 was obtained using high temperature oxide-melt solution calorimetry. Combined with heat capacity data obtained using low temperature adiabatic calorimetry the authors report the heat capacity (Cp) and the standard molar formation energetics for Hf-zirconolite from T = 298.15 K to T = 1,500 K. Comparison of Hf-zirconolite with Zr-zirconolite is made