Zirconolite (CaZrTi2O7) has been proposed as a host phase for excess weapons plutonium, and the standard molar entropy ΔA298.15 K0 Som and other derived thermodynamic functions are needed to describe it completely. The heat capacity of CaZrTi2O7 has been measured from T ≈ 20 K to T ≈ 400 K with an adiabatic calorimeter. A six-term fitting equation based on Debye and Einstein functions has been shown to represent the heat capacity over the entire range of temperature to within the experimental uncertainty. This equation has been used to calculate the thermodynamic functions to T = 400 K and to extrapolate these functions to T = 1500 K. In particular, Δ298.15 K0 Som for CaZrTi2O7 is 193.3 J · K-1 · mol-1.
- Heat capacity
- Nuclear waste
- Plutonium disposition
ASJC Scopus subject areas
- Atomic and Molecular Physics, and Optics
- Materials Science(all)
- Physical and Theoretical Chemistry