Thermodynamic treatment of noble metal fission products in nuclear fuel

Based on a critical evaluation of the literature, a comprehensive thermodynamic model has been developed for the complete quinary system involving the noble metal fission products in nuclear fuel: Mo–Pd–Rh–Ru–Tc. This treatment was based on the foundation of ten binary systems and an interpolation scheme. The thermodynamic model has been demonstrated to fit the available experimental data for the ternary sub-systems. This work can be used with other models for potentially non-stoichiometric UO2+x containing fission products, as well as data for other phases, to assess the chemical form of fission products in irradiated fuel material.