Thermochemical assessment of the binary system Ba-O

Critically selected experimental data from the literature and estimated values are employed for the assessment of the Gibbs energies of all phases in the system Ba-O. The standard element reference state, SER, has been used throughout. For the gas phase the species BaG, BaG2, BaOG, Ba2OG2, Ba2OG, OG, OG2 and OG3 are employed. The liquid phase is modelled as an associated solution with the species BaL, BaOL and OL. Barium is treated as a pure stoichiometric substance. The excess solubility of oxygen in BaOs and the oxygen deficiency of BaOs2 are treated by a common solution phase between BaOs and BaOs2 with a miscibility gap.