Thermodynamic assessment of the ternary systems Ga-Mg-O, Ga-Ni-O, Mg-Ni-O and extrapolation to the Ga-Mg-Ni-O phase diagram

The available literature information on the thermodynamic properties and phase equilibria for the ternary systems Ga-Mg-O, Ga-Ni-O, and Mg-Ni-O has been critically assessed. New experimental data have been obtained for the Ga-Mg-O system. Based on the known thermodynamics of the boundary systems Ga-O, Mg-O, and Ni-O models have been defined to describe the Gibbs energy of the individual phases. The model parameters have been optimized by least-squares fit to the selected experimental information of different kind (phase diagram data, calorimetric data, and equilibrium oxygen pressures). A self-consistent set of Gibbs energy functions describing the oxide part of the Ga-Mg-Ni-O system, which contains two solution phases of halite- and spinel-type has been obtained for the first time.