Thermodynamic analysis of high-temperature heazlewoodite

Abstract

Abstract Experimental data for phase equilibria and thermodynamic properties have been used for thermodynamic analysis of the high-temperature heazlewoodite. A two-sublattice model in the framework of the Compound Energy Formalism is proposed for the Gibbs energy of a second high-temperature heazlewoodite phase around the composition Ni3S4. Optimized model parameters have been obtained which reproduce all data simultaneously within experimental error limits. The Gibbs energy modeling is carried out consistently with the recent assessment by the author of the nickel – sulfur system at 1 bar pressure over the entire composition range for temperatures from 25 °C to above the liquidus.