Activity-composition relations of the magnesiowüstite solid solution series in equilibrium with metallic iron in the temperature range 1050–1400 K

Thermodynamic data for phases in the FeO-MgO-SiO2 system and phase relations in the mantle transition zone

“…The deviations from ideality in magnesiowustite obtained in this study are less than it was experimentally determined for nonstoichiometric magnesiowustite by Srecec et al (1987). There errors in the mixing parameters and enthalpy and entropy values are related and can not be independently evaluated.…”

Mineral formation in stellar winds

“…The magnesiowüstite can be conceived as a solid solution formed from the solids FeO, Fe 2 O 3 and MgO (Srečec et al 1987). The Fe 2 O 3 component accounts for the lattice vacancies in wüstite.…”

“…The activity coefficients of the solution components of magnesiowüstite have been determined for instance by Srečec et al (1987) at standard pressure p 0 and at temperatures between 1050 and 1400 K. By fitting quadratic asymmetric Margules (27) In applying this to the formation of magnesiowüstite in circumstellar shells we need to apply the activity coefficients γ considerably outside of the temperature regime for which they have been determined in the laboratory (cf. Fig.…”

Internal displacement reactions in multicomponent oxides: Part II. Oxide solid solutions of wide composition range

“…[14] are noted. The composition profile in the product oxide of Reaction [1] should show concentration gradients for all three cations: N A decreases toward the reaction front, N B increases toward the reaction front, and the inert cation N C increases toward the reaction front.…”

“…Several studies are available for the thermodynamic activities of MgO in (Ni,Mg)O, [10,11] (Fe,Mg)O, [12][13][14][15] and (Co,Mg)O [16][17][18][19] solid solutions. The system (Ni,Mg)O is nearly ideal, while (Fe,Mg)O exhibits a positive deviation from ideality in all the studies.…”