Phase equilibria modeling in Bi2O3–SrO–MnO system

Abstract The selected pseudobinary, isothermal and isoactivity sections of the Bi 2 O 3 –SrO–MnO x phase diagram are constructed from the calculated phase equilibria. The starting point for the thermodynamic analysis were the assessments of the respective pseudobinary systems Bi 2 O 3 –SrO, Bi 2 O 3 –MnO x and SrO–MnO x . The only quaternary solid phase–the perovskite solid solution–is described in terms of the point defect model [ Bi 3+ 1− x Sr 2+ x ] [ Mn 3+ 1− x +2δ Mn 4+ x −2δ ] [O 2− 1−δ/3 V a δ/3 ] 3 . The quaternary liquid is approximated by a phenomenological model using the liquid species Mn, MnO, MnO 1.5 , SrO, and BiO 1.5 with only binary Redlich–Kister coefficients. The ab initio electronic structure calculations of cohesive energies are employed to evaluate the enthalpies of formation of some stoichiometric phases.