Molecular dynamics simulation of binary CaO–FeO, MgO–SiO2, FeO–SiO2, CaO–SiO2 and ternary CaO–FeO–SiO2 systems

Molecular dynamics models of binary CaO–FeO, MgO–SiO2, FeO–SiO2, CaO–SiO2 and ternary CaO–FeO–SiO2 systems were constructed at 1873 K using the Born–Mayer pair potentials. The potentials included the effective dipole–dipole interactions for Ca–Fe, Mg–Si, Fe–Si and Ca–Si pairs. Parameters of the dipole–dipole interactions were found by adjusting calculated Gibbs free energies of formation of binary CaO–FeO, FeO–SiO2, MgO–SiO2 and CaO–SiO2 systems to experimental data. The thermodynamic properties of CaO–FeO–SiO2 solutions were studied by converting several iron ions into calcium ions. The Gibbs free energy increments and ratios of activity coefficients γCaO/γFeO in the ternary system were calculated.