The Effects of FeO and Fe2O3 on the Structure and Properties of Aluminosilicate System: A Molecular Dynamics Study

FeO and Fe2O3 represent similar but different effects on the structure and properties of aluminosilicate system. Molecular dynamics was conducted to clarify the influences of FeO and Fe2O3 on the structure and properties of SiO2-CaO-Al2O3-FeO (Fe2O3) systems. The bond length and coordination number (CNs) of Si-O bond are almost not affected by FeO (Fe2O3), but FeO and Fe2O3 have opposite effects on the CNs of Al-O bond. The more the Fe3+ ion is, the closer the CN is to 4. The ability of Fe3+ ions to reduce bridging oxygen (BO) is greater than that of Fe2+ ions, while non-bridging oxygen (NBO) and free oxygen (FO) show an opposite trend. In the same way, the influence of Fe atomic numbers of different valence on BO, NBO and FO is similar to that of FeO (Fe2O3) on BO, NBO and FO. The total diffusion coefficient and viscosity of the system increase with the addition of iron oxide.