Computational Insights Into the Influence of MgO and MnO on the Oxygen Network Structure and Transport Properties of the CaO‐SiO ₂ ‐P ₂ O ₅ System

This study uses molecular dynamics simulations to investigate the effects of varying MnO or MgO addition amounts (0–15 mass%) on the oxygen network structure and transport properties within the CaO‐SiO 2 ‐P 2 O 5 ‐MnO/MgO (CSPMn/Mg) system. The addition of MnO/MgO exhibits a negligible influence on the bond lengths between constituent atoms and oxygen in CSPMn/Mg systems. Specifically, Mg–O and Mn–O bond lengths remain stable at 2.06 and 2.18 Å, respectively. Both additives reduced the proportion of bridging oxygen while increasing nonbridging oxygen and free oxygen. Concurrently, they depolymerize highly aggregated structural units (Q 3 , Q 4 ) into low‐polymerization network‐forming monomers (Q 0 ). Compared with Mn 2+ , Mg 2+ exhibits higher field strength and oxygen affinity, leading to stronger depolymerization of Si–O–Si networks and higher diffusivity. Adding MnO or MgO to the CSP system will enhance the overall diffusion ability of O atoms, which is manifested macroscopically as a decrease in viscosity of the silicate phosphate framework system. With increasing MnO or MgO addition amounts, an increase in total enthalpy and a decrease in liquidus temperature of the system both reflect a heightened degree of structural disorder. These complementary structural and physicochemical properties ultimately demonstrate the depolymerization effect of adding MnO or MgO on the CSP system structure.