Local Ordering And Interfacial Structure Between Spinel Crystal And Aluminosilicate Glasses From Molecular Dynamics Simulations

Molecular dynamics simulations were performed to investigate the interfaces of soda magnesia aluminosilicate glass and MgAl2O4 spinel crystals. The glass structures were first generated and characterised. It was found that the glass-forming network consists of fourfold coordinated [SiO4] and [AlO4] tetrahedra connected through corner sharing with Na+ and Ca2+ acting as modifiers or charge compensators. The glass and crystal interfaces were then constructed on low energy spinel surfaces with special measures to ensure two natural interfaces. The interfacial structures were characterised by z-density profile, pair distribution function and coordination number analysis. The results show that there exist local ordering on the glass side and preferential adsorption of specific cation near the interface.