Pressure-induced structural and dynamic transitions in stimulated liquid aluminosilicate nanoparticles

Abstract

We have investigated the pressure-induced structural and dynamic transitions in liquid aluminosilicate (Al2O32SiO2) nanoparticles with a molecular dynamics (MD) method. Simulations were performed in spherical models under non-periodic boundary conditions containing 2596 ions with the Born–Mayer type pair potentials. In order to study the structural and dynamic changes, the models of liquid aluminosilicate nanoparticles have been built at densities ranging from 2.60 g cm−3, corresponding to the size of 4 nm, to the density of 4.2 g cm−3 at a temperature of 4200 K. The microstructure of the liquid nanoparticles has been analysed in detail through the coordination number distribution, bond-angle distribution and interatomic distances. We found a clear evidence of transition from the low density state (LDS) to high density state (HDS) structure in the models upon compression, like that observed in the bulk counterparts. This transition is accompanied by an anomalous diffusion of Al and Si atoms in the systems. Moreover, we also show the surface distribution properties in order to highlight the surface effects on dynamics upon compression.