Molecular dynamic simulation of liquid Al2O3 under densification

Abstract

We show first that when the densification of liquid Al2O 3 occurs, the structure consists of identical units AlOx and blocks OAly. Here x = 4, 5 and 6; y = 2, 3 and 4. Al 2O3 liquids with different densities and the same chemical composition differ from each other only in the relative number of these units and blocks. Taking this into consideration, we examine seven MD models with the density ranging from 2.7 to 3.3 g cm-3. The simulation shows that the volume of all constructed models is a linear function of the fraction of AlOx units. Furthermore, we observe the first sharp diffraction peak (FSDP) in the scattering structure factor S(q) located at q1 = 1.85-2.15 -1. The microscopic mechanism of densification and the origin of FSDP have been studied and discussed here. © 2009 IOP Publishing Ltd.