New analysis characterizing the dynamics heterogeneity and microstructure in liquid silicates

Abstract

We use molecular dynamics simulation to study liquid silicates at ambient pressure and temperature of 3500 K. New analysis on structure and dynamics is carried out using such characteristics as the rate of bond-breaking events, link-cluster function and different subnet types. We found that the structural heterogeneity exists in short and medium length scales. Namely, the local environments of cations are quite different. The parking of SiOx in the silicate systems is also very different. Further, the simulation shows that during a moderate long time the melt has a two-domain structure consisting of separate immobile domains and a mobile domain. These domain types differ strongly in the atomic mobility and chemical composition. The simulation also gives clear evidences for dynamics heterogeneity (DH) in the melt and that the non-uniform spatial distribution of bond-breaking events is responsible for the DH.