Asian Journal of Applied Chemistry Research

In this paper, we present the results of a molecular dynamics simulation for SiO₂ liquid to study the correlation between structural and dynamics heterogeneity. The evolution of structural changes at higher temperatures has been analyzed through the help of the SiO_x- and OSi_y units/clusters, bond angle distribution, Voronoi polyhedrons features and specified set of atoms. The result shows that SiO₂ liquid comprises a tetrahedral-network, some small SiO₅-, SiO₆-clusters and boundary region atoms which strongly depends on temperature. As temperature increases, the SiO₄-, SiO₅- and SiO₆ units become more distorted. Voronoi polyhedrons radius distribution of atoms is well fitted to a Gaussian form. We investigate the 10% most mobile (SMA) and 10% most immobile (SIMA) atoms in the system. We found that mobile or immobile atoms are non-uniformly distributed, forming spatially distinct mobile and immobile regions. These atoms form clusters whose size grows rapidly with temperature decreasing. The self diffusion pathway is explained by the movement of the small SiO_x-clusters, and bond-breaking Si-O in tetrahedral-network to form SiO₅-, SiO₆ clusters and boundary region atoms distributed heterogeneously (DH) in the network-forming liquid.