Spatial correlations of most mobile or immobile particles in supercooled Al₂O₃

Abstract

Spatial correlations of most mobile and immobile particles in supercooled Al 2 O 3 model at the temperatures of 2100 K have been investigated by using molecular dynamics (MD) method. Simulations were done in the basic cube under periodic boundary conditions containing 3000 ions with Born -Mayer type pair potentials. We evaluate the non-Gaussian parameter for the self-part of the van Hove correlation function, atomic displacement distribution (ADD) and cluster-size distributions of most mobile and immobile particles in the model. We compare the partial radial distribution functions (PRDFs) for the 5% most mobile or immobile Al, O particles with the corresponding mean ones. We have found that mean cluster size grows with decreasing temperature. The composition evolution in subset of most mobile or immobile particles upon cooling and annealing was obtained and presented. The relation between local structure and dynamics in the system has been studied and discussed.

Composition dependence of static and dynamic heterogeneities in simulated liquid aluminum silicates

“…[20][21][22][44][45][46] This problem has been tested again for our aluminum silicates and the same tendency has been found. We show the probability distribution P͑n͒ of clusters of size n for the 10% most mobile and immobile particles in liquid models obtained at 2800 K in Fig.…”

“…20 Likely, calculations showed that the most mobile or immobile particles in supercooled Al 2 O 3 are strongly correlated, they formed clusters, and the mean cluster size increases with decreasing temperature. 21,22 A possible relation between particle mobility and local structural defects in the system was found but no relation between particle mobility and local environment of the particles unlike those observed in Lennard-Jones liquids. 23 Therefore, systematic analysis of the dependence of microstructure and dynamics, including diffusion and DH, on Al 2 O 3 content in aluminum silicates is our main aim here.…”

“…[18][19][20][21][22] In order to detect the DH in liquid aluminum silicates, we have determined the non-Gaussian parameter of Al, Si, and O particles in liquid models obtained at 2800 K. The nonGaussian parameter has the form:…”

Diffusion and dynamical heterogeneity in simulated liquid SiO2under high pressure

“…Dynamical heterogeneity (DH) in different supercooled systems at ambient pressure has been under intensive investigation in recent years (see [18][19][20][21][22][23][24][25][26][27][28][29][30] and references therein). In particular, DH in BKS interatomic potential silica models has been studied in detail [21][22][23].…”