Evolution of structure of SiO2 nanoparticles upon cooling from the melt

TL;DR

This study uses molecular dynamics simulations to analyze how the atomic structure of spherical SiO2 nanoparticles evolves as they cool from the melt, revealing temperature-dependent structural changes and defect concentrations.

Contribution

It provides detailed insights into the temperature-dependent structural evolution and defect formation in SiO2 nanoparticles during cooling from the melt.

Findings

Significant structural changes occur with temperature

Core and surface structures differ during cooling

Defect concentration varies with temperature

Abstract

Evolution of structure of spherical SiO2 nanoparticles upon cooling from the melt has been investigated via molecular-dynamics (MD) simulations under non-periodic boundary conditions (NPBC). We use the pair interatomic potentials which have weak Coulomb interaction and Morse type short-range interaction. The change in structure of SiO2 nanoparticles upon cooling process has been studied through the partial radial distribution functions (PRDFs), coordination number and bond-angle distributions at different temperatures. The core and surface structures of nanoparticles have been studied in details. Our results show significant temperature dependence of structure of nanoparticles. Moreover, temperature dependence of concentration of structural defects in nanoparticles upon cooling from the melt toward glassy state has been found and discussed.