Molecular-Dynamics Study of Amorphous SiO_2 Relaxation

摘要

Using Molecular-Dynamics simulation we observed the generation of amorphous SiO_2 target from a randomly distributed Si and O atoms. We applied a sequence of annealing of the target with various temperature and quenching to room temperature. The relaxation time required by the system to form SiO_4 tetrahedral mesh after a relatively long simulation time, is studied. The final amorphous target was analyzed using the radial distribution function method, which can be compared with the available theoretical and experimental data. We found that up to 70% of the target atoms form the tetrahedral SiO_4 molecules. The number of formed tetrahedral increases following the growth function and the rate of SiO_4 formation follows Arrhenius law, depends on the annealing temperature. The local structure of amorphous SiO_2 after this treatment agrees well with those reported in some literatures.