Understanding formation mechanism of ZnO diatomic chain and multi-shell structure using physical mechanics: Molecular dynamics and first-principle simulations?

Abstract

In this paper, the possibility of the monatomic chain (MC) formation for ZnO material was studied by molecular dynamics (MD) simulation. The process of MC formation and the effects of temperature, strain rate and size were studied extensively. The tensile process can be divided to be five stages and the ZnO diatomic chain (DC) can be found. The MD results show that most atoms in MC came from the original surface of ZnO nanowires (NWs). Temperature and strain rate are two important factors affecting the process, and both high temperature and low strain rate in a certain range would be beneficial to the formation of DC. Moreover, the effects of strain rate and temperature could attribute to the Arrhenius model and the energy release mechanism. Furthermore, multi-shell structure was found for the samples under tensile strain and the layer-layer distance was about 3 Å. Our studies based on density functional theory showed that the most stable structure of ZnO DC was confirmed to be linear, and the I–V curve was also got using ATK.