Correlation between structural relaxation and connectivity of icosahedral clusters in CuZr metallic glass-forming liquids

Abstract

The correlation between structural relaxation and the medium-range structures formed by icosahedral cluster packing in CuZr supercooled metallic glass-forming liquids was studied via molecular dynamics simulations. We find that compared to the amount of icosahedral clusters, the medium-range structures formed by icosahedral cluster packing play more important and controlling roles in the structural relaxation process of the supercooled liquids. The relaxation times of local structures depend exponentially on the connectivity of local structures. Despite the argument whether there is a specific connection between the static structure and dynamic property of glass formers in particle level, it does exist on larger length scale. Our results demonstrate that dynamical heterogeneity is indeed correlated with the medium-range static atomic structures in the supercooled glass-forming liquids.