Glass forming ability and short-range order in a binary bulk metallic glass by <i>ab initio</i> molecular dynamics

We have performed a series of ab initio molecular dynamics simulations of Cu64Zr36 alloy, in order to study the glass forming ability in connection to the local order. The results show that Cu64Zr36 is characterized by a pronounced icosahedral short-range order (ISRO) in the liquid, undercooled, and amorphous states associated with the existence of Cu7Zr6 and Zr6Cu10 clusters centered by Cu and Zr atoms, respectively. The latter increase the structural incompatibility of liquid and amorphous states with competing crystalline phases and give support to the view that good glass formers have high degree of ISRO already present in the liquid.