Structure and dynamics of liquid Ni36Zr64 by ab initio molecular dynamics

First-principles molecular dynamics simulations are performed to investigate the interplay between the local structure and atomic dynamics of liquid Ni36Zr64 eutectic alloy in the equilibrium and undercooled states. The topological and chemical short-range orders (SROs) as characterized by the partial pair-correlation functions show good agreement with recent neutron-scattering experiments. Three-dimensional structural analysis shows that the local environment around both Ni and Zr atoms is more complex than the icosahedral SRO due to the frustration of icosahedra driven by the strong directional interaction and large size difference between Ni and Zr. The atomic dynamics analysis shows that the Ni-centered < 0,2,8,1,0 > and Zr-centered < 0,1,10,4,0 > Voronoi polyhedra with relatively longer lifetime play a key role in slowing down the dynamics. The fraction of these clusters increases significantly as the liquid is cooled down and thus facilitates glass formation in the rapidly quenched alloys.