Molecular dynamics simulations of supercooled and amorphous Co100-xZrx: Atomic mobilities and structural properties

Molecular dynamics simulations are reported on Co100-xZrx in the complete r ange of compositions. The simulations are based on Hausleitner-Hafner poten tials. For the glassy states of the alloys, a comparison of simulated pair- correlation functions with experimental data is presented. Diffusivities we re evaluated for the liquid and supercooled melt from isothermal simulation runs. Therefrom a strong dependency on alloy composition is found for the critical temperature T-c(x) of the mode-coupling theory. Lines of constant averaged diffusivity in the supercooled melts scale closely with this tempe rature. The ratio of the component diffusivities shows a more involved vari ation with temperature and composition. These variations reflect difference s in the amorphous structure of the alloys, which are quantified in terms o f the chemical short-range-order at the level of tetrahedral clusters. PACS number(s): 61.20.Ja, 61.25.Mv, 64.70.Pf.