Local order and dynamic properties of liquid and undercooledCuxZr1−xalloys byab initiomolecular dynamics

Abstract

We report the results of first-principles molecular-dynamics simulations for liquid and undercooled ${\text{Cu}}_{x}{\text{Zr}}_{1\ensuremath{-}x}$ alloys at four different compositions. The local structure as defined by the partial pair-correlation functions and the Bhatia-Thornton partial structure factors is found to display a strong evolution as a function of composition. In addition, a structural analysis using three-dimensional pair-analysis techniques evidences an icosahedral short-range order much more pronounced around ${x}_{\text{Cu}}=0.64$. In examining the dynamic properties of these alloys, we show a strong interplay between the structural changes and the evolution of the viscosity as a function of composition.