Structural Study of Zr₅₀Cu₅₀ Amorphous Alloy by Anomalous X-ray Scattering Coupled with Reverse Monte-Carlo Simulation

Abstract

Anomalous X-ray scattering (AXS) analysis was applied for the structural analysis of a rapidly quenched Zr₅₀Cu₅₀ amorphous alloy. The present AXS analysis provided the environmental structural information round Cu and Zr, and the subsequent reverse Monte Carlo (RMC) simulation allowed us to obtain three partial pair distribution functions together with a three-dimensional structural model. The Voronoi polyhedral analysis of the nearest-neighbor region confirms that the structural features are similar to those of the dense random packing of hard spheres (DRPHS) model. The chemical oscillatory structure composed of alternating Cu-rich and Zr-rich coordination shells was realized in the middle range, up to 0.8 nm. The shell structure is suggested to be one of the fundamental structural features of medium-range ordering in the Zr₅₀Cu₅₀ amorphous alloy.