Evaluation of the local environment for nanoscale quasicrystal formation in Zr₈₀Pt₂₀ glassy alloy using Voronoi analysis

The local atomic structure of nano-quasicrystal-forming Zr ₈₀Pt₂₀ binary glassy alloy was investigated by reverse Monte Carlo modeling based on the results of x-ray diffraction. A prepeak at Q∼17nm^-1 originating from the unique bonding between the Pt-Pt pair is observed in the structure factor. Voronoi analysis indicates that an icosahedral-like polyhedron is formed around Pt. It is also found that icosahedral-like polyhedra exist around Zr; however, the fraction of perfect icosahedra is considerably lower than that in the nano-quasicrystalforming Zr₇₀Pd₃₀ glassy alloy. A difference in the local environment between the two binary quasicrystal-forming glassy alloys is suggested.