Atomic arrangements in vapor quenched Pd₈₀Si₂₀ and Au₃₅Ni₆₅ amorphous alloys

Abstract

The structure of Pd80Si20 and Au35Ni65 alloys, vapor quenched onto substrates of NaCl held at liquid nitrogen temperatures is investigated by electron microscopy and scanning electron diffraction. The structure of the Pd80Si20 amorphous alloy is best described by a dense random packing of hard spheres model of two sphere sizes with no metalloids as nearest neighbours of each other. The PdPd nearest neighbour distance is 2.75 Å and the PdSi nearest neighbour distance is 2.65 Å. Coevaporated films of Au35Ni65 quenched onto liquid nitrogen temperatures are found to be amorphous. Their structure is successfully described by a dense random packing of hard spheres model of two sphere sizes with no chemical constraints on both the Au and Ni atoms. The NiNi nearest neighbour distance is 2.45 Å. The AuAu nearst neighbour distance is 2.85 Å and the AuNi distance is 2.65 Å. Copyright © 1980 WILEY‐VCH Verlag GmbH & Co. KGaA