Atomic short-range order in an Al₇₂Ni₁₈Fe₁₀decagonal quasicrystal studied by anomalous x-ray scattering

Abstract

Diffuse scattering around Bragg reflections was observed by anomalous x-ray scattering in a single decagonal quasicrystal of Al72Ni18Fe10. Intensity modulations of the diffuse scattering were measured for four incident x-ray beam energies. Quantitative analysis of the diffuse scattering data shows the presence of atomic short-range order (SRO) in three kinds of pair-correlation functions: Al–Ni, Ni–Fe and Fe–Al. The SRO diffuse scattering is decomposed into each component by self-consistent calculation. Using Metropolis Monte Carlo simulations, the SRO diffuse scattering is calculated qualitatively using the SRO parameters. Asymmetric distributions of the diffuse scattering were seen along a longitudinal direction, even though the Al72Ni18Fe10 quasicrystal has quite small mosaicity.