The atomic structure and chemical ordering of Al65Ru25Cu20 quasicrystals was studied by anomalous-x-ray-diffraction measurements of powder samples carried out at the Ru and Cu K edges. The differential atomic pair distribution function of Ru, and partial structure factor of Ru and Cu, were obtained. The results suggest that a strong covalent bonding between Al and Ru is contributing to the stability of this phase. A structural model obtained by a direct projection of a six-dimensional hypercubic lattice with the vertex decoration using a non-Penrose window is shown to account for the results quite well. Compositional ordering is specified by subdividing the window for each composition. The structure of this phasonless quasicrystal is fundamentally different from the structures of other quasicrystals with phasons.
ASJC Scopus subject areas
- Condensed Matter Physics