A new structural model of an Al72Ni20Co8 decagonal quasicrystal is constructed on the basis of high-angle annular dark-field images and high-resolution electron microscope images. The model is composed of two types of atom clusters with about a 0.4 nm radius as basic structural units, which are similar to the unit existing in the Al13Fe4 monoclinic approximant. The two clusters are located at the lattice points of the rhombic Penrose lattice. The model satisfies the symmetry of space group P105/mmc. High-resolution electron microscope images calculated from the model agree well with the experimental ones.
- AlFe monoclinic approximant
- Decagonal quasicrystal
- High-angle annular dark-field imaging
- Structural model
- Z-contrast imaging