Abstract
A six-dimensional cluster model of icosahedral Al-Pd-Mn quasicrystals used in the recent structure refinement is described in detail. This model is based on five kinds of clusters located at vertices, edge centers of the inflated three-dimensional Penrose pattern (3DPP) with an edge length of about 20 Å, and two body-diagonal positions of each acute rhombohedron. Two kinds of 20 Å clusters, one of which is seen in are located at even- and odd-parity 12-fold vertices of the inflated 3DPP. This is proved to give small R factors for 493 independent reflections and leads to the 1/1 and 2/1 approximant structures of and by introducing appropriate cubic phason strains and taking a three-dimensional cut.
- Received 30 October 2002
DOI:https://doi.org/10.1103/PhysRevB.68.094201
©2003 American Physical Society