Philosophical Magazine B · 1985 · 344 citations · 6 references
Natural SciencesChemistryMaterials ScienceCrystal StructureInorganic ChemistryMaterials ChemistryCoordination NumberCrystal ChemistryCrystal LatticeCrystal SymmetryCrystallographyX-ray DiffractionAtomic Structure CalculationsCrystal Structure AnalysisCrystal Symmetry AnalysisIcosahedral SymmetryQuasi-crystalsQuasicrystal SymmetryQuasicrystalsThreefold Axes
Abstract A model is proposed for the atomic structure of the Al-Mn quasicrystal. Mn icosahedra are connected through their threefold axes, with a coordination number of seven and each bond defined by an octahedron. This Mn skeleton has icosahedral symmetry and its projections onto various planes have a self-similarity property based on the golden number, in agreement with TEM results. The filling up with A1 atoms determines a sublattice where empty Al icosahedra are connected by chains of three distorted octahedra. Two kinds of Mn-Al first-neighbour environments are distinguished, involving nine and ten Al atoms. Taking the ratio of the two Mn site numbers as equal to the golden number leads to a chemical composition in agreement with X-EDS analysis.
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Metallic Phase with Long-Range Orientational Order and No Translational Symmetry
D. Shechtman, I. A. Blech, D. Gratias et al. · Physical Review Letters · 1984 · 7K citations · Full text
Quasicrystals: A New Class of Ordered Structures
Dov Levine, Paul J. Steinhardt · Physical Review Letters · 1984 · 2.1K citations · Full text