Abstract
It is shown that low-energy electron diffraction (LEED) patterns of the three high-symmetry surfaces (fivefold, threefold and twofold) of icosahedral Al-Pd-Mn are all compatible with quasicrystallinity, under specific conditions of preparation. This conclusion results from comparing symmetries of experimental surface LEED patterns with bulk X-ray diffraction data which are converted to the conditions of the LEED experiment. This conclusion is also based upon an analysis of relative diffraction spot spacings in LEED. Hence, none of the three surfaces exhibits a massive lateral reconstruction, i.e. massive deviation from quasicrystallinity. The LEED pattern of the fivefold surface is distinct from the LEED pattern of the pseudo-tenfold surface of an orthorhombic approximant. We believe that this rules out the possibility that the fivefold surface of the icosahedral quasicrystal reconstructs to an approximant with tenfold or pseudo-10-fold symmetry. The twofold and threefold surfaces facet more readily, indicating qualitatively that they are less stable than the fivefold surface.
Original language | English |
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Pages (from-to) | 1-11 |
Number of pages | 11 |
Journal | Surface Science |
Volume | 450 |
Issue number | 1-2 |
DOIs | |
State | Published - Apr 1 2000 |
Externally published | Yes |
Funding
M. Quiquandon and J.M. Dubois provided valuable comments and suggestions. This work was supported by the Director, Office of Energy Research, Office of Basic Energy Sciences, Materials Sciences Division, of the U.S. Department of Energy under Contracts No. DE-AC03-76SF00098 and W-405-Eng-82.
Funders | Funder number |
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Materials Sciences Division | |
Office of Energy Research | |
U.S. Department of Energy | W-405-Eng-82, DE-AC03-76SF00098 |
Basic Energy Sciences |
Keywords
- Alloys
- Aluminum
- Low energy electron diffraction (LEED)
- Metallic surfaces