High-temperature surface oxidation of the decagonal AlCoNi quasicrystal

Oxygen-induced surface faceting of the threefold-symmetry surface of icosahedral AlPdMn quasicrystal

“…The polar-angle profiles of the diffraction spots suggest a lateral domain size of at least 100 Å. Apparently, there is no constraint on the domain size, a phenomenon which results from the large interfacial strain usually encountered in quasicrystal-crystal junctions [4,5,7,8]. We note that for the oxide layers grown on the pentagonal surface of i-AlPdMn, the interfacial strain was lowered by the formation of a surface reconstruction on the oxide domains [7], thus, producing several minor diffraction spots evenly distributed over the LEED screen.…”

“…Recently, the selective oxidation of quasicrystals has contributed a further interesting surface phenomenon [4][5][6][7][8]. Metal oxide interfaces are of great interest for many technological applications, in particular, are ideally suited as model catalysts [9].…”

“…Recent studies [7,8] on the oxidation behavior of the pentagonal surface of icosahedral AlPdMn and the decagonal surface of AlCoNi quasicrystals facilitate the interpretation of the oxide layers in terms of a hexagonal domain structure. The results show that, compared to single crystals, the quasicrystalline atomic ordering on the surface alters the oxide domain structure during formation such that the domains remain in the nanometer-size and locally commensurate with the quasicrystal substrate symmetry.…”

“…The small size of the oxide domains is determined by a large interfacial strain energy, which is usually encountered in quasicrystal-crystal interfaces [5]. Further, the oxide layers grown on icosahedral AlPdMn reconstruct in order to lower the interfacial strain energy [7], while the layers grown on decagonal AlCoNi are strongly influenced by the topology of the decagonal surface ordering [8].…”

EVOLUTION OF THE PHASES OF QUASICRYSTALLINE ALLOYS ICOSAHEDRAL/ DECAGONAL Al62.2Cu25.3 Fe12.5/Al65Ni15Co20 AND OXIDATIVE BEHAVIOR

“…Studies that were performed with the decagonal phase in relation to AlCu-Co alloy formation revealed that they have a CsCl-type cubic phase and have bright symmetrical features around the decagonal phase; sequential Al 2 Cu intermetallic occurs with gray regions between the grains 8 .…”