Addou, R.; Gaudry, E.; Deniozou, Th.; Heggen, M.; Feuerbacher, M.; Gille, Peter; Grin, Yuri; Widmer, Roland; Gröning, Oliver; Fournée, V.; Dubois, J.-M.; Ledieu, J.
Structure investigation of the (100) surface of the orthorhombic Al13Co4 crystal.
In: Physical Review B, Vol. 80, Nr. 1
Volltext auf 'Open Access LMU' nicht verfügbar.
We present a detailed study of the (100) surface of the orthorhombicAl13Co4 crystal using both experimental and ab initio computationalmethods. This complex metallic alloy is an approximant of the decagonalAl-Ni-Co quasicrystalline phase. After sputter-annealing preparation ofthe surface at 1073 K, the low-energy electron diffraction patternrecorded exhibits a pseudotenfold symmetry with lattice parametersconsistent with those of the bulk model. At this stage, scanningtunneling microscopy (STM) measurements reveal two different types ofsurface terminations. A comparison between these two surface structuresand the bulk planes indicate that the terminations correspond either toan incomplete puckered layer (P) or to an incomplete flat layer (F). At1173 K, the majority of the surface consists of P layer terminations.STM images calculated from our proposed surface model are in goodagreement with experimental images. X-ray photoelectron diffractionpatterns and single scattering cluster calculations further confirm thatthe local atomic arrangements present in the bulk model are preservedwithin the near-surface region.