Structural modifications upon deposition of Fe on the icosahedral quasicrystal Al-Pd-Mn

We have deposited Fe on a clean pentagonal surface of an Al-Pd-Mn quasicrystal kept at ∼340 K. For low coverages, Fe diffuses into the bulk and destroys the quasicrystalline atomic order. At coverages higher than ∼0.8 nm, some Al is present in the film, which shows magnetic ordering. This is characteristic of only AlFe3 or Fe diluted with Al. This surface consists of five cubic domains in rotational alignment with the quasicrystalline substrate. For a film more than ∼1.6 nm thick, the Fe domains additionally show a tilting of 0.5° each. Removal of Fe by ion sputtering leaves the surface structure strongly modified due to depletion of Al as a result of alloying with Fe.