Structure of the (010) surface of the orthorhombic complex metallic alloy T -Al 3 (Mn,Pd)
Résumé
The atomic and electronic structures of the 010 surface of the T-Al 3 Mn,Pd complex metallic alloy is investigated by means of low-energy electron diffraction LEED, scanning tunneling microscopy STM, x-ray and ultraviolet photoelectron spectroscopy XPS and UPS, x-ray photoelectron diffraction XPD, and ab initio calculations. While structural imperfections are observed at the surface and out of the various possible terminations, the puckered P2 layer is identified as the only surface termination, thus pointing out the existence of a well-defined minimum in the surface energy landscape. The measured step heights correspond to distances between identical planes along the 010 direction in the bulk model, i.e., b / 2. A bias dependency of the STM topography is found. The XPD and LEED patterns confirm the pseudotenfold symmetry of the sample. XPS and UPS show a more metallic signature of the T phase compared to Al-based quasicrystalline phases.
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