First-principles study of low-index surfaces of the Al₅Co₂ complex metallic alloy

Abstract

The atomic and electronic structures of the (100) and (001) surfaces of the Al₅Co₂ complex metallic alloy are studied by ab initio calculations. The relative stability of the possible surface planes built from bulk truncation is calculated and the influence of the atomic surface density, the interlayer spacing and the surface chemical composition on the plane selection is discussed. In addition, we show that the simulated images of scanning tunnelling microscopy for each possible termination present a specific signature that appears to be sufficient to experimentally identify the surface plane.

Keywords:

• surfaces
• first-principles calculations
• electronic structure
• Al₅Co₂
• complex metallic alloy

Acknowledgements

The European Network of Excellence on ‘Complex Metallic Alloys’ (NMP3-CT-2005-500145), and the ‘Agence Nationale de la Recherche’ (ANR-08-BLAN-0041-01) are thanked for their financial support. Computing time was partially supplied by the ‘Institut Français Développement et de Recherche en Informatique Scientifique’ in Orsay (project 99642). SAV thanks INC-CNRS and the ‘Région Lorraine’ for financial support during his PhD thesis.