Structural Investigation of the (001) Surface of the Al9Co2 Complex Metallic Alloy

Alarcón Villaseca, S.; Ledieu, J.; Serkovic Loli, Laura Natalia; Weerd, M.-C. de; Gille, Peter; Fournée, V.; Dubois, J.-M. and Gaudry, E. (2011): Structural Investigation of the (001) Surface of the Al9Co2 Complex Metallic Alloy. In: Journal of Physical Chemistry C, Vol. 115, No. 30: pp. 14922-14932

Abstract

We present a detailed study of the (001) surface of the Al9Co2 crystalusing both experimental methods and first-principles calculations basedon the density functional theory. Experimentally, the (1 x 1) low-energyelectron diffraction pattern combined with the composition determinedusing X-ray photoemission spectroscopy is consistent with a bulkterminated surface. In addition, scanning tunneling microscopy (STM)measurements highlights the presence of only one type of surfacetermination. Combining experimental results with electronic structurecalculations provides many arguments to correlate the observed surfacetermination with the dense pure aluminum layer present in the Al9Co2bulk structure: (i) calculations show that this termination presents alower surface energy compared to another conceivable terminationobtained also from bulk truncation, (ii) step height measurements areconsistent with calculated interlayer spacings, (iii) calculatedbroadened densities of states and simulated STM images are qualitativelyin agreement with the experimental photoelectron spectra and theexperimental STM images.

• Item Type: Journal article
• Faculties: Geosciences > Department of Earth and Environmental Sciences > Crystallography and Materials Science
• Subjects: 500 Science > 550 Earth sciences and geology
• Language: English