Advertisement

Segregation and Ordering at a Ni-10 at.% Al Surface from First Principles

  • T. C. Schulthess
  • R. Monnier

Abstract

We have calculated the surface energy and work function of the (111) surface of Ni-10 at.% Al, as a function of the Al concentration in the first lattice plane, by means of the coherent potential approximation (CPA) for inhomogeneous systems, implemented within the layer Korringa-Kohn-Rostoker (LKKR) multiple scattering formalism. Our treatment includes the charge correlation ignored in the standard single-site implementation of the CPA. Temperature effects are accounted within the mean field approximation for the configurational entropy. We find that at 1000 K the surface concentration of Al is doubled with respect to its bulk nominal value, in agreement with the results of recent surface ion scattering experiments. Allowing the formation of an ordered L12 plane at the surface further lowers the free energy of the system.

Keywords

Interface Region Coherent Potential Approximation Random Alloy Binary Solid Solution Charge Correlation 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1.
    T. C. Schulthess, E. Wet, li, and M. Erbudak, Surf. Sc,. 320, L95 (1994).Google Scholar
  2. 2.
    T. M. Massalsky (editor), Binary Alloy Phase Diagrams, ( ASM International, USA, 1990 ).Google Scholar
  3. 3.
    D. D..Tohnson and F. J. Pinski, Phys. Rev. B 48. 11 553 (1993).Google Scholar
  4. 4.
    R. M. Dreizler and E. K. U. Gross, Density Functional Theory ( Springer-Verlag, Berlin, 1990 ).CrossRefGoogle Scholar
  5. 5.
    R. Magri, S. H. Wei, and A. Zunger, Phys. Rev. B 42, 11338 (1990).CrossRefGoogle Scholar
  6. 6.
    J. P. Perdew and R. Monnier, J. Phys. F 10, L287 (1980).Google Scholar
  7. J. M. MacLaren, S. Crampin, D. D. Vedensky. and J. B. Pendry, Phys. Rev. B 40. 12 164 (1989); S. Crampin et al., Phys. Rev. B 45, 464 (1992).Google Scholar
  8. 8.
    H. L. Skiver and N. M. R.osengaard. Phys. Rrv. B 43. 9538 (1991).CrossRefGoogle Scholar
  9. 9.
    S. Crampin, J. Phys.: Condens. Matter 5. L443 (1993).CrossRefGoogle Scholar
  10. 10.
    N. M. Rosengaard, private comunication.Google Scholar

Copyright information

© Springer Science+Business Media New York 1998

Authors and Affiliations

  • T. C. Schulthess
    • 1
  • R. Monnier
    • 2
  1. 1.Oak Ridge National LaboratoryOak RidgeUSA
  2. 2.Laboratorium für FestkörperphysikETH-HönggerbergZürichSwitzerland

Personalised recommendations