Measurement of Non-Equilibrium Diffusion from Two-Dimensional Ordering Kinetics

  • M. G. Lagally
  • M. C. Tringides
Conference paper
Part of the Springer Series in Surface Sciences book series (SSSUR, volume 14)

Abstract

The thermodynamic behavior of an overlayer on a surface is determined by the microscopic interactions between the adsorbate atoms and between adsorbate and substrate atoms. A determination of these microscopic interactions can be made at equilibrium or also as the system evolves toward equilibrium. The usual equilibrium determination is a measurement of the temperature-coverage phase diagram of the overlayer, for example, with a diffraction or specific-heat experiment. Using a statistical model with a few local interaction parameters and an underlying lattice geometry, the phase boundaries are fitted to determine the magnitude of the interaction parameters. Nonequilibrium determinations of the same interactions can also be made. A system that is initially in an equilibrium state Xi is suddenly forced into a different state (for example, by a temperature or chemical potential quench) where its equilibrium state is Xf. The evolution of the system toward Xf requires mass transport, which can be monitored through a measurement of the change in order of the system with time. The temperature and coverage dependence of the ordering provides information on the microscopic interactions that govern non-equilibrium diffusion in the system.

Keywords

Activation Energy Growth Exponent Coverage Dependence Equilibrium Diffusion Surface Imperfection 
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.
This is a preview of subscription content, log in to check access.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1.
    R. Gomer, Surface Sci. 38, 373 (1973)CrossRefGoogle Scholar
  2. 2.
    J. R. Chen and R. Gomer, Surface Sci. 79, 413 (1979)CrossRefGoogle Scholar
  3. 3.
    M. Tringides and R. Gomer, Surface Sci. 155, 254 (1985)CrossRefGoogle Scholar
  4. 4.
    M. C. Tringides, P. K. Wu, and M. G. Lagally, In: Proceedings of the Second Campobello Conference, 1987, ed. by H. J. Kreuzer (Springer, Berlin, Heidelberg 1988) (in press).Google Scholar
  5. 5.
    P. K. Wu, M. C. Tringides, and M. G. Lagally, Phys. Rev. (submitted).Google Scholar
  6. 6.
    G.-C. Wang, T.-M. Lu, and M. G. Lagally, J. Chem. Phys. J59, 479 (1978)CrossRefGoogle Scholar
  7. 7.
    H. G. Lagally, T.-M. Lu, and G.-C. Wang, In: Ordering in Two Dimensions, ed. by S. Sinha (Elsevier, New York 1980).Google Scholar
  8. 8.
    E. D. Williams, S. C. Cunningham, and W. H. Weinberg, J. Chem. Phys. 68, 4688 (1978).CrossRefGoogle Scholar
  9. 9.
    M. C. Tringides, P. K. Wu, and M. G. Lagally, Phys. Rev. Letters 59, 315 (1987).CrossRefGoogle Scholar
  10. 10.
    S. M. Allen and J. W. Cahn, Acta Metall. 27, 1085 (1979).CrossRefGoogle Scholar
  11. 11.
    I. M. Lifshitz and V. V. Slyozov, J. Chem. Phys. Solids J.9, 35 (1961).CrossRefGoogle Scholar
  12. 12.
    A. Sadiq and K. Binder, J. Stat. Phys. 35, 617 (1984).CrossRefGoogle Scholar
  13. 13.
    P. A. Rikvold, K. Kaski, and J. D. Gunton, Phys. Rev. B29, 6285 (1984).Google Scholar
  14. 14.
    M. C. Tringides and M. G. Lagally, in preparation.Google Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 1988

Authors and Affiliations

  • M. G. Lagally
    • 1
  • M. C. Tringides
    • 1
  1. 1.University of WisconsinMadisonUSA

Personalised recommendations