Journal of Chemical Physics
Feedback | Help | Exit
The Journal of Chemical Physics
Search:
   
 
 
 
Previous Article
Reactions of atomic hydrogen with the Si(111) (7×7) surface by high resolution electron energy loss spectroscopya)
High resolution electron energy loss spectroscopy (vibrational and electronic excitations) and monochromatic low-energy electron diffraction (LEED) have been applied to the study of atomic-hydrogen ad...
Next Article
The interaction of CO and Pt(100). II. Energetic and kinetic parameters
We have investigated the mechanism and driving force of the CO-induced phase transition of the Pt(100) surface. In a preceding paper, we have concentrated on the mechanism by which CO removes the surf...

The interaction of CO and Pt(100). I. Mechanism of adsorption and Pt phase transition

J. Chem. Phys. 78, 7437 (1983); doi:10.1063/1.444734

Issue Date: 15 June 1983

You are logged in to this journal.

R. J. Behm, P. A. Thiel, P. R. Norton, and G. Ertl
Institut für Physikalische Chemie der Universität München, Sophienstrasse 11, D-8000 München 2, Federal Republic of Germany
It is known that clean Pt(100) normally exists in a reconstructed (``hex'') phase, that a metastable clean unreconstructed phase [the (1×1)] can be prepared, and that during adsorption of CO the hex-->(1×1) transition occurs. In this and the following paper, we describe an investigation of the CO/Pt(100) system which clarifies the mechanism of this adsorbate-induced Pt phase transition. The experimental techniques included fast video-LEED techniques, thermal desorption spectroscopy, electron energy loss spectroscopy, and work function measurements. Adsorption of CO at low temperature (T<~400 K) is discussed in this paper. CO on (1×1)-Pt forms a c(2×2) overlayer near and at the ideal coverage of theta=0.5, in which the CO molecules occupy on-top adsorption sites. Repulsive CO–CO interactions cause this structure to form. CO adsorption on hex-Pt proceeds via formation of small areas with the same local structure, a c(2×2) layer of CO on (1×1)-Pt, even when the total coverage of CO is low (0.05<theta<0.5). This comparison between adsorption on the two phases indicates that the mechanism of the hex-->(1×1) transition involves, effectively, ``island'' formation of adsorbed CO in spite of the repulsive character of the CO–CO interaction in the c(2×2). This apparent contradiction is resolved by considering the energy contribution of the Pt phase transition which accompanies the island formation, the whole process being well described as a ``nucleation and trapping'' mechanism. The nucleation process strongly limits the long-range order of the CO: At theta=0.5, the c(2×2) domains which result from CO adsorption on (1×1) are about five times larger than for hex-Pt, even though in the latter case, the substrate has been completely converted to (1×1)-Pt at theta=0.5. Differences in the long-range order of CO at theta>=0.5 are also observed in the surface work functions and in the distributions of occupied adsorption sites. The Journal of Chemical Physics is copyrighted by The American Institute of Physics.
History: Received 28 December 1982; accepted 3 March 1983
Permalink: http://link.aip.org/link/?JCPSA6/78/7437/1
FULL TEXT OPTIONS   (FREE)
Download PDF (968 kB) View Cart

KEYWORDS and PACS

Keywords
PACS
  • 82.65.My
    Physical chemistry Surface processes Sorption and accommodation coefficients
  • 68.45.By
    Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties) Solidfluid interface processes Sorption equilibrium
  • 82.65.Dp
    Physical chemistry Surface processes Thermodynamics of surfaces
  • 64.70.Kb
    Equations of state, phase equilibria, and phase transitions Phase equilibria, phase transitions, and critical points of specific substances Solidsolid transitions
  • YEAR: 1983

PUBLICATION DATA

ISSN:
0021-9606 (print)   1089-7690 (online)
Publisher:
AIP is a member of CrossRef AIP

REFERENCES (46)
View in Separate Window/Tab
  1. G. Ertl, P. R. Norton, and J. Rüstig, Phys. Rev. Lett. 49, 177 (1982).
  2. P. R. Norton, J. A. Davies, D. K. Creber, C. W. Sitter, and T. E. Jackman, Surf. Sci. 108, 205 (1981). [Inspec] [ISI] [ChemPort]
  3. K. Heinz, E. Lang, K. Strauss, and K. Müller, Appl. Surf. Sci. 11/12, 611 (1982).
  4. K. Heinz, E. Lang, K. Strauss, and K. Müller, Surf. Sci. 120, L401 (1982). [Inspec] [ISI] [ChemPort]
  5. M. A. Van Hove, R. J. Koestner, P. C. Stair, J. P. Bibérian, L. L. Kesmodel, I. Bartoš, and G. A. Somorjai, Surf. Sci. 103, 189 (1981), and references therein. [Inspec]
  6. P. Heilmann, K. Heinz, and K. Müller, Surf. Sci. 83, 487 (1979). [Inspec] [ISI] [ChemPort]
  7. M. A. Van Hove, R. J. Koestner, P. C. Stair, J. P. Bibérian, L. L. Kesmodel, I. Bartoš, and G. A. Somorjai, Surf. Sci. 103, 218 (1981). [Inspec] [ISI] [ChemPort]
  8. A. E. Morgan and G. A. Somorjai, J. Chem. Phys. 51, 3309 (1969); [ISI] [ChemPort]
    9. Surf. Sci. 12, 405 (1968). [Inspec]
  9. M. A. Barteau, E. I. Ko, and R. J. Madix, Surf. Sci. 102, 99 (1981). [Inspec] [ISI] [ChemPort]
  10. H. P. Bonzel and G. Pirug, Surf. Sci. 62, 45 (1977). [Inspec] [ISI] [ChemPort]
  11. J. A. Davies, T. E. Jackman, D. P. Jackson, and P. R. Norton, Surf. Sci. 109, 20 (1981). [Inspec] [ISI]
  12. P. A. Thiel, R. J. Behm, P. R. Norton, and G. Ertl, Surf. Sci. 121, L553 (1982). [Inspec] [ISI] [ChemPort]
  13. J. W. Christiansen, The Theory of Transformations in Metals and Alloys (Pergamon, Oxford, 1975);
    14. H. Haken, Synergetics (Springer, Berlin, 1977).
  14. P. A. Thiel, R. J. Behm, P. R. Norton, and G. Ertl, J. Chem. Phys. 78, 7448 (1983). [ChemPort]
  15. H. Froitzheim, H. Ibach, and S. Lehwald, Rev. Sci. Instrum. 46, 1325 (1975). [ISI] [ChemPort]
  16. H. Herz, H. Conrad, and J. Küppers, J. Phys. E 12, 369 (1979). [Inspec] [ChemPort]
  17. E. Lang, P. Heilmann, G. Hanke, H. Heinz, and K. Müller, Appl. Phys. 19, 287 (1979). [Inspec] [ChemPort]
  18. R. J. Behm and G. Ertl (in preparation).
  19. G. Brodén, G. Pirug, and H. P. Bonzel, Surf. Sci. 72, 45 (1978). [Inspec] [ChemPort]
  20. C. R. Helms, H. P. Bonzel, and S. Kelemen, J. Chem. Phys. 65, 1773 (1976). [ISI] [ChemPort]
  21. C. W. Tucker, Surf. Sci. 2, 516 (1964).
  22. A. Crossley and D. A. King, Surf. Sci. 95, 131 (1980). [Inspec] [ISI] [ChemPort]
  23. R. W. McCabe and L. D. Schmidt, Surf. Sci. 66, 101 (1977). [Inspec] [ChemPort]
  24. G. Pirug, H. Hopster, and H. Ibach, Ned. Tjdschr. Vakuumtech. 16, 152 (1978).
  25. P. R. Norton, J. W. Goodale, and E. B. Selkirk, Surf. Sci. 83, 189 (1979); [Inspec] [ISI] [ChemPort]
    26. G. Ertl, M. Neumann, and K. M. Streit, ibid. 64, 393 (1977); [Inspec] [ISI] [ChemPort]
    K. Horn and J. Prltchard, J. Phys. (Paris), Colloq. Suppl. No. 10.38, 14, 164 (1977).
  26. D. A. King, Surf. Sci. 47, 384 (1975), and references therein.
  27. S. R. Kelemen, T. E. Fischer, and J. A. Schwartz, Surf. Sci. 81, 440 (1979). [Inspec] [ISI]
  28. P. J. Kisliuk, J. Chem. Phys. Solids 3, 95 (1957);
    29. also 5, 78 (1958).
  29. M. Oku, R. J. Behm, and C. R. Brundle (in preparation).
  30. R. J. Behm, K. Christmann, G. Ertl, and M. A. Van Hove, J. Chem. Phys. 73, 2984 (1980). [ChemPort]
  31. C. T. Campbell, G. Ertl, H. Kuipers, and J. Segner, Surf. Sci. 107, 207 (1981). [Inspec] [ISI] [ChemPort]
  32. G.-C. Wang, in The Chemical Physics of Solid Surfaces and Heterogeneous Catalysis, edited by D. A. King and D. P. Woodruff (Elsevier, New York, 1982).
  33. G.-C. Wang, Ph.D dissertation, University of Wisconsin-Madison, 1978.
  34. R. L. Park, J. E. Houston, and D. G. Schreiner, Rev. Sci. Instrum. 42, 60 (1971). [ISI]
  35. R. Imbihl, R. J. Behm, K. Christmann, G. Ertl, and T. Matsushima, Surf. Sci. 117, 257 (1982).
  36. Monte Carlo Methods in Statistical Physics, edited by K. Binder (Springer, Berlin, 1979).
  37. A. M. Bradshaw and F. M. Hoffmann, Surf. Sci. 72, 513 (1978). [Inspec]
  38. S. Andersson, Solid State Commun. 21, 75 (1977). [Inspec] [ISI] [ChemPort]
  39. J. C. Tracy, J. Chem. Phys. 56, 2736 (1972). [ISI] [ChemPort]
  40. J. C. Tracy and P. W. Palmberg, J. Chem. Phys. 51, 4852 (1969). [ISI] [ChemPort]
  41. E. D. Williams, A. C. Sobrero, and W. H. Weinberg, J. Chem. Phys. 77, 1156 (1982);
    42. H. Pfnür, P. Feulner, and D. Menzel, ibid. (submitted).
  42. R. J. Behm, K. Christmann, G. Ertl, M. A. van Hove, P. A. Thiel, and W. H. Weinberg, Surf. Sci. 88, L59 (1979).
  43. H. Froitzheim, H. Hopster, H. Ibach, and S. Lehwald, Appl. Phys. 13, 147 (1977). [Inspec] [ChemPort]
  44. W. Erley, H. Wagner, and H. Ibach, Surf. Sci. 80, 612 (1979). [Inspec] [ISI] [ChemPort]
  45. R. Brooks, N. V. Richardson, and D. A. King, Surf. Sci. 117, 434 (1982). [Inspec] [ChemPort]
  46. M. A. Barteau, E. I. Ko, and R. J. Madix, Surf. Sci. 104, 161 (1981). [ISI] [ChemPort]

Copyright © American Institute of Physics