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Modification of the Properties of Metal Overlayers oN Nb(110) and Ta(1l0)

Published online by Cambridge University Press:  25 February 2011

M. W. Ruckman ,
Myron Strongin  and
Xiaohe Pan
M. W. Ruckman
Affiliation:
Brookhaven National Laboratory, Upton, NY 11973
Myron Strongin
Affiliation:
Brookhaven National Laboratory, Upton, NY 11973
Xiaohe Pan
Affiliation:
Brookhaven National Laboratory, Upton, NY 11973
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Abstract

Modification of the physical and chemical properties of noble and near-noble metal monolayer films supported on Nb(110) or Ta(l10) is demonstrated using photoemission and LEED. Strong adlayer-substrate bonding leads to the formation of commensurate Pd or Pt overlayers at low coverage (8 < 0.7 ML). Ni and Cu form incommensurate structures because the additional interfacial misfit cannot be overcome by substrate-overlayer bonding. Ag and Au form commensurate overlayers at coverages le ss than 3 ML because the lattice misfit is small. The strong overlayer-substrate bonding produces large changes in the chemical activity of near-noble metal overlayers. Photoemission measurements on Pt monolayers show that the hybridized metal d-states are shifted further below the Fermi level “EF” and show a reduction in the surface density of states at EF. This absence of bonding d-states near EF effects CO chemisorption. However, as additional layers of Pd and Pt are deposited, the d-occupancy at EF grows, with “constant” atomic structure and the amount of CO increases. Hence, in these systems chemisorption changes can be studied as a function of changing electronic structure while holding the surface structure fixed.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 83: Symposium J – Physical and Chemical Properties of Thin Metal Overlayers and Alloy Surfaces , 1986 , 85
Copyright
Copyright © Materials Research Society 1987

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References

REFERENCES

1. Sachtler, J. W., Van Hove, M. A., Biberian, J. P. and SomorJai, G. A., Phys. Rev. Lett. 45, 1601 (1980); Shen Xinyin, D. J. Frankel, J. S. Hermanson, G. J. Lapeyre and R. J. Smith, Phys. Rev. B32, 2120 (1985).Google Scholar
2. Houston, J. E., Peden, C. H. F., Blair, D. S. and Goodman, D. W., Surf. Sci. 167, 427 (1986).CrossRefGoogle Scholar
3. Bauer, E. and Van der Merwe, J. H., Phys. Rev. B 33, 3657 (1986).Google Scholar
4. Falicov, L. M. and Somorjai, G. A., Proc. Natl. Acad. Sci. (USA), 82, 2207 (1985).Google Scholar
5. Pauling, L., The Nature of the Chemical Bond, 3rd ed. (Cornell University Press, Ithaca, 1960).Google Scholar
6. Falco, C. M., Bennett, W. R. and Boufelfel, A. in Dynamical Phenomena at Surfaces, Interfaces and Superlattices, edited by Nizzoli, F., Rieder, K.-H. and Willis, R. F. (Springer-Verlag, Berlin, 1985) p. 35.Google Scholar
7. Smith, R. J., Phys. Rev. B 21, 3131 (1980); iR. J. Smith, G. P. Williams, J. Colbert, M. Sagurton and G. J. Lapeyre, Phys. Rev. B22, 1584 (1980).CrossRefGoogle Scholar
8. Sagurton, M., Strongin, M., Jona, F. and Colbert, J., Phys. Rev. B 28, 4075 (1983).Google Scholar
9. Pan, Xiaohe, Ruckman, M. W. and Strongin, Myron, Phys. Rev. B (submitted).Google Scholar
10. El-Batanouny, M. and , Myron Strongin, Phys. Rev. B 31, 4798 (1985).Google Scholar
11. Butz, R. and Wagner, H., Surf. Sci. 87, 69 (1979).Google Scholar
12. Bruce, L. A. and Jaeger, H., Philos. Mag. A 38, 223 (1978).Google Scholar
13. Nicholas, John F., An Atlas of Models of Crystal Surfaces (Gordon and Breach, New York, 1973).Google Scholar
14. Lagally, M. G. in Methods of Experimental Physics, v. 22. Solid State Physics: Surfaces, edited by Park, R. L. and Lagally, M. G. (Academic Press, New York, 1985) p. 237.Google Scholar
15. Bauer, E. and Poppa, H., Thin Solid Films 12 167 (1972); A. Franciosi, D. J. Peterman, J. H. Weaver and V. L. Horuzzi, Phys. Rev. B25, 4981 (1982).Google Scholar
16. Ruckman, M. W., Jiang, Li-Qiang and Strongin, Myron, Phys. Rev. B (submitted).Google Scholar
17. El-Batanouny, M., Hamann, D. R., Chubb, S. R. and Davenport, J. W., Phys. Rev. B 27, 2575 (1983).Google Scholar
18. Ruckman, M. W., Murgai, V. and Strongin, Myron, Phys. Rev. B (in press).Google Scholar
19. Kumar, V. and Bennemann, K. H., Phys. Rev. B 28, 3138 (1983).CrossRefGoogle Scholar
20. El-Batanouny, M., Strongin, M. and Williams, G. P., Phys. Rev. B 27, 4580 (1983).Google Scholar
21. Ashcroft, N. W. and Mermin, N. D., Solid State Physics (Holt, Rinehart and Winston, New York, 1976).Google Scholar
22. Lee, S. T., Apai, G., Mason, M. G., Benbow, R. and Hurych, Z., Phys. Rev. B 23, 505 (1981).Google Scholar
23..Kolaczkiewicz, J. and Bauer, E., Surf. Sci. 160, (1985).Google Scholar
24. Sidorski, Z., Appl. Phys. A 33, 213 (1984).CrossRefGoogle Scholar
25. Harrison, W. A., Electronic Structure and the Properties of Solids, (W. H. Freeman and Co., San Francisco, 1980).Google Scholar
26. Trenary, M., Tan, S. L., Simonson, R. J. and McFeely, F. R., Surf. Sci. 124, 555 (1983).Google Scholar
27. Plummer, E. W., Salaneck, W. R. and Miller, J. S., Phys. Rev. B 18, 1673 (1978); H.-J. Freund and E. W. Plummer, Phys. Rev. B23, 4859 (1981).Google Scholar
28. Schbnhamer, K. and Cunnarson, O., Z. Physik B 30, 297 (1978).Google Scholar
29. Ruckman, M. W., Pan, Xiaohe and Strongin, Myron, J. Vac. Sci. Technol. (in press).Google Scholar