Skip to main content Accessibility help

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

  • M. W. Ruckman (a1), Myron Strongin (a1) and Xiaohe Pan (a1)


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.



Hide All
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).
2. Houston, J. E., Peden, C. H. F., Blair, D. S. and Goodman, D. W., Surf. Sci. 167, 427 (1986).
3. Bauer, E. and Van der Merwe, J. H., Phys. Rev. B 33, 3657 (1986).
4. Falicov, L. M. and Somorjai, G. A., Proc. Natl. Acad. Sci. (USA), 82, 2207 (1985).
5. Pauling, L., The Nature of the Chemical Bond, 3rd ed. (Cornell University Press, Ithaca, 1960).
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.
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).
8. Sagurton, M., Strongin, M., Jona, F. and Colbert, J., Phys. Rev. B 28, 4075 (1983).
9. Pan, Xiaohe, Ruckman, M. W. and Strongin, Myron, Phys. Rev. B (submitted).
10. El-Batanouny, M. and , Myron Strongin, Phys. Rev. B 31, 4798 (1985).
11. Butz, R. and Wagner, H., Surf. Sci. 87, 69 (1979).
12. Bruce, L. A. and Jaeger, H., Philos. Mag. A 38, 223 (1978).
13. Nicholas, John F., An Atlas of Models of Crystal Surfaces (Gordon and Breach, New York, 1973).
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.
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).
16. Ruckman, M. W., Jiang, Li-Qiang and Strongin, Myron, Phys. Rev. B (submitted).
17. El-Batanouny, M., Hamann, D. R., Chubb, S. R. and Davenport, J. W., Phys. Rev. B 27, 2575 (1983).
18. Ruckman, M. W., Murgai, V. and Strongin, Myron, Phys. Rev. B (in press).
19. Kumar, V. and Bennemann, K. H., Phys. Rev. B 28, 3138 (1983).
20. El-Batanouny, M., Strongin, M. and Williams, G. P., Phys. Rev. B 27, 4580 (1983).
21. Ashcroft, N. W. and Mermin, N. D., Solid State Physics (Holt, Rinehart and Winston, New York, 1976).
22. Lee, S. T., Apai, G., Mason, M. G., Benbow, R. and Hurych, Z., Phys. Rev. B 23, 505 (1981).
23..Kolaczkiewicz, J. and Bauer, E., Surf. Sci. 160, (1985).
24. Sidorski, Z., Appl. Phys. A 33, 213 (1984).
25. Harrison, W. A., Electronic Structure and the Properties of Solids, (W. H. Freeman and Co., San Francisco, 1980).
26. Trenary, M., Tan, S. L., Simonson, R. J. and McFeely, F. R., Surf. Sci. 124, 555 (1983).
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).
28. Schbnhamer, K. and Cunnarson, O., Z. Physik B 30, 297 (1978).
29. Ruckman, M. W., Pan, Xiaohe and Strongin, Myron, J. Vac. Sci. Technol. (in press).

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

  • M. W. Ruckman (a1), Myron Strongin (a1) and Xiaohe Pan (a1)


Full text views

Total number of HTML views: 0
Total number of PDF views: 0 *
Loading metrics...

Abstract views

Total abstract views: 0 *
Loading metrics...

* Views captured on Cambridge Core between <date>. This data will be updated every 24 hours.

Usage data cannot currently be displayed