Hostname: page-component-586b7cd67f-t7fkt Total loading time: 0 Render date: 2024-12-01T00:47:25.402Z Has data issue: false hasContentIssue false
  • English
  • Français

First-principles Study of Adsorption Energetics of Alkanethiols on GaAs(001)

Published online by Cambridge University Press:  01 February 2011

Oleksandr Voznyy  and
Jan J. Dubowski
Oleksandr Voznyy
Affiliation:
[email protected], University of Sherbrooke, Department of Electrical and Computer Engineering, 2500, boul. de l'Université, Sherbrooke, J1K 2R1, Canada, (819) 821-8000 # 61210
Jan J. Dubowski
Affiliation:
[email protected], Université de Sherbrooke, Department of Electrical and Computer Engineering, 2500, boul. de l'Université, Sherbrooke, J1K 2R1, Canada
Get access

Abstract

Adsorption of alkanethiols on GaAs (001) surface under low coverage conditions was studied using density functional calculations in a periodic supercell approach. The study of physisorbed precursor and transition to chemisorption revealed that hydrogen atoms stay on the surface upon S-H bond cleavage and significantly affect desorption products and energies, in agreement with available experimental data. Binding of thiols to GaAs is found to be comparable or stronger than that of thiols to noble metals surfaces. Calculated thiolate-surface binding energies are found to be higher for Ga-rich than for As-rich surfaces, and are strongly dependent on surface reconstruction, adsorption site and coverage. This dependence is explained by the violation or fulfillment of electron counting rule, rehybridization of surface atom orbitals and strain relaxation upon addition of extra electrons brought by adsorption.

Keywords

adsorptionself-assemblyIII-V
Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 950: Symposium D – Biosurfaces and Biointerfaces , 2006 , 0950-D04-44
Copyright
Copyright © Materials Research Society 2007

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1. Lunt, S. R., Ryba, G. N., Santangelo, P. G., Lewis, N. S., J. Appl. Phys. 70, 7449 (1991).Google Scholar
2. Nakagawa, O. S., Ashok, S., Sheen, C. W., Martensson, J., Allara, D. L., Jap. J. Appl. Phys. 30, 3759 (1991).Google Scholar
3. Schreiber, F., Progr. Surf. Sci. 65, 151 (2000).Google Scholar
4. Cometto, F. P., Paredes-Olivera, P., Macagno, V. A., Patrito, E. M., J. Phys. Chem. B 109, 21737 (2005).Google Scholar
5. Soler, J. M., Artacho, E., Gale, J. D., Garcia, A., Junquera, J., Ordejon, P., Sanchez-Portal, D., J. Phys. Cond. Matt. 14, 2745 (2002).Google Scholar
6. Voznyy, O., Dubowski, J. J., J. Phys. Chem. B 110, (2006).Google Scholar
7. Singh, N. K., Doran, D. C., Surf. Sci. 422, 50 (1999).Google Scholar
8. Pashley, M. D., Phys. Rev. B 40, 10481 (1989).Google Scholar