AVS 54th International Symposium | |
Surface Science | Thursday Sessions |
Session SS2+EM+TF-ThA |
Session: | Organics and Carbon Films on Silicon |
Presenter: | P.M. Ryan, CRANN, Trinity College Dublin, Ireland |
Authors: | P.M. Ryan, CRANN, Trinity College Dublin, Ireland L.C. Teague, National Institute of Standards and Technology J.J. Boland, CRANN, Trinity College Dublin, Ireland |
Correspondent: | Click to Email |
We consider the reactions of 1,3-cyclohexadiene (1,3-CHD)1,2 and Naphthalene on Si(100) and examine possible origins for the surface adsorption selectivity evident from STM measurements. The major adsorption products for both molecules are identified by STM. DFT calculations are carried out in order to examine the energetics of the major products and their associated structural analogs. The calculations reveal that the theoretical product distributions based on thermodynamics alone, for both systems, differ significantly from the experimental ones. We explain, using an extended frontier orbital analysis, that secondary orbital interactions which can discriminate between certain concerted reactions and are unavailable at the Γ point due to symmetry considerations become feasible at other κ points in the surface Brillouin zone. We propose that these interactions play a role in the kinetics of the adsorption process and may account for the observed reaction selectivity.
1 Teague, L.C. and J.J. Boland, STM Study of Multiple Bonding Configurations and Mechanism of 1,3-Cyclohexadiene Attachment on Si(100). Journal of Physical Chemistry B, 2003. 107(16): p. 3820-3823.
2 Teague, L.C., D. Chen, and J.J. Boland, DFT Investigation of Product Distribution Following Reaction of 1,3-Cyclohexadiene on the Si(100)Surface. Journal of Physical Chemistry B, 2004. 108(23): p. 7827-7830.