Miwa Jill A, Eves Brian J, Rosei Federico, Lopinski Gregory P
Steacie Institute for Molecular Sciences, National Research Council of Canada, Ottawa, Ontario, K1A 0R6.
J Phys Chem B. 2005 Nov 3;109(43):20055-9. doi: 10.1021/jp0537658.
Dative bonding of nitrogen-containing heterocycles offers a strategy for the controlled attachment of aromatic molecules to silicon surfaces. However, while scanning tunneling microscopy shows that pyridine on clean Si(100) initially binds via a dative bonding configuration, slow conversion to a more stable bridging state, destroying the aromaticity, is observed. To restrict adsorption to the dative bonded form, we investigated the interaction of pyridine with isolated reactive sites on partially H-terminated Si(100). While dative bonding on isolated clean dimers is observed, single dangling bonds remain unreacted. This selectivity can be accounted for by the ability of the Si-Si dimers to act as electron acceptors that stabilize the dative bonded species. This observation has important implications for the controlled positioning of single molecules on silicon via dative bonding.
