Self-assembled molecular corrals on a semiconductor surface

Nano-corrals formed by organic molecules were observed in STM experiments.

The 1-chlorododecane, physisorbed on Si(111)-(7 x 7) self-assemble to form dimers

which corral silicon adatoms.

Corral size is governed by the haloalkane chain-length.

Spectroscopic and theoretical evidence shows that the haloalkane dimer induces

electron transfer to the corralled adatom, shifting its energy levels by 1 eV.

Isolation of a labile pre-cursor points to a model for corral

formation which combines mobility with immobility;

monomers diffusing in a mobile vertical state meet and convert to the immobile

horizontal dimers constituting the corrals.

This work was published in: "Maskless nanopatterning and formation of nanocorrals and switches, for haloalkanes at Si(111)-7 × 7", S. Dobrin, K.R. Harikumar, T B Lim, L Leung, I.R. McNab, J.C. Polanyi, P.A. Sloan, Z. Waqar, J (S Y) Yang, S Ayissi, and W.A. Hofer, Nanotechnology, 18 (2007) 044012

 "Molecular dynamics of haloalkane corral formation and surface halogenation at Si(111)-7×7", S. Dobrin, K. R. Harikumar, R.V. Jones, I. R.  McNab, J. C. Polanyi, Z. Waqar, and J. Yang, J. Chem. Phys., 125, 133407 (2006)

 "STM Study of the Conformation and Reaction of long-Chain Haloalkanes at Si(111)-7x7, S. Dobrin, K.R. Harikumar, J.C. Polanyi, J. Phys. Chem. B. 110 (2006) 8010

 "Self-assembled molecular corrals on a semiconductor surface", S. Dobrin, K.R. Harikumar, R.V. Jones, N. Li, I.R. McNab, J.C. Polanyi, P.A. Sloan, Z. Waqar, J.(S.Y.) Yang, S. Ayissi, W.A. Hofer, Surface Science, 600 (2006) L43. This paper became a subject of a perspective paper by Professor G. Dujardin, Universite´ Paris-Sud, and also has been cited by Chem. &. Eng. News on February 27, 2006