Collective Reactivity of Molecular Chains Self-Assembled on a Surface
Peter Maksymovych,1,2
Dan C. Sorescu,3
Kenneth D. Jordan,1
John T. Yates, Jr.1,4*
Self-assembly of molecules on surfaces is a route toward not
only creating structures, but also engineering chemical reactivity
afforded by the intermolecular interactions. Dimethyldisulfide
(CH
3SSCH
3) molecules self-assemble into linear chains on single-crystal
gold surfaces. Injecting low-energy electrons into individual
molecules in the self-assembled structures with the tip of a
scanning tunneling microscope led to a propagating chemical
reaction along the molecular chain as sulfur–sulfur bonds
were broken and then reformed to produce new CH
3SSCH
3 molecules.
Theoretical and experimental evidence supports a mechanism involving
electron attachment followed by dissociation of a CH
3SSCH
3 molecule
and initiation of a chain reaction by one or both of the resulting
CH
3S intermediates.
2 Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.
3 U.S. Department of Energy, National Energy Technology Laboratory, Pittsburgh, PA 15236, USA.
4 Department of Chemistry, University of Virginia, Charlottesville, VA 22904, USA.
* To whom correspondence should be addressed. E-mail: johnt{at}virginia.edu
