Cooperative effects and the role of surface stress in lifting the Au{111} herringbone reconstruction by adsorbing NO2: a direct insight from STM

Add to your list(s) Download to your calendar using vCal

• Steve Driver
• Friday 31 March 2006, 09:15-10:15
• U203, Chemistry, Department of.

If you have a question about this talk, please contact Dr Ruben M Garnica.

In this talk, I shall summarize our recent STM results for low-temperature adsorption of NO2 , and coadsorption with CO, on Au{111}. The STM data reveal cooperative effects in the atomistic mechanism by which the clean-surface reconstruction is lifted. Prior to this restructuring, we see distortions of the herringbone pattern, which we can understand within a Frenkel-Kontorova framework, and which indicate the presence of locally compressive stress fields around the islands that drive mesoscopic ordering of the islands. By reference to a previous STM study by Kern and co-workers of the distribution of the Au{111} surface state across the herringbone pattern, we can account for the preference of NO2 to attack particular locations on the surface. A range of inter-related structures form when CO is coadsorbed with NO2 on Au{111} under various preparation conditions. In one of these structures, the arrangement of the molecules locally confers chirality on the surface, even though the surface and the constituent molecules are all achiral. Extended co-existing domains of both chiralities are formed. Finally, I will discuss potential implications of this work for Au-catalysed reactions and for chiral synthesis.

This talk is part of the DAK Seminars series.

This talk is included in these lists:

• DAK Group Meetings
• DAK Seminars
• U203, Chemistry, Department of

Note that ex-directory lists are not shown.