Bridge-bonded methylthiolate on Au(111) observed with the scanning tunneling microscope.

ABSTRACT

We report the discovery of bridge-bonded methylthiolate, SCH3, along the step edges of the Au(111) surface. Real-space imaging with a scanning tunnelling microscope reveals the presence of bridge-bonded SCH3 along both the [11[combining macron]0] and the [112[combining macron]] oriented step edges. The nearest neighbour distances of SCH3 along these steps are 2a and , respectively. The Au(111) terrace is covered with the usual CH3SAuSCH3 staples. The bridge-bonded alkanethiolate is expected to play a rather significant role in the formation of thiol-passivated Au nanoclusters because of the high fraction of atoms in similar low-coordination sites.