Insertion of 1,10-decanedithiol in decanethiolate self-assembled monolayers onAu{111}

Abstract

Decanethiolate self-assembled monolayers (SAMs) on Au{111} have been used as hostmatrices for the molecular insertion of 1,10-decanedithiol from dilute ethanolic solutionsinto film defect sites. The inserted 1,10-decanedithiolate molecules were observed asprotrusions in topographic scanning tunnelling microscopy (STM) images. With thismethod, each 1,10-decanedithiolate molecule adopts an orientation with a singleAusurface–thiolate bond with the distal thiol termini protruding from the SAM. Subsequent topographicSTM images captured the molecular migration of inserted 1,10-decanedithiolate molecules,and this event is attributed either to molecular movement up or down a gold step edge orreconstruction of a gold vacancy island.