Metal overlayers on organic functional groups of self-organized molecular assemblies. II. X-ray photoelectron spectroscopy of interactions of Cu/CN on 12-mercaptododecanenitrile

The interaction of evaporated copper overlayers, from 0.03 to 0.4 nm thick, with specific terminal functional groups of an organized molecular assembly (OMA) of HS(CH2)11CN formed on gold has been studied by x-ray photoelectron spectroscopy. For average copper coverages above 0.1 nm, the peak intensities show fair agreement with a model that assumes an increasing fraction of each increment of the deposited copper penetrates the OMA and resides at the OMA/Au interface. For lower coverages, a weak Cu(CN) interaction is indicated by shifts of the N 1s level and the C 1s high binding energy (HBE) shoulder to lower binding of as well as by the presence of a Cu 2p HBE shoulder.