Organic probe molecule adsorption on extended Au(111) surface: a theoretical DFT study

The cluster approach has been applied to mimic the interactions of probe trans -1,2-bis-(4-pyridyl) ethylene on a gold surface with the aim of discriminating the clean Au(111) surface from that containing pre-adsorbed Au ad-atoms. Our DFT calculations at the combined B3LYP/(6-31G*+Lanl2dz) level indicate that, by changing the adsorption condition, one may clearly predict the status of the gold surface which may or may not contain some artificial pre-adsorbed and highly dispersed gold ad-atoms. This conclusion is based on estimations of characteristic IR and Raman peaks assigned precisely to the distinct active sites on the Au(111) surface.