Adsorption state of dimethyl disulfide on Au(111): Evidence for adsorption as thiolate at the bridge site

摘要

We studied the adsorption state of dimethyl disulfide and methylthiolate on the Au(1 11) surface by means of the density functional theory (DFT) within a generalized gradient approximation and experimental high-resolution electron energy loss spectroscopy (HREELS) techniques. It turns out that the methyithiolate adsorption is more stable than the dimethyl disulfide adsorption and that the most stable adsorption site for the methyithiolate is the bridge site slightly off-centered towards the fcc-hollow site with its S—C bond tilted from the surface normal by 530· HREELS results are in excellent agreement with the DFT results, providing very strong support to the depicted adsorption scenario.