n-alkyl thiol head-group interactions with the Au(111) surface - art. no. 081405

State-of-the-art first-principles calculations based on density-functional theory were performed on CH3(CH2)(n-1)S-Au(1 1 1) systems. We show that the adsorption site of methylthiolate at a range of coverages on the Au(1 1 1) surface is the fee site, not the hcp site as has been recently reported. F urther, we report that increasing alkane chain length enhances the fee site preference. Study of the electronic structure of the system underscores th e importance of sulfur 3d orbitals to thiol chemisorption.