title: Self-assembly of a pyridine-terminated thiol monolayer on Au(111).
abstract: Self-assembled monolayers (SAMs) of 3-(4-pyridine-4-yl-phenyl)-propane-1-thiol (PyP3) on Au(111)/mica have been studied by scanning tunneling microscopy (STM), polarization-modulated infrared reflection absorption spectroscopy (PM-IRRAS), high-resolution X-ray photoemission spectroscopy (HRXPS), and near-edge X-ray absorption fine structure (NEXAFS) spectroscopy. The quality of the SAM is found to be strongly dependent on the solvent. Substantial gold corrosion is observed if pure ethanol is used. In contrast, highly ordered and densely packed SAMs are formed from acetonitrile or a KOH/ethanol mixture. The structure is described by a 2 radical3 x radical3 unit cell with the aromatic moiety oriented nearly perpendicular to the surface. The PyP3 films form with the pyridine moiety deprotonated. Variation of pH allows reversible protonation without measurable damage of the SAM.
authors.affiliation: EaStChem School of Chemistry, University of St. Andrews, North Haugh, St. Andrews KY16 9ST, UK. cjcs@st-andrews.ac.uk
authors.forename: Christophe
authors.initials: C
authors.lastname: Silien
authors.forename: Manfred
authors.initials: M
authors.lastname: Buck
authors.forename: Gudrun
authors.initials: G
authors.lastname: Goretzki
authors.forename: Dorothée
authors.initials: D
authors.lastname: Lahaye
authors.forename: Neil R
authors.initials: NR
authors.lastname: Champness
authors.forename: Tobias
authors.initials: T
authors.lastname: Weidner
authors.forename: Michael
authors.initials: M
authors.lastname: Zharnikov
mesh_terms: D000538:Aluminum Silicates / Q000737:chemistry; D006046:Gold / Q000737:chemistry*; D008567:Membranes, Artificial; D016252:Microscopy, Scanning Tunneling; D015394:Molecular Structure; D010316:Particle Size; D011725:Pyridines / Q000138:chemical synthesis / Q000737:chemistry*; D013057:Spectrum Analysis; D013438:Sulfhydryl Compounds / Q000138:chemical synthesis / Q000737:chemistry*; D013499:Surface Properties; D014965:X-Rays
chemical_list: C535262:3-(4-pyridine-4-yl-phenyl)-propane-1-thiol; D000538:Aluminum Silicates; D008567:Membranes, Artificial; D011725:Pyridines; D013438:Sulfhydryl Compounds; D006046:Gold; C011934:mica