title: Hybridization of phenylthiolate- and methylthiolate-adatom species at low coverage on the Au(111) surface.
abstract: Using scanning tunneling microscopy we observed reaction products of two chemisorbed thiolate species, methylthiolate and phenylthiolate, on the Au(111) surface. Despite the apparent stability, organometallic complexes of methyl- and phenylthiolate with the gold-adatom (RS-Au-SR, with R as the hydrocarbon group) undergo a stoichiometric exchange reaction, forming hybridized CH3S-Au-SPh complexes. Complementary density functional theory calculations suggest that the reaction is most likely mediated by a monothiolate RS-Au complex bonded to the gold surface, which forms a trithiolate RS-Au-(SR)-Au-SR complex as a key intermediate. This work therefore reveals the novel chemical reactivity of the low-coverage "striped" phase of alkanethiols on gold and strongly points to the involvement of monoadatom thiolate intermediates in this reaction. By extension, such intermediates may be involved in the self-assembly process itself, shedding new light on this long-standing problem.
authors.affiliation: Center for Nanophase Materials Sciences, Oak Ridge National Laboratory , Oak Ridge, Tennessee 37831, United States.
authors.forename: Petro
authors.initials: P
authors.lastname: Maksymovych
authors.forename: Dan C
authors.initials: DC
authors.lastname: Sorescu
authors.forename: Oleksandr
authors.initials: O
authors.lastname: Voznyy
authors.forename: John T
authors.initials: JT
authors.lastname: Yates