Abstract
AbstractSelf-assembled monolayers （SAMs） of n-hexadecanoic acid (1), p-terphenylcarboxylic acid (2), were prepared onto silver surface by adsorption from a solution of respective compound, all through the carboxylate/silver （CO2－/Ag） interaction. A brief exposure of the monolayer to H2S vapor leads to immediate protonation of the carboxylate head groups and reorganization of the resulting free acid molecules in the monolayer into clusters of H-bonded dimers of the acid. Mixed monolayer prepared from n-hexadecanoic acid (1) and p-terphenylcarboxylic acid (2) appears to form domains of respective component on silver surface. H2S-exposure of the mixed-monolayer also leads to a reorganization of the molecules in the monolayer. For mixed monolayer, the atomic force microscopy suggests that H2S-exposure leads to aggregates of respective compounds.The effect of a self-assembled monolayer on a substrate surface on the packing/orientation of vacuum-deposited p-terphenyl film was also investigated. The nearly perpendicular orientation of the terphenyl group in the SAM of p-terphenylcarboxylic acid caused perpendicular alignment of the p-terphenyl molecules in vacuum-deposited film, whereas H2S-treated SAM surface caused parallel alignment of the p-terphenyl molecules in the deposited film.