Pyridine Ion Damage of Methane Thiolate Covered Ag(111) during Surface-Induced Dissociation

Abstract

The pyridine ion beam damage and surface-induced dissociation (SID) spectra of the simplest self-assembled monolayer, methanethiolate adsorbed on Ag(111), was examined using tandem mass spectrometry combined with infrared reflection absorption spectroscopy. Pyridine ions (C 5 H 5 N + and C 5 D 5 N + ) were found to significantly damage the methanethiolate at incident energies of 32 and 64 eV: up to 50% of the adsorbate was damaged by the ion beam over 60 min of exposure at 64 eV. Despite this dramatic ion beam modification of the self-assembled monolayer, little effect was seen in the SID spectra. The only major effect of ion exposure on the SID spectra was observed for surface temperatures of 130 K where an enhancement of all scattered ion signals appeared over time