Influence of a Xenon interlayer on dissociative electron attachment to deuterated methane on a platinum substrate
Abstract
We investigate the impact of intercalating a xenon layer between a thin condensed CD4 film of two monolayers (ML) and a platinum surface on the dissociative electron attachment (DEA). The observed desorption results are compared with density functional theory (DFT) calculations, which reveal the binding energies of various anionic and neutral species as a function of the xenon film thickness on the Pt (111) substrate. The theoretical results suggest that 6 ML of xenon are sufficient to diminish the surface effect, enabling physisorbed anionic fragments to desorb from the CD4 film. In contrast, 20 ML (approximately 10 nm) are experimentally necessary to achieve saturation in the desorption of D-. In addition, the presence of xenon layers enables the coupling of resonance states with Xe excited states, thereby inhibiting the electrons from returning to the metal. Aside from reducing surface interactions, the xenon interlayer significantly enhances DEA to CD4.