Interaction of aromatic molecules with silica film supported on Ru(0001) using UHV Experiment and DFT*

Organic molecules show promising electronic properties for future devices. The performance of organic devices depends strongly on the atomic and electronic properties at the interface with metallic substrate. In order to understand this interface, we chose two simple probe organic molecules (benzene and pyridine) and studied their interaction with Ru(0001) surface, using Density Functional Theory (DFT) with and without decoupling inert silica layer in between. Diffusion characteristics of molecules on and under the thin-film was also analyzed using Nudged Elastic Band (NEB). In order to validate computational predictions, interaction of molecules with silica film was studied using Temperature Programmed Desorption (TPD) and X-ray Photoelectron Spectroscopy (XPS) measurements. Our results from both sources, indicate that the molecules not only physisorb on silica layer rather they also seep through silica film to react with the metal. Through joint venture of theory and experiment, cross-validation of results is obtained.