The Structure of Adsorbed Methane on the MgO(100) Surface from Inelastic Neutron Scattering and First-Principles Calculations

The adsorption of molecules onto a solid surface is a phenomenon with important ramifications in areas such as catalysis, corrosion, and electronics. We have used plane-wave, psuedopotential-based density functional calculations, in conjunction with inelastic neutron scattering (INS), to evaluate the structure of methane on the MgO(100) surface. The combination of high-resolution INS and high-quality calculations has proven extremely versatile in determining the structural arrangement, despite the existence of multiple energetically favorable arrangements. The structures for adsorbed methane mono-, bi-, and higher order adlayers are discussed.