NO Vibrational Energy Transfer on a Metal Surface: Still a Challenge to First-Principles Theory

Abstract

During a collision of highly vibrationally excited NO with a Au(111) surface, the molecule can lose a large fraction of its vibrational energy into electronic excitation of the metal. This process violates the Born-Oppenheimer approximation and represents a major challenge to theories of molecule-surface interaction. Two ab initio approaches to this problem, one using independent electron surface hopping (IESH) and the other electronic friction, previously reported good agreement with the limited available data on multiquantum vibrational relaxation; however, at that time only experiments for NO(v(i) = 15) at an incidence translational energy of E-i = 0.05 eV were available. In this work, we report a comparison of recently reported experiments characterizing the multiquantum vibrational relaxation of NO on Au(111) for a wider range of incidence translational and vibrational energies to IESH and molecular dynamics with electronic friction (MDEF) calculations for these conditions. Both theories fail to explain the large amount of vibrational energy transferred from NO to the solid.