Transient Trapping Desorption of Molecules at Surfaces

Abstract
Scattering studies of hyperthermal O2 from Ag(111) for a backscattering geometry are reported. Three different scattering paths are observed: physisorption followed by desorption, direct-inelastic scattering, and transient trapping desorption. The latter process is attributed to transient adsorption of the molecule in an O2δ state at the surface without equilibration of the vibrational degree of freedom. The molecule desorbs with hyperthermal energy.