Photodesorption of neutrals from metal surfaces: a wave packet study Original Research Article

By solving the time-dependent Schrödinger equation for representative wave packets, the desorption dynamics of neutrals from metal surfaces following photoexcitation is studied. Computational parameters are chosen to resemble NO/Pt(111). Three different one-dimensional models of increasing complexity are employed to elucidate (a) basic dynamical features, (b) the role of dissipative boundary conditions and (c) non-phenomenological quenching rates. Among the computed quantities are desorption probabilities, density and flux time-of-flight spectra, kinetic energies of the desorbing particles, and “snapshots” of the wave packets in configuration and momentum space. Besides others, effects of the initial vibrational excitation of the molecule-surface bond by temperature or by IR laser pulses, and of coordinate-dependent resonance lifetimes are discussed.