Neutralization of hyperthermal multiply charged ions at surfaces:: Comparison between the extended dynamical overbarrier model and experiment

Within a semiclassical model, we investigate the dynamic neutralization and relaxation of slow (E-kin <100 eV) multiply charged ions which are reflected on metal surfaces. Special emphasis is devoted to nearsurface interaction mechanisms. Our model includes a Monte Carlo sampling over projectile parameters and detailed ionic structure calculations of projectile energy levels. In a full trajectory simulation, our results simultaneously comply with measured trends in projectile kinetic energy gains and final charge-state distributions of the reflected ions as well as total electron yields and spectra. Recently discovered characteristic features in the electron spectra can be uniquely assigned to distinct above-surface regions of the projectile trajectory. [S1050-2947(99)03009-7].