Applied Surface Science, Vol.254, No.21, 7000-7007, 2008
Population dynamics of the ions SVI, ClVII and ArVIII interacting with solid surfaces
We used the recently developed time-symmetrized, two-state vector model to investigate the intermediate stages of the electron capture into the Rydberg states (n(A) >> 1; l(A) = 0 - 3, m(A) = 0) of multiply charged ions SVI, ClVII and ArVIII, with polarized core charges Z = 6, 7 and 8, respectively, escaping solid surfaces at low velocities. Within the framework of the model, the two wave functions are used to describe the system at intermediate stages; the corresponding probabilities and rates are based on the calculation of the mixed flux. The simple analytical formulae derived for the neutralization rates enable us to analyze the localization of the process and to calculate the neutralization distances. In the pointlike core approximation, the rates are comparable with the available coupled-angular-mode results. The neutralization distances follow the classical predictions for all considered Rydberg states with exception of the states with critical quantum numbers n(A) = n(c), mainly populated via tunneling mechanism; the corresponding values are larger than it is predicted by the classical overbarrier model. Inclusion of core polarization significantly reduces the neutralization distances. (C) 2008 Elsevier B. V. All rights reserved.