Abstract
For slow ions scattered from a clean and flat LiF(001) surface under a grazing angle of incidence, large fractions of negative ions have recently been observed in the reflected beam, while for neutral projectiles no negative ions are produced in the same velocity range [P. Roncin et al., Phys. Rev. Lett. 89, 043201 (2002)]. From detailed studies on projectile energy loss and charge fractions, the conclusion was drawn that the ions are formed from via a simultaneous capture of two electrons from adjacent sites at the surface. We present a theoretical description of the double-electron-capture process leading to formation from projectiles grazingly scattered from the LiF(001) surface. We use quantum chemistry calculations to determine the relevant Hamiltonian matrix and close-coupling solution of the time-dependent Schrödinger equation. The theoretical results are in good agreement with experimental observations.
- Received 31 July 2002
DOI:https://doi.org/10.1103/PhysRevB.67.115403
©2003 American Physical Society