An appalication of the classical trajectory monte carlo method to the study of collisions between highly charged ions and surfaces

摘要

We have developed a classical trajectory Monte Carlo code for use in the study of collisions between highly charged ions and systems with multiple targets, such as surfaces. We have simulated a collision between the bare ions C~(6+), Kr~(36+), Ne~(10+), Ar~(18+), and Xe~(54+), and a configuration of approximately 400 individual atoms. The projectile has an initial energy of 0.25 keV/u with the velocity perpendicular to the surface. TSo simulate a simplified surface, the target atoms arre held in a simple cubic lattice arrangement by the use of Morse potentials between target nuclei. Each target nucleus has one electron with a binding energy of 12 eV initially localized about it. INitial conditions of the electrons are restricted to represent the 20 electrons of LiF anions. The forces between all particles are calculated at each step in the simulation and the trajectory of every particle is followed. Results for the critical radius of capture, and the principal numbers are show. Details of the capture of the first three electrons by Ar~(18+) as it approaches the surface are given.