Universal Expression for Blocking Cone Size in Low Energy Ion Scattering Based on MD Simulations

Abstract

Calculations of blocking cone sizes for low energy ion scattering have been performed. By fitting calculated points in the space of the parameters of the interacting atomic species, a universal formula for calculating the blocking cone size for arbitrary energies and interacting species has been derived. The blocking cones in this low energy range are appreciably asymmetric with respect to the interatomic axis. At small interatomic distances and low projectile energies, the difference in the upper and lower halves of the blocking cone can be as large as 15%. The results of MD simulations using the Ziegler-Biersack-Littmark (ZBL) potential are in good agreement with experimental blocking cone sizes.