Stopping of copper clusters in copper

The molecular-dynamics simulation technique is used to study the penetration of 0.1 and 1 keV/at. copper clusters through a thin polycrystalline copper foil. Just as in the case M1 ≥ M2 (M1=cluster atom mass; M2=target atom mass) studied earlier, the stopping power per cluster atom proves to be much lower compared with the case of bombardment with single atoms. The results obtained are interpreted by analyzing the stopping powers of the front and rear cluster atoms and by examining some elementary collision processes under cluster and atom bombardment. (orig.)