Fragmentation and energy loss in grazing scattering of copper clusters Cunfrom a single-crystal Al(111) surface

Abstract

By performing a molecular dynamics simulation, fragmentation and energy losses of neutral copper clusters Cu${}_{n}$ in grazing incidence on a single-crystal Al(111) surface under various azimuthal angles were studied. The interactions among copper atoms were modeled by tight-binding potential, and the position of each copper atom at each time step was calculated by integrating the Newton equations of motion. The percentage of unfragmented clusters as a function of incident energies, incident angles, and cluster sizes was found to be almost independent of the influence of surface structure. The regular-sized clusters without icosahedral structure appear to be less stable. The energy spectra of reflected particles for 30-keV copper clusters Cu${}_{147}$ grazing scattering were measured under three incident angles, and some additional peaks appearing on the left side of the first peak were observed for large grazing angles of incidence.