Simulation of core excitation during cluster impacts

Core excitation in Al atoms following the impact of pure Al clusters and composite Al--Au clusters on Au surfaces has been investigated by molecular-dynamics simulation. Core excitation was found to be most probable during the early, compressional phase of cluster impacts. The simulations predict that a significant fraction of the core-excited Al cluster atoms will decay by atomic-like Auger emission following ejection from the surface, providing a useful diagnostic tool to investigate collisions of cluster ions with surfaces.