Molecular Dynamics simulation of the desorption of molecules by energetic fullerene impacts on graphite and diamond surfaces

Abstract

Molecular Dynamics computer simulations have been used to investigate the energy propagation following an energetic fullerene impact on both diamond and graphite lattices. Transverse and longitudinal waves are seen to propagate across the surface particularly for the graphite. This paper investigates the possibility of desorption of large molecules – both physisorbed and chemisorbed – from the surface due to the passage of these waves. SIMS experiments using cluster ions suggest that this could be a viable technique for desorbing large intact molecules from surfaces. So far SIMS work has concentrated on the use of metal surfaces to enhance the secondary ion emission. We investigate here the use of carbon targets – in particular graphite – where the possibility of ejection of large intact molecules is potentially greater.