AN IMPROVED MOLECULAR-DYNAMICS SCHEME FOR ION-BOMBARDMENT SIMULATIONS

We have developed a method that reduces the CPU time required in molec ular dynamics simulations of ion bombardment processes. This method is based on the selective integration of the particles of the system dep ending on their energy. Low energy particles are integrated less frequ ently than the high energy ones. In order to test our scheme we have c arried out simulations of Ar+ bombardment of Si(100) at 300 K. Using t his method gain factors up to 5.9 in computation speed have been achie ved. The accuracy of the results was satisfactory in terms of total en ergy conservation and of the description of the individual trajectorie s of the atoms along the simulation.