I would like to study the collision of argon atoms with a silicon substrate to form ripples. I carry out Molecular Dynamics (MD) simulations using LAMMPS. Please suggest a suitable potential. I tried with individual SW, tersoff potentials and their hybrid potential, but 500 eV argon atoms are going more than 25 lattice constants distance inside silicon, which is not expected. Are there any alternative methods other than MD simulations to observe the ripple formation on silicon?