Molecular Dynamics Simulation to Study the Effect of Empirical Potential Functions on Modeling of Diamond-Like Carbon

Abstract

Molecular dynamics (MD) simulations is an effective method to investigate the mechanical and tribological properties of amorphous carbon since the coordinates of all atoms can be calculated as a function of time. Several empirical potentials can be used to model the interatomic interactions of carbon atoms, including the Tersoff potential, the Reactive Bond Order (REBO) potential and its revised versions, and the Reactive Force Field (ReaxFF) potential. The choice of empirical potential is one of the fundamental and important assumptions in the MD approach since it can affect the properties of amorphous carbon during the MD simulations. In this study, liquid quenching method is used to model amorphous carbon for computational efficiency. We will study the influence of the three types of potentials, specifically the Tersoff potential, the 2nd REBO potential and the ReaxFF potential on DLC parameters. These parameters include the sp3 content as a function of density, the arrangement of the amorphous carbon atoms, hybridization and the radial distribution functions G(r).