Molecular Dynamics Simulation of the Diffusion of a Copper Atom on Graphene

The results of studying the effect of geometric and thermodynamic parameters of thermal evaporation and copper deposition on graphene lying on the Cu(111) surface on the adsorption of copper atoms, as well as their surface diffusion, are presented. The simulation is carried out by classical molecular dynamics using chains of Nose–Hoover thermostats. Interatomic interactions are determined by the Tersoff–Brenner, Rosato–Guillope–Legrand, and modified Morse potentials. A simple criterion for the thermalization of adatoms on graphene lying on a Cu(111) surface is formulated and tested. The average length and the mean free path time of the copper atom before and after thermalization at low (7 K) and room temperatures are studied for two evaporation temperatures. The probability of adsorption of the copper atom is found. The distributions along the directions of motion of adatoms during equilibrium diffusion are constructed. The distributions of the free path length and time are shown to have an exponential form. The influence of the Cu(111) substrate on the diffusion of the Cu atom on graphene is studied. The results obtained can be used to simulate the growth of copper nanoclusters on graphene by the kinetic Monte Carlo method.