Molecular Dynamics Simulation of the Thermo-mechanical Properties of Monolayer Graphene Sheet

Structural, thermodynamic and mechanical properties of monolayer hexagonal graphene sheet are studied using Classical Molecular Dynamics (MD) simulation under pressure and varying temperature. We used a tersoff interatomic potential, tuned mainly for layered structures. The potential gives structurally and mechanically stable monolayer graphene sheets with an elastic modulus of 1.077 TPa. Various physical properties of graphene sheet including the thermal expansion coefficient, Radial distribution function, temperature dependence of lattice parameter, cohesive energy, elastic constants and stress-strain relation have been examined. In the present study, the negative thermal expansion coefficient (TEC) of graphene sheet in particular temperature range is observed. The thermally excited ripples are also observed in the present study. Our results compared with the existing theoretical as well as experimental results indicate the mechanical stability of graphene and it may greatly influence the material in its future applications.