title: Thermomechanical properties of graphene: valence force field model approach.
abstract: Using the valence force field model of Perebeinos and Tersoff (2009 Phys. Rev. B 79 241409(R)), different energy modes of suspended graphene subjected to tensile or compressive strain are studied. By carrying out Monte Carlo simulations it is found that: (i) only for small strains (|ε| </≈ 0.02) is the total energy symmetrical in the strain, while it behaves completely differently beyond this threshold; (ii) the important energy contributions in stretching experiments are stretching, angle bending, an out-of-plane term, and a term that provides repulsion against π-π misalignment; (iii) in compressing experiments the two latter terms increase rapidly, and beyond the buckling transition stretching and bending energies are found to be constant; (iv) from stretching-compressing simulations we calculated the Young's modulus at room temperature 350 ± 3.15 N m(-1 ), which is in good agreement with experimental results (340 ± 50 N m(-1 )) and with ab initio results (322-353) N m(-1 ); (v) molar heat capacity is estimated to be 24.64 J mol(-1 ) K(-1 ) which is comparable with the Dulong-Petit value, i.e. 24.94 J mol(-1) K(-1), and is almost independent of the strain; (vi) nonlinear scaling properties are obtained from height-height correlations at finite temperature; (vii) the used valence force field model results in a temperature independent bending modulus for graphene, and (viii) the Grüneisen parameter is estimated to be 0.64.
authors.affiliation: Department of Physics, Eastern Mediterranean University, G Magusa, North Cyprus, Mersin 10, Turkey.
authors.forename: A
authors.initials: A
authors.lastname: Lajevardipour
authors.forename: M
authors.initials: M
authors.lastname: Neek-Amal
authors.forename: F M
authors.initials: FM
authors.lastname: Peeters
mesh_terms: D003198:Computer Simulation; D055119:Elastic Modulus; D004548:Elasticity; D006108:Graphite / Q000737:chemistry*; D015233:Models, Statistical; D009010:Monte Carlo Method; D010825:Physics / Q000379:methods*; D015203:Reproducibility of Results; D013696:Temperature; D013816:Thermodynamics
chemical_list: D006108:Graphite