Муаровые узоры в графене на подложке Pt(111): компьютерное моделирование

Deformation study for monolayer graphene film on Pt substrate is performed by computer simulation. The surface potential simulates the substrate. Carbon atoms in graphene interact with each other and with the potential of the substrate. The minimum of potential energy determines the position of carbon atoms. Transverse strains of graphene are energetically advantageous due to the strong bond between carbon atoms. Longitudinal deformations in graphene are small. The model uses the Lennard– Jones potential to calculate the substrate potential. The potential parameters are calculated from the equilibrium state of the unperturbed system and experimental data. The surface potential is calculated for one unit cell and translated by parallel transfer to the entire substrate. The interaction between carbon atoms is also described by the Lennard–Jones potential. Moire patterns in graphene have a honeycomb superstructure. The model calculates the dependence of the period for the moire pattern on the angle between the main directions of the crystal lattice on the substrate and graphene. The period of the moire superlattice decreases when the film is rotated according to a nonlinear law. Calculations show a large distance between the substrate and the graphene film. The simulation results are in good agreement with the experimental data