Molecular dynamics simulations were used for modeling the thermal and the elastic properties of fully fluorinated graphene membranes ? fluorographene (FG). Simulations were carried out for three basic crystal conformations: chair, bed and washboard structures, as well as for FG membranes with random structural defects. The coefficients of temperature extension and the equilibrium geometric parameters (bond lengths and angles), were obtained for the temperature range from 1 to 300 K. Computer simulation of the extension and compression of the membrane made it possible to calculate the longitudinal stiffness, Poisson's ratios and the bending stiffness at 1 and 300 K. The obtained values of the Young modules for 2D crystal structures accords well with the corresponding quantum-mechanical calculations. At the same time, the Young modules for the membranes with defects in crystalline structure were approximately 2.5 times less, which is consistent with the known experimental data. Probably, this is circumstantial evidence of the fact that the FG membranes obtained in the experiments have a big deficiency.
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