A new empirical potential for layered graphitic materials is reported. Interatomic interactions within a single graphene sheet are modeled using a Stillinger-Weber potential. Interatomic interactions between atoms in different sheets of graphene in the nanoplatelet are modeled using a Lennard-Jones interaction potential. The potential is validated by comparing molecular dynamics simulations of tensile deformation with the reported elastic constants for graphite. The graphite is found to fracture into graphene nanoplatelets when subjected to ∼15% tensile strain normal to the basal surface of the graphene stack, with an ultimate stress of 2.0 GPa and toughness of 0.33 GPa. This force field is useful to model molecular interactions in an important class of composite systems comprising 2D materials like graphene and multi-layer graphene nanoplatelets.

中文翻译：

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石墨烯纳米片分子模拟的经验潜力

报道了层状石墨材料的新的经验潜力。使用Stillinger-Weber势对单个石墨烯片内的原子间相互作用进行建模。使用Lennard-Jones相互作用势对纳米片中不同石墨烯薄片中原子之间的原子间相互作用进行建模。通过将拉伸变形的分子动力学模拟与所报道的石墨弹性常数进行比较，可以验证这种潜力。发现石墨在垂直于石墨烯叠层基础表面承受约15％的拉伸应变时会破裂成石墨烯纳米片，其极限应力为2.0 GPa，韧性为0.33 GPa。该力场对于在重要类别的复合系统中建模分子相互作用很有用，该复合系统包含2D材料（例如石墨烯和多层石墨烯纳米片）。