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arXiv · 1711.00249

Atomistic potential for graphene and other sp$^2$ carbon systems

Zacharias G. Fthenakis·George Kalosakas·Georgios D. Chatzidakis·Costas Galiotis·Konstantinos Papagelis·Nektarios N. Lathiotakis
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Abstract

We introduce a torsional force field for sp$^2$ carbon to augment an in-plane atomistic potential of a previous work (Kalosakas et al, J. Appl. Phys. {\bf 113}, 134307 (2013)) so that it is applicable to out-of-plane deformations of graphene and related carbon materials. The introduced force field is fit to reproduce DFT calculation data of appropriately chosen structures. The aim is to create a force field that is as simple as possible so it can be efficient for large scale atomistic simulations of various sp$^2$ carbon structures without significant loss of accuracy. We show that the complete proposed potential reproduces characteristic properties of fullerenes and carbon nanotubes. In addition, it reproduces very accurately the out-of-plane ZA and ZO modes of graphene's phonon dispersion as well as all phonons with frequencies up to 1000~cm$^{-1}$.

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Zacharias G. Fthenakis, George Kalosakas, Georgios D. Chatzidakis, Costas Galiotis, Konstantinos Papagelis, Nektarios N. Lathiotakis. 2017-11-01. Atomistic potential for graphene and other sp$^2$ carbon systems. https://doi.org/10.1039/c7cp06362h

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