Single-wall carbon nanotube mechanical behavior using the modified embedded atom method with bond order (MEAM-BO)

We report the capability of the modified embedded atom method with bond order (MEAM-BO) potential to capture single-wall carbon nanotube (SWCNT) mechanical properties accurately by calculating the wavenumber of the radial breathing mode (RBM), elastic properties, and folding energy (ΔE), which are all associated with bond curvature. We find that the existing MEAM-BO potential gives results that correlate well with experimental and density functional theory (DFT) results with the exception of the folding energy. The MEAM-BO potential parameters are updated to produce a MEAM-BO∗ potential for the SWCNT system. Interestingly, including the SWCNT data base, improved the previous fit of the C-H binary system. Previous studies in the literature concluded that the CNTs diameter, d, was inversely proportional to the RBM wavenumber and folding energy. When comparing MEAM-BO∗, MEAM-BO, REBO, and ReaxFF with DFT results, we found that MEAM-BO∗ gave the closest results to DFT for the RBM wavenumbers, folding energy, and SWCNT Young's modulus, especially for small diameter SWCNTs. We conclude that MEAM-BO∗ captures SWCNT curvature effects and unsaturated hydrocarbons bond behavior.