Elastic buckling of single-walled carbon nanotube ropes under high pressure

A modified elastic honeycomb model is presented to study elastic buckling of single-walled carbon nanotube ropes under high pressure. Simple formula is given for the critical pressure as a function of the Young's modulus and the thickness-to-radius ratio. For single-walled carbon nanotubes of diameters around 1.3 nm, the predicted critical pressure is about 1.8 GPa, which is in excellent agreement with the known data reported in the literature. This suggests that the elastic buckling would be responsible for the pressure-induced abnormalities observed for vibration modes and electric resistivity of single-walled carbon nanotube ropes.