Collapse phase diagram of carbon nanotubes with arbitrary number of walls. Collapse modes and macroscopic analog

Carbon nanotubes tend to collapse when their diameters exceed a certain threshold, or sufficiently large external pressure is applied on walls. The radial stability of tubes has been studied in each these cases, however general theory able predict still lacking. Here, we propose simple model predicting limits as function the tube diameter, number walls and pressure. supported by atomistic simulations, experiments, used plot phase diagrams. We have identified most stable carbon nanotube, which can support maximum ?18 GPa before collapsing. latter was multiwall with an internal diameter ?12 nm ?30 This lowered depending then identify domain mechanical be treated equivalent macroscopic tubes, known described canonical Lévy-Carrier law. multiscale behavior shown good agreement experiments O-rings, proposed parallel this domain.