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Carbon nanoring (CNR) with heptagon–pentagon defects is formed by single-walled carbon nanotubes (SWCNTs) (5, 5) and (9, 0) and each junction is constructed by connecting a heptagonal and a pentagonal carbon-atom ring. Then cutting the ring into two pieces along the junction, one pitch of carbon nanocoil will be obtained by constraining one end and stretching the other end along the helical axis. Molecular mechanics (MM) simulations are employed to investigate the mechanical characteristics of CNRs and nanocoils with and without defects. The Young's modulus of the nanoring with defects is about 282 GPa, which is larger than that of perfect nanorings with the similar ring radii, such as (5, 5) and (9, 0). The spring stiffness of the carbon nanocoil is calculated with a maximum value of 2.08 N/m, and it is found to be nonlinear and decreases with the increase in the relative elongation.

Optical manipulation on microscale and nanoscale structures opens up new possibilities for assembly and control of microelectromechanical systems and nanoelectromechanical systems. Static optical force induces constant displacement while changing optical force stimulates vibration of a microcantilever/nanocantilever. The vibratory behavior of a single carbon nanocoil cantilever under optical actuation is investigated. A fitting formula to describe the laser-induced vibration characteristics is deduced based on a classical continuum model, by which the resonance frequency of the carbon nanocoil can be determined directly and accurately. This optically actuated vibration method could be widely used in stimulating quasi-1D micro/nanorod-like materials, and has potential applications in micro-/nano-opto-electromechanical systems.