Uniform radial expansion/contraction of carbon nanotubes
نویسندگان
چکیده
Carbon nanotubes have very high potential for applications in nanoelectromechanical devices, nano-optomechanical systems and nanocomposites. However, their full exploitation depends upon knowledge of their mechanical, electrical and thermal properties. Several analytical, experimental, molecular mechanics (MM) and molecular dynamics simulations have been performed to study their deformations under axial loads. Here a novel MM simulation technique has been developed to study uniform radial expansion/contraction of a single wall carbon nanotube (SWCNT). Radial deformations of a SWCNT are achieved by considering a double wall carbon nanotube (DWCNT) with the SWCNT as one of its walls and moving radially through the same distance all atoms of the other wall of the DWCNT thereby causing a pseudo-pressure through changes in the cumulative van der Waals forces which deform the desired wall. These results are used to find throughthe-thickness elastic moduli (Young’s modulus in the radial direction, Er , and Poisson’s ratio, νrθ ) of the SWCNT. (Some figures in this article are in colour only in the electronic version)
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