Molecular dynamics evaluation of mechanical properties of carbon nanotubes with number of Stone-Wales defects

Abstract

Molecular dynamics simulation has been carried out to study the mechanical properties of a 42.59 A long armchair (6, 6), (8, 8), (10, 10), and (12, 12) single-walled carbon nanotubes (SWCNTs) with an increase number of Stone-Wales (SW) defects, by varying their relative position and orientation. Brenner bond order potential has been employed for energy minimization. In the present work, calculations of fundamental mechanical properties of SWCNTs were performed using molecular dynamics (MD) simulations via material studio by Accelrys Inc. Maximum percentage reduction of 7.5 % in Young's modulus and increase in potential energy which is also accountable to stabilize carbon nanotubes (CNT), observed as 26.8%. Strain amplitude 0 .003 is employed and no of steps for each strain is 4. During the simulation 0.001 kcal/mol energy, 0.5 kcal/mol/A force, maximum number of iteration 500 with Steepest Descent Algorithm has been used. The fluctuation of the total energy and temperature during the MD were also calculated. This simulation carries an optimized structure before calculating the Young's modulus.