Stone–wales transformation in double-walled carbon nanotubes and the role of inner tube

Abstract

The Stone-Wales (SW) transformations in outer and inner tubes of double-walled carbon nanotubes (DWCNTs) have been studied using density functional theory (DFT)-based Becke’s three parameter hybrid exchange functional and Lee–Yang–Parr correlation functional (B3LYP) method. A comparative analysis of the SW transformation in DWCNT has been made with that in single-walled carbon nanotubes (SWCNTs) of similar chirality. Results reveal that both kinetic and thermodynamic feasibilities of SW transformation in SWCNTs dwindle down with a decrease in the curvature of the tubes. However, the feasibility of the same transformation in DWCNT initially increases and then decreases with a reduction in the curvature of the tube. Both π...π interactions between the two concentric tubes and the intertube distance play a vital role in SW transformation of outer tube of DWCNT. The important findings from this study are as follows: (i) the inner-tube can act as a catalyst in the SW transformation of the outer tube, (ii) the effect of the outer-tube on the SW transformation of DWCNT can be considered as a solid solvation, and (iii) the electron density of states (DOS) elicit that SW transformation in the outer-tube influences the conductivity of the DWCNT. In addition, the Car–Parrinello molecular dynamics (CPMD) simulations have also been carried out to understand the SW transformation and intramolecular reorganization.