Armchair SWCNTs Geometrical Parameters and Energy Sub-Bands: A First-Principles Study

Simulating the properties of carbon nanotubes is a useful method to identify their essence and simplify the usage of these nanostructures in nanotechnology applications. In this study the Full-Potential Linearized Augmented Plane Wave (FP-LAPW) method with the Local Density Approximation (LDA) for the exchange-correlation potential using WIEN2k software were carried out to calculate the geometrical parameters and electronic sub-bands of (7, 7) single-walled carbon nanotubes. In this work we have been illustrate the effect of chirality on the number of degenerate and non-degenerate sub-bands in band structures of armchair carbon nanotubes. The geometrical parameters such as diameter and circumference and the electronic structure comprise energy sub-bands of CNTs (7,7) have been investigated. Results show that the chemical bonding of C-C in these carbon nanotubes is mainly covalent and the diameter and circumference of these carbon nanotubes are equal to 9.358 angstrom and 29.393 angstrom respectively which show a favorable agreement with the experimental results.