Generation of open ends carbon nanotubes coordinates (atomic positions) is easy and the generation of cap for these carbon nanotubes is extremely difficult. Some of the half-fullerenes (C60, C240, C540…) fit as a cap for the armchair and zigzag nanotubes. NanotubeModeler  (http://www.jcrystal.com/products/wincnt/index.htm) software generates the carbon nanotubes with cap but they are limited to few armchair and zigzag configurations.

Hi All, Simulations and experimental results show the wide range of values for Young’s modulus (0.5 to 5.5 TPa) and wall thickness (0.066 to 0.34 nm) of carbon nanotubes (CNTs) in literature. Most of the published results say that the set of values (Young’s modulus and wall thickness of CNT) are 1 TPa  and 0.34 nm, and the product is around 0.34 TPa-nm. In my point of view this set of values may be appropriate for multi-walled carbon nanotubes. Can we use the same set of values for analysis of single-walled carbon nanotubes (SWCNTs)?  The interlayer distance between the graphene layers is 0.34 nm. Can we use this value as wall thickness of SWCNT or do we need to use atomic thickness instead of 0.34 nm?