Stacking characteristics of graphene shells in carbon nanotubes

Abstract

Intershell spacings between carbon nanotubes ${\stackrel{^}{d}}_{002}$ ranging from 3.59 \AA{}A to 3.62 \AA{}A, with an uncertainty of \ifmmode\pm\else\textpm\fi{}0.06 \AA{}A, are deduced by using the in-plane C-C bonding length in the graphene hexagonal network as an internal calibration standard for the digital image analysis of TEM lattice images. These large ${\stackrel{^}{d}}_{002}$ values imply weak intershell correlation between carbon atoms on adjacent tubules. By using the measured ${\stackrel{^}{d}}_{002}$ values and the finite number of possible nanotubes, a determination of the chiral vector is made for two shells within a multiwall nanotube. The connection between constraints on ${\stackrel{^}{d}}_{002}$ and the self-assembly of multilayer carbon nanotubes is discussed.