Lc. Qin et al., HELICITY AND PACKING OF SINGLE-WALLED CARBON NANOTUBES STUDIED BY ELECTRON NANODIFFRACTION, Chemical physics letters, 268(1-2), 1997, pp. 101-106
Electron nanodiffraction patterns from raft-like bundles of single-wal
led carbon nanotubes have been obtained to analyze the helicity distri
bution and the packing of the tubules. In most cases, the helical angl
es were found to be quite evenly distributed, ranging from the zigzag
structure of 0 degrees helicity to the armchair structure of 30 degree
s helicity. Examples of preferred helicities were encountered occasion
ally, such as bundles of tubules of almost single-helicity, correspond
ing to the armchair structure. The lattice constant of the hexagonally
packed bundles varied and two example values were determined to be 1.
64 nm and 1.71 nm, respectively.