Atomic resolution STM imaging of a twisted single-wall carbon nanotube

We present atomically resolved scanning tunneling microscopy images of single-wall carbon nanotubes (SWNT's) embedded in a crystalline nanotube rope. Although they may be interpreted as of a chiral nanotube, the images are more consistently explained as an achiral armchair tube with a quenched twist distortion. The existence of quenched twists in SWNT's in ropes might explain the fact that both as-grown bulk nanotube material and individual ropes have insulatorlike conductivity at low temperature.