An approach to control the radius and the chirality of nanotubes

The success of future nanotechnologies will strongly depend on our ability to control the structure of materials on the atomic scale. For carbon nanotubes it turns out that one of their structural parameters - the chirality - may not be controlled during synthesis. We explain the basic reason for this defect and show that novel classes of nanotubes like boron nanotubes, which are related to sheets with anisotropic in-plane mechanical properties, could actually overcome these problems. Our results further suggest that extended searches for nanomaterials similar to pure boron might allow for one of the simplest and most direct ways to achieve structural control within nanotechnology.