Structural and electronic properties of single-wall BN nanotubes

The structural and electronic properties of armchair and zigzag models of s ingle-wall BN nanotubes have been investigated by performing semi-empirical molecular orbital self-consistent field calculations at the level of the A ustin Model 1 (AM1) method within the RHF formulation. It has been found th at these structures are stable and exothermic. The armchair model has a zer o net dipole moment, whereas the zigzag model has a nonzero net dipole mome nt. The interfrontier molecular energy gap of these systems are close to ea ch other, thus the gap is independent of the chirality of the tube. (C) 200 1 Elsevier Science B.V. All rights reserved.