Stability of Small Boron Nitride Nanotubes

Molar Binding Energy of Zigzag and Armchair Single-Walled Boron Nitride Nanotubes

“…n n R , of the zigzag and armchair, (n,0) and (n,n), BN nanotubes in terms of the index and the structure parameter a were obtained [87]. The parameter a corresponds to the lattice constant of the boron nitride layered crystals, i.e., intralayer B-B or N-N bonds lengths.…”

“…In view of these factors, from the calculated singlewalled nanotubes [87] pairs most suitable for the formation of the stable double-walled BN nanotubes have been chosen. Remaining small divergences in sizes of the neighboring regular nanotubes can be compensated by defects and small chiral distortions.…”

“…This task has been solved in [87,108,109] for regular (achiral), i.e., zigzag (n,0) and armchair (n,n) BN nanotubes. A model of regular nanotubes used here assumes that all atomic sites are located on cylindrical surface at the vertexes of regular hexagons broken along B-N or B-B and N-N diagonals, i.e., the expected small differences in bond length distinguished by their orientation toward the tube axis are neglected.…”

“…A model of regular nanotubes used here assumes that all atomic sites are located on cylindrical surface at the vertexes of regular hexagons broken along B-N or B-B and N-N diagonals, i.e., the expected small differences in bond length distinguished by their orientation toward the tube axis are neglected. Namely, radii ( ,0) n R and ( , ) n n R of the zigzag and armchair nanotubes have been obtained [87,108] in terms of the nanotube index 1, 2,3,... n  and the structure parameter a :…”

“…Detailed regular geometries of zigzag and armchair BN nanotubes have been described in [108,109] using cylindrical coordinates ( , , ) z   , which are useful for calculating binding energy. A unit cell of zigzag nanotubes consists of 4 atomic rings in parallel planes perpendicular to the axis.…”