TY - GEN
T1 - Theoretical studies of pentagon-heptagon pair defects in carbon nanotube junctions
AU - Shafiqzzaman, Md
AU - Udomvech, Anurak
AU - Kerdcharoen, Teerakiat
PY - 2007
Y1 - 2007
N2 - The electronic and energetic properties of topological defect in single-walled carbon nanotube junctions (SWCNTJ) were studied theoretically. The interfacial junction geometries can be constructed by fusing two zigzag tubes having different helicities and diameters. One segment of the fused nanotube is kept constant by using the (5,0) nanotube, while varying another segment from (6,0) to (10,0). Practically, the junctions are composed of one or more pentagon-heptagon pairs as defect in the perfect hexagonal lattice. The study shows that the electronic structures of SWCNTJ are dependent on the variation of diameter and length of carbon nanotubes. The HOMO and LUMO levels exhibit the even-odd "quantum size" oscillation of nanotube chiralities, even with increasing length of nanotubes. The energy gap that indicates metallic or semiconducting behavior depends on correlation between the tubes indices and tubule length. The energy of formation gently changes with the variation of tubular length and not diameter. The straight pair defect (5,0)//(6,0) SWCNTJ is more stable than other SWCNTJs. Comparison between the pair defect and the point defect structures shows that the straight SWCNTJ with topological pair defect has no affect by the alteration of numbers of pair defect structure around tube circumference. The outcome of this study would be of help as a knowledge base in the field of carbon nanotube molecular electronics.
AB - The electronic and energetic properties of topological defect in single-walled carbon nanotube junctions (SWCNTJ) were studied theoretically. The interfacial junction geometries can be constructed by fusing two zigzag tubes having different helicities and diameters. One segment of the fused nanotube is kept constant by using the (5,0) nanotube, while varying another segment from (6,0) to (10,0). Practically, the junctions are composed of one or more pentagon-heptagon pairs as defect in the perfect hexagonal lattice. The study shows that the electronic structures of SWCNTJ are dependent on the variation of diameter and length of carbon nanotubes. The HOMO and LUMO levels exhibit the even-odd "quantum size" oscillation of nanotube chiralities, even with increasing length of nanotubes. The energy gap that indicates metallic or semiconducting behavior depends on correlation between the tubes indices and tubule length. The energy of formation gently changes with the variation of tubular length and not diameter. The straight pair defect (5,0)//(6,0) SWCNTJ is more stable than other SWCNTJs. Comparison between the pair defect and the point defect structures shows that the straight SWCNTJ with topological pair defect has no affect by the alteration of numbers of pair defect structure around tube circumference. The outcome of this study would be of help as a knowledge base in the field of carbon nanotube molecular electronics.
KW - Carbon nanotube junction
KW - DFT
KW - Defect
UR - https://www.scopus.com/pages/publications/52949108008
U2 - 10.1109/NANO.2007.4601250
DO - 10.1109/NANO.2007.4601250
M3 - Conference contribution
AN - SCOPUS:52949108008
SN - 1424406080
SN - 9781424406081
T3 - 2007 7th IEEE International Conference on Nanotechnology - IEEE-NANO 2007, Proceedings
SP - 545
EP - 548
BT - 2007 7th IEEE International Conference on Nanotechnology - IEEE-NANO 2007, Proceedings
T2 - 2007 7th IEEE International Conference on Nanotechnology - IEEE-NANO 2007
Y2 - 2 August 2007 through 5 August 2007
ER -