Author/Authors :
Yurii E. and Poklonski، نويسنده , , Nikolai A. and Ratkevich، نويسنده , , Sergey V. and Vyrko، نويسنده , , Sergey A. and Kislyakov، نويسنده , , Eugene F. and Bubel’، نويسنده , , Oleg N. and Popov، نويسنده , , Andrei M. and Lozovik، نويسنده , , Yurii E. and Hieu، نويسنده , , Nguyen Ngoc and Viet، نويسنده , , Nguyen Ai Viet، نويسنده ,
Abstract :
The atomic and band structures of the (6, 0) zigzag carbon nanotube at its axial elongation are calculated by semiempirical molecular orbital and by tight-binding methods. The ground state of the nanotube is found to have a Kekule structure with four types of bonds and difference between lengths of long and short bonds of about 0.005 nm. The structural phase transition is revealed at ≈ 9 % elongation, resulting in a quinoid structure with two types of bonds. This structural phase transition is followed by the transition from a narrow gap to moderate gap semiconductor. Validity of the semiempirical PM3 method is discussed.
