Theoretical Study for Electronic and Vibrational properties of nano cylinder (C140H28)

Abstract

Semi-empirical methods were applied for calculating the vibration frequencies and IR absorption intensities for normal coordinates of the (armchair nano cylinder) (C140H28) single wall carbon nanotube(SWCNT) at equilibrium geometry which was found to has D7d symmetry point group. Assignment of the modes of vibration (3N-6) was done depending on the pictures of their modes by applying (Gaussian 03) program. Comparison of the vibration frequencies of the nanotube which are active in IR, and inactive in Ramman spectra. For C-H stretching vibrations. The results show the relation for axial bonds, which are the vertical C-C bonds (annular bonds) in the rings and for circumferential bonds which are the outer ring bonds. Also include the assignment of puckering, breathing and clock-anticlockwise bending vibrations. They allow a comparative view of the charge density at the carbon atom too.