We present first principles calculations of the electronic structure of small carbon nanotubes with different chiral angles theta and different diameters (d<1 nm). Results are obtained with a full potential method based on the density functional theory (DFT), with the local density approximation (LDA). We compare the band structure and density of states (DOS) of chiral nanotubes with those of z...

Carbon nanotubes provide a unique system for studying one-dimensional quantization phenomena. Scanning tunneling microscopy was used to observe the electronic wave functions that correspond to quantized energy levels in short metallic carbon nanotubes. Discrete electron waves were apparent from periodic oscillations in the differential conductance as a function of the position along the tube ax...

Structurally uniform and chirality-pure single-wall carbon nanotubes are highly desired for both fundamental study and many of their technological applications, such as electronics, optoelectronics, and biomedical imaging. Considerable efforts have been invested in the synthesis of nanotubes with defined chiralities by tuning the growth recipes but the approach has only limited success. Recentl...

This paper discusses several important issues in a molecular dynamics simulation for analysing carbon nanotubes and their mechanical properties. In particular, the paper addresses the problems in selecting appropriate inter-atomic potentials, number of thermostat atoms, thermostat techniques, time and displacement steps and number of relaxation steps to reach the dynamic equilibrium. Based on t...

Spin polarized density functional theory has been used to investigate the structural stability and electronic properties of extrinsic and intrinsic defects in boron nitride nanotubes. Carbon substitutional defects under nitrogen rich and boron-rich growth conditions have the lowest heats of formation compared to boron and nitrogen antisites. Creating a defect reduces the band gap of the nanotub...

The merit of various kinds of carbon nanotubes as field electron emission cathode materials has been studied. The field electron emission characteristics of electrophoretically deposited films of single walled carbon nanotubes, multiwalled carbon nanotubes of diameter between 10 and 20 and .50 nm and carbon nanofibres with diameters between 200 and 600 nm were investigated. Results of the measu...

We report structural, elastic, and electronic properties of selected, deformed, single-wall carbon nanotubes under uniaxial strain. We utilized a generalized gradient approximation potential of density functional theory and the linear combination of atomic orbital formalism. We discuss bond-lengths, tubule radii, and the band gaps as functions of tension and compression strain for carbon nanotu...

Light membranes composed of single-walled carbon nanotubes (SWNTs) can serve as efficient nanoscale vessels for encapsulation of tetrafluoromethane at 300 K and operating external pressure of 1 bar. We use grand canonical Monte Carlo simulation for modeling of CF4 encapsulation at 300 K and pressures up to 2 bar. We find that the amount of adsorbed CF4 strongly depends on the pore size in nanot...