相关论文: Structure and formation energy of carbon nanotube …
Understanding the role of cap structure during the nucleation and growth of single-walled carbon nanotubes (SWCNTs) is essential for achieving chirality-controlled synthesis. In this work, we propose a novel and intuitive algorithm to…
Carbon nanotubes have properties depending on the arrangement of carbon atoms on the tube walls, called chirality. Also it has been tried to grow nanotubes of only one chirality for more than a decade it is still not possible today. A…
Symmetric minima of surface potential energy of a nanocatalyst act as nucleation sites for chirally selective initial growth of single walled carbon tubes at low temperatures. The nucleation sites are sites of maximum coordination number of…
In this work we present ab initio calculations of the formation energies and stability of different types of multi-vacancies in carbon nanotubes. We demonstrate that, as in the case of graphene, the reconstruction of the defects has drastic…
We study the binding energy, intertube distance and electronic structure of bundles consisting of single walled carbon nanotubes of the same chirality. We model various nanotube structures (chiralities) and orientations with van der Waals…
Single-walled carbon nanotubes are hollow cylinders, that can grow centimeters long by carbon incorporation at the interface with a catalyst. They display semi-conducting or metallic characteristics, depending on their helicity, that is…
For the first time, an approach is suggested for the quantitative description of the electronic structure of single-walled carbon nanotubes and the prediction of active sites for the tube controlled functionalization in view of the tube…
The band structures of the periodic nanotube junctions are investigated by the effective mass theory and the tight binding model. The periodic junctions are constructed by introducing pairs of a pentagonal defect and a heptagonal defect…
We consider geometric constraints for the addition of carbon atoms to the rim of a growing nanotube. The growth of a tube proceeds through the conversion of dangling bonds from armchair to zigzag and vice versa. We find that the growth rate…
The importance of finite-size effects for the electronic structure of long zigzag and armchair carbon nanotubes is studied. We analyze the electronic structure of capped (6,6), (8,0), and (9,0) single walled carbon nanotubes as a function…
The electronic properties of carbon nanotubes are governed by their chirality, specified by the integer indices (n,m). While chirality-controlled synthesis has achieved notable successes, theoretical understanding remains predominantly…
We investigate the role of carbon nanotubes structure on their optical limiting properties. Samples of different and well-characterized structural features are studied by optical limiting and pump-probe experiments. The influence of the…
A theory of the long wavelength low energy electronic structure of graphite-derived nanotubules is presented. The propagating $\pi$ electrons are described by wrapping a massless two dimensional Dirac Hamiltonian onto a curved surface. The…
Chemical vapor deposition synthesis of single-walled carbon nanotubes experiments, using Fe catalyst, and alternating methane and carbon monoxide as carbon feedstocks, lead to the reversible formation of junctions between tubes of different…
We have made a systematic theoretical study to determine which are the most stable structures for substitutional nitrogen defects in carbon nanotubes, by making total energy calculations via DFT. These calculations were made for a (5,5) and…
Single-walled carbon nanotubes exist in a variety of different geometries, so-called chiralities, that define their electronic properties. Chiral selectivity has been reported in catalytic chemical vapor deposition synthesis experiments,…
We calculate the van der Waals energy of a C60 molecule when it is encapsulated in a single-walled carbon nanotube with discrete atomistic structure. orientational degrees of freedom and longitudinal displacements of the molecule are taken…
In order to accommodate an increasing demand for carbon nanotubes (CNTs) with desirable characteristics one has to understand the origin of helicity of their structures. Here, through in situ microscopy we demonstrate that the nucleation of…
A simple model for the nucleation and growth of single wall carbon nanotubes from a graphene sheet at the surface of a metallic catalyst saturated in carbon is developed. It enables to predict the geometry and energy of tube embryos of all…
We calculate the diameter and chirality dependences of the binding energies, sizes, and bright-dark splittings of excitons in semiconducting single-wall carbon nanotubes (SWNTs). Using results and insights from {\it ab initio} calculations,…