Structure of Single-Walled Carbon Nanotubes

The diameter of the carbon nanotube can easily be calculated from the absolute length of vector C that represents the circumference (Eqs. 3.2 and 3.3). The two unit vectors and U2 measure 0.246nm each (a). Circumference and diameter thus are calculated to be 

The size of the elemental cell may as well be calculated from the descriptors. There are two possible formulas to be applied depending on the relation of the values for n and m. With the difference of n and m being an integer multiple x of 3g g = biggest common divisor of n and m), the absolute value of T is obtained from Eq. (3.5)  

The number of carbon atoms in the unit cell of a nanotube depends on its structure and may be anything up to several thousands. Again the respective mathematical expressions depend on the relation of n and m (Eq. 3.7)  

These values may grow large even for carbon nanotubes with typical diameters of 2-30 nm. A (95,51)-nanotube, for instance, has a diameter of 10.05 nm, its unit cell nevertheless measures 54.7 nm already and contains 65 884 carbon atoms. 

Many of these translational unit cells are lined up in axial direction in real nanotubes. Their length thus can differ from their diameter by orders of magnitude. For this structural particularity (the expansion being wider than just a few nanometers in one direction only), carbon nanotubes may also be considered onedimensional crystals, which largely influences their spectroscopic and electronic properties as will be discussed in more detail in the ensuing chapters. 

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Electronic Structures of Single-Walled Carbon Nanotubes... 

Kavan L, Rapta P, Dunsch L et al (2001) Electrochemical tuning of electronic structure of single-walled carbon nanotubes in-situ Raman and Vis-NIR study. J Phys Chem B 105 10764-10771... 

FIGURE 2.35 Schematic illustration of the various structures of single-wall carbon nanotube. 

H.S. Jeong, Y.K. Ko, Y.H. Kim, D.K. Yoon, H.-T. Jung, Self assembled plate-like structures of single-walled carbon nanotubes by non-covalent hybridization with smectic hquid crystals. Carbon 48, 774-780 (2010)... 

Bower, C., Zhou, O., and Wu, Y. Electronic structure of single-walled carbon nanotubes determined by NMR. 2000 288 492-494. 

M.S. Strano, C.A. Dyke, M.L. Usrey, P.W. Barone, MJ. Allen, H. Shan, C. Kittrell, R.H. Hauge, J.M. Tour, R.E. Smalley, Electronic structure control of single-walled carbon nanotube functionalization. Science 301, 1519-1522 (2003). 

Odom, T. W. Huang, J.-L. Kim, R Lieber, C. M. 1998. Atomic structure and electronic properties of single-walled carbon nanotubes. Nature 391 62-64. 

Bachilo SM, Strano MS, Kittrell C, Hauge RH, Smalley RE, Weisman RB (2002) Structure-assigned optical spectra of single-walled carbon nanotubes. Science 298 2361-2366. 

M. Rahmandoust, A. Ochsner, Influence of structural imperfections and doping on the mechanical properties of single-walled carbon nanotubes., Journal of Nano Research, vol. 

As a third group of fullerene-like systems whose synthetic development is identified as a major future challenge are structurally defined single-walled carbon nanotubes (SWNTs) with uniform helicity and length, including their covalent and non-covalent derivatives. SWNTs can be considered as elongated giant fullerenes. 

In section 11D, we showed the sensitivity of TERS to distinguish different molecules by focusing on characteristic vibration modes of each molecule. In this section, we show another capability of TERS to characterize the structural difference of single-walled carbon nanotubes (SWNTs) as a sample. 

Alvarez, L., Righi, A., Guillard, T., Rols, S., Anglaret, E., Laplaze, D., and Sauvajol, J. L. 2000. Resonant Raman study of the structure and electronic properties of single wall carbon nanotubes. Chem. Phys. Lett. 316 186-90. 

T.C. Dinadayalane, J. Leszczynski, Toward Nanomaterials Structural, Energetic and Reactivity Aspects of Single-Walled Carbon Nanotubes, in Nanomaterials Design and Simulation, ed. by P.B. Balbuena, J.M. Seminario (Elsevier, Amsterdam, 2007), p. 167... 

A brand new area should conclusively be mentioned, that of the PP-nanocomposites made of single-walled carbon nanotubes [157] or silica nanoparticles [158] which were reported to facilitate the growth of the -crystalline structure. However, no published data support their supposed outstanding performance. 

There is yet another phenomenon that points to a 1,4-addition of fluorine atoms occurring at least partially The products obtained from the reaction of single-walled carbon nanotubes with fluorine are definite nonconductors (resistance >20 MQ), while the nanotubes employed feature a resistance of 10-15 2 only. Considering the structures that result from a consecutive 1,2- or 1,4-addition of fluorine, respectively, reveals that an electric current via conjugated it-bonds would still be possible in the 1,2-adduct (Figure 3.70). In the 1,4-adduct, on the other... 

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