Spectroscopic Properties of Carbon Nanotubes

Not only the electronic and magnetic characteristics, but also the spectroscopic properties of carbon nanotubes are of special interest On one hand, the utilization of these features raises hopes for various applications, but, for being quasi-one-dimensional objects, they might also serve to a deeper understanding of numerous spectroscopic phenomena. 

The model of permitted wave vectors and the concept of reciprocal space (Section 

4) that both proved their worth in the discussion of electronic properties are as well suitable to describe a number of spectroscopic features. Especially those phenomena that are based on the behavior of phonons can be treated this way. 

The essential spectroscopic properties will be presented in the following. In most cases, a stringent mathematical and physical deduction will be omitted as there is a multitude of monographs and reviews on that topic, and it would be far beyond the scope of this introductory text. 

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Besides the electronic and spectroscopic properties of carbon nanotubes, their thermal behavior is of interest, too. Most of aU a distinct anisotropy should be observed. The thermal behavior is predominantly governed by the phonon proper-hes of the sample. With the density of phonon states being available from theoretical considerations, it is possible to compare these expectation values directly to the experimental results. Again, however, it is true that exact assignment and explana-hon of phenomena require measurements of single nanotubes whose structure has been determined. This is some challenge for the time being. 

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. 

Besides those spectroscopic properties presented so far, there is a variety of further phenomena that have been studied on carbon nanotubes, either in experiment or... 

This book describes the applications of important new NMR spectroscopic methods to a variety of useful materials and compares them with results from other techniques such as adsorption, differential scanning calorimetry, thermally stimulated depolarization cmrent, dielectric relaxation spectroscopy, infrared spectroscopy, optical microscopy, and small-angle and wide-angle x-ray scattering. The text explores the application of NMR spectroscopy to examine interfacial phenomena in objects of increasing complexity, beginning with immodified and modified silica materials. It then describes properties of various mixed oxides with comparisons to individual oxides and also describes carbon materials such as graphite and carbon nanotubes. 

Chipara Mircea, Cruz Jessica, Vega Edgar, R., Alarcon Jorge, Mion Thomas, Chipara Dorina Magdalena, Ibrahim, A., Tidrow Steven, Hui David. Polyvinylchloride-Single Walled Carbon Nanotube Composites Thermal and Spectroscopic Properties, Special Issue Synthesis, Properties, and Applications of Polymeric Nanocomposites. Journal of Nanomaterials, Article ID 435412,6 pp, 2012. 

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