Fullerenes physical properties

Physical properties of Fullerene C q. It does not melt below 360°, and starts to sublime at 300° in vacuo. It is a mustard coloured solid that appears brown or black with increasing film thickness. It is soluble in common organic solvents, particularly aromatic hydrocarbons which give a beautiful magenta colour. Toluene solutions are purple in colour. Sol in (5mg/mL), but dissolves slowly. Crysts of C o are both needles and plates. 

Physical properties of Fullerene Cyg It does not melt below 360°, and starts to sublime at 350° in vacuo. A reddish-brown solid, greenish black in thicker films. Solns are port-wine red in colour. Mixtures of Csq and C70 are red due to C70 being more intensely coloured. It is less soluble than Cso in but also dissolves... 

The most extensive calculations of the electronic structure of fullerenes so far have been done for Ceo- Representative results for the energy levels of the free Ceo molecule are shown in Fig. 5(a) [60]. Because of the molecular nature of solid C o, the electronic structure for the solid phase is expected to be closely related to that of the free molecule [61]. An LDA calculation for the crystalline phase is shown in Fig. 5(b) for the energy bands derived from the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) for Cgo, and the band gap between the LUMO and HOMO-derived energy bands is shown on the figure. The LDA calculations are one-electron treatments which tend to underestimate the actual bandgap. Nevertheless, such calculations are widely used in the fullerene literature to provide physical insights about many of the physical properties. 

Preparation research of SWCNT was also put forth by lijima and his co-worker [3]. The structure of SWCNT consists of an enrolled graphene to form a tube without seam. The length and diameter depend on the kinds of the metal catalyst used in the synthesis. The maximum length is several jim and the diameter varies from 1 to 3 nm. The thinnest diameter is about the same as that of Cgo (i.e., ca. 0.7 nm). The structure and characteristics of SWCNT are apparently different from those of MWCNT and rather near to fullerenes. Hence novel physical properties of SWCNT as the one-dimensional material between molecule and bulk are expected. On the other hand, the physical property of MWCNT is almost similar to that of graphite used as bulk [6c]. 

Dresselhaus, M. S., Dresselhaus, G. and Ekiund, P. C., Science of Fullerenes and Carbon Nanotubes, Academic Press, New York, NY, 1996. Salto, R., Dresselhaus, M. S. and Dresselhaus, G., Physical Properties of Carbon Nanotubes, Imperial College Press, London, 1998. 

In addition to chemical or physical properties, a fascinating aspect of fullerene related materials is their central empty space, where atoms, molecules or particles can be enclosed. The enclosed particles are then protected by the robust graphitic layers from chemical or mechanical effects. The very long cavities of CNTs have a special potential due to their high aspect ratio and they can be used as templates to fabricate elongated nanostructures. 

Of all the fullerene forms, the nearly spherical properties of C o have attracted the greatest attention, especially in the field of bioconjugation. In addition to its physical properties, C o fullerenes have unique photo-optical and electro-chemical properties, which make them useful as carriers for biomedical research applications. For instance, upon exposure to light C o will generate singlet oxygen, which can be used in vivo to cleave biological molecules, particularly DNA and RNA. Studies indicate that irradiation of Cgo in solution can be used to destroy virus contamination (Kasermann and Kempf, 1997). Solutions of Buckminsterfullerene are a deep purple color, whereas other sizes of fullerenes display a variety of other colors. 

Methanesulfonyl chloride, 23 653, 681-683 Methano[60]fullerenes, 12 242 Methanogenic conditions, defined, 3 757t Methanoic acid, physical properties, 5 29t Methanol, 16 299-316. See also Methanol synthesis... 

It is exciting to study the progression of the chemical and physical properties of these systems as a function of their size to determine at what stage (if any) these hydrocarbons begin to behave like the all-carbon cages. That is, these curved polynuclear aromatics may serve as models for the fullerenes. 

Investigations of physical properties in solution as well as in the solid state have been predominantly carried out on C q, and to a minor extent on C70, since these are the most abimdant fullerenes. Currently, little material is available for the higher fullerenes or endohedrals, because it takes about 250 h to produce 1 mg of any of these [269]. 

It is therefore the right time to give a first comprehensive overview of fullerene chemistry, which is the aim of this book. This summary addresses chemists, material scientists and a broad readership in industry and the scientific community. The number of publications in this field meanwhile gains such dimensions that for nonspecialists it is very difficult to obtain a facile access to the topics of interest. In this book, which contains the complete important literature, the reader will find all aspects of fullerene chemistry as well as the properties of fullerene derivatives. After a short description of the discovery of the fullerenes all methods of the production and isolation of the parent fullerenes and endohedrals are discussed in detail (Chapter 1). In this first chapter the mechanism of the fullerene formation, the physical properties, for example the molecular structure, the thermodynamic, electronic and spectroscopic properties as well as solubilities are also summarized. This knowledge is necessary to understand the chemical behavior of the fullerenes. 

V. S. Kuck (eds.), Fullerenes Synthesis, Properties, and Chemistry of Large Carbon Clusters, ACS Symp. Ser. 481, American Chemical Society, Washington, D.C., 1992 H. W. Kroto and D. R. M. Walton (eds.), Fullerenes New Horizons for the Chemistry, Physics, and Astrophysics of Carbon. Cambridge Univ. Press, Cambridge, 1993 H. W. Kroto (ed.), Fullerenes. Pergamon/Elsevier, London, 1993 A. Hirsch, The Chemistry of the Fullerenes. Thieme Verlag, Stuttgart, 1993 H. Aldersley-Williams, The Most Beautiful Molecule Discovery of the Buckyball. Wiley, New York, 1995. 

Fujitani, Y., Kobayashi, T., Arashidani, K., Kunugita, N. and Suemura, K. (2008) Measurement of the physical properties of aerosols in a fullerene factory for inhalation exposure assessment /. Occup. Environ. Hyg., 5 (6), 380-389. 

In 1991, Foote et al. [20,21] carried out the first investigations of basic photophysical properties of pure fullerenes. Since then research has lead to extensive knowledge about the photophysical behavior of the fullerenes in general [22-48], Scheme 1 shows the main photophysical processes. The most relevant photo physical properties are summarized in Table 1. 

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