Properties of Fullerenes

In 1985, the story of carbon allotropes took a dramatic turn with the discovery of C60, which resulted in a new type of carbon structure, called the fullerenes (Kroto et al., 1985). This discovery earned the 1996 Nobel Prize in chemistry for Harold Kroto, Robert Curl, and 

There now are known to be a whole family of caged carbon structures having various numbers of carbon atoms, including C30, C50, C7o, C72, C76, Cg4, and the huge C540. The name fullerene has replaced the unwieldy, Buckminsterfullerene used to describe this general spheroid structure of carbon, although they still are referred to as Buckyballs . 

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. 

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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 structure-property relations of fullerenes, fullerene-derived solids, and carbon nanotubes are reviewed in the context of advanced technologies for carbon-hased materials. The synthesis, structure and electronic properties of fullerene solids are then considered, and modifications to their structure and properties through doping with various charge transfer agents are reviewed. Brief comments are included on potential applications of this unique family of new materials. 

Since the structure and properties of fullerene solids are strongly dependent on the structure and properties of the constituent fullerene molecules, we first review the structure of the molecules, which is followed by a review of the structure of the molecular solids formed from Ceo, C70 and higher mass fullerenes, and finally the structure of Cgo crystals. 

The friction and wear properties of fullerene LB fihns have been investigated. The coefficient of kinetic friction was measured using a steel ball-on-glass disk method, with the LB films deposited onto the glass disk [326,327]. The friction coefficient dropped from 0.8... 

Recently, photochemical and photoelectrochemical properties of fullerene (Cto) have been widely studied [60]. Photoinduced electron-transfer reactions of donor-Qo linked molecules have also been reported [61-63]. In a series of donor-Cfio linked systems, some of the compounds show novel properties, which accelerate photoinduced charge separation and decelerate charge recombination [61, 62]. These properties have been explained by the remarkably small reorganization energy in their electron-transfer reactions. The porphyrin-Qo linked compounds, where the porphyrin moieties act as both donors and sensitizers, have been extensively studied [61, 62]. 

Foote, C.S. Photophysical and Photochemical Properties of Fullerenes. 169,347-364 (1994). Fossey, J., Sorba, J., and Lefort, D. Peracide and Free Radicals A Theoretical and Experimental Approach. 164, 99-113 (1993). 

Guerin D, Lenfant S, Godey S, Vuillaume D (2010) Synthesis and electrical properties of fullerene-based molecular junctions on silicon substrate. J Mater Chem 20 2680-2690... 

Foote CS (1994) Photophysical and photochemical properties of fullerenes. Top Curr Chem 169 347-363. 

Pantarotto D, Tagmatarchis N, Bianco A, Prato M (2004) Synthesis and biological properties of fullerene-containing amino acids and peptides. Mini Rev Med Chem 4 805-814. 

For potentiation of photosensitizing properties of fullerenes C60 to the composition of their molecules antenna is being introduced, for example, porphyrine, and anthracenal (Arbogast and Foote, 1991). 

Compared to small two-dimensional molecules, for example the planar benzene, the structures of these three-dimensional systems are aesthetically appealing. The beauty and the unprecedented spherical architecture of these molecular cages immediately attracted the attention of many scientists. Indeed, Buckminsterfullerene CgQ rapidly became one of the most intensively investigated molecules. For synthetic chemists the challenge arose to synthesize exohedrally modified derivatives, in which the properties of fullerenes can be combined with those of other classes of materials. The following initial questions concerned the derivatiza-tion of fullerenes What kind of reactivity do the fullerenes have Do they behave like a three-dimensional superbenzene What are the structures of exohedral fullerene derivatives and how stable are they ... 

Addition reactions have the largest synthetic potential in fullerene chemistry. They also serve as a probe for screening the chemical properties of fullerene surfaces. 

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. 

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