Fullerenes discovery

After the discovery of fullerenes [10] the family of carbon based nanostructures has been constantly growing (see Fig. 3). Fullerene discovery was followed by... 

The discovery of perfect geodesic dome closed structures of carbon, such as C o has led to numerous studies of so-called Buckminster fullerene. Dislocations are important features of the structures of nested fullerenes also called onion skin, multilayered or Russian doll fullerenes. A recent theoretical study [118] shows that these defects serve to relieve large inherent strains in thick-walled nested fullerenes such that they can show faceted shapes. 

Thus far the importance of carbon cluster chemistry has been in the discovery of new knowl edge Many scientists feel that the earliest industrial applications of the fullerenes will be based on their novel electrical properties Buckminsterfullerene is an insulator but has a high electron affinity and is a superconductor in its reduced form Nanotubes have aroused a great deal of interest for their electrical properties and as potential sources of carbon fibers of great strength... 

Regarding a historical perspective on carbon nanotubes, very small diameter (less than 10 nm) carbon filaments were observed in the 1970 s through synthesis of vapor grown carbon fibers prepared by the decomposition of benzene at 1100°C in the presence of Fe catalyst particles of 10 nm diameter [11, 12]. However, no detailed systematic studies of such very thin filaments were reported in these early years, and it was not until lijima s observation of carbon nanotubes by high resolution transmission electron microscopy (HRTEM) that the carbon nanotube field was seriously launched. A direct stimulus to the systematic study of carbon filaments of very small diameters came from the discovery of fullerenes by Kroto, Smalley, and coworkers [1], The realization that the terminations of the carbon nanotubes were fullerene-like caps or hemispheres explained why the smallest diameter carbon nanotube observed would be the same as the diameter of the Ceo molecule, though theoretical predictions suggest that nanotubes arc more stable than fullerenes of the same radius [13]. The lijima observation heralded the entry of many scientists into the field of carbon nanotubes, stimulated especially by the un-... 

The hoped-for applications of fullerenes have not materialised as yet. A cartoon published in America soon after the discovery shows a hapless hero sinking into a vat full of buckyballs (another name for fullerenes) with their very low friction. It is not known how the hero managed to escape... 

In the theoretical carbon nanotube literature, the focus is on single-wall tubules, cylindrical in shape with caps at each end, such that the two caps can be joined together to form a fullerene. The cylindrical portions of the tubules consist of a single graphene sheet that is shaped to form the cylinder. With the recent discovery of methods to prepare single-w alled nanotubes[4,5), it is now possible to test the predictions of the theoretical calculations. 

The synthesis of molecular carbon structures in the form of C q and other fullerenes stimulated an intense interest in mesoscopic carbon structures. In this respect, the discovery of carbon nanotubes (CNTs) [1] in the deposit of an arc discharge was a major break through. In the early days, many theoretical efforts have focused on the electronic properties of these novel quasi-one-dimensional structures [2-5]. Like graphite, these mesoscopic systems are essentially sp2 bonded. However, the curvature and the cylindrical symmetry cause important modifications compared with planar graphite. 

As with the fullerenes, further detailed studies will depend on the discovery of viable bulk preparations of the met-cars. Macroscopic... 

R. F. Curl (Rice University, Texas), H. Kroto (Sussex University) and R. E. Smalley (Rice University, Texas) discovery of a new form of carbon, the fullerenes. 

Since the discovery of buckminsterfullerene (C o) [85NAT(318)162] and other fullerenes (Cig. C70), these molecules have been intensely studied, both experimentally and theoretically. Likewise, several reports on heterofullerenes containing heteroatoms such as nitrogen and boron have appeared (91JPC4948 91JPC10564). The incorporation of heteroatoms is expected to modify the structural and electronic features of these structures, and have thus attracted some interest. 

Billups, W. E. Ciufolini, M.A. (Eds.) Buckminsterfullerenes, VCH, NY, 1993 Taylor, R. (Ed.) The Chemistry of Fullerenes, World Scientific, River Edge, NJ, Singapore, 1995 Aldersey-Williams, H. The Most Beautiful Molecule The Discovery of the Buckyball ... 

The following is a comprehensive smwey of the chemistry of macrocycles comprised entirely of phenyl and acetylenic moieties. Although over fom" decades old, this area of research has come into its own just in the last few years. Widespread interest in the field has been spurred by recent discoveries utilizing these compoimds as ligands for organometallic chemistry, hosts for binding guest molecules, models of synthetic carbon allotropes, and precursors to fullerenes and other carbon-rich materials. This review will discuss the preparation of a tremendous variety of novel structm-es and detail the development of versatile synthetic methods for macro cycle construction. 

The Nobel prize in Chemistry for the year 1996 was awarded for the discovery of the fullerenes, the third allotropic form of carbon, with Cgo and C70 as the two most prominent representatives. While the fullerenes of course are the epitome of carbon-rich molecular compounds, it is an irony that their synthesis is more of a physical phase transition, taking place under drastic conditions [1]. 

Not too long ago, graphite and diamond were the only two known modifications of carbon. That changed dramatically with the discovery of in 1985 and all the higher fullerenes soon thereafter. Nevertheless, this breakthrough did not stand alone in paving the way to the new era of chemical and physical research into carbon rich compounds that we are now enjoying. 

As is well known, many experimental smdies have been made extensively to search for a possibility of encapsulation of atoms by hollow fullerenes since the discovery of Cgo by Kroto et al. [143]. These methods, however, usually require high tempratures and high pressures, or ion implantation. The yields are also as low as 0.4—10 %. In this sense, the efficiency in our case is much higher and the required conditions are much milder with collison energy of 2 eV. However, the boron substimtion is a bottle neck, although Smalley and co-workers successfully synthesized boron-doped fullerenes [144]. 

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... 

Concept With the discovery of the fullerenes, it has become evident that elemental carbon can exist in almost an infinite number of stable allotropes that are either molecular or polymeric in nature. Whereas achiral and chiral fullerenes can now be prepared in bulk quantities and methods for their regio- and stereoselective multiple functionalization are being developed in increasing numbers, the... 

Abstract The past two decades have profoundly changed the view that we have of elemental carbon. The discovery of the fullerenes, spherically-shaped carbon molecules, has permanently altered the dogma that carbon can only exist in its two stable natural allotropes, graphite and diamond. The preparation of molecular and polymeric acetylenic carbon allotropes, as well as carbon-rich nanometer-sized structures, has opened up new avenues in fundamental and technological research at the interface of chemistry and the materials sciences. This article outlines some fascinating perspectives for the organic synthesis of carbon allotropes and their chemistry. Cyclo[n]carbons are the first rationally designed molecular carbon allotropes, and... 

Following the discovery of a bulk fullerene preparation process in 1990, the covalent chemistry of these carbon allotropes has developed at a phenomenal pace. Frontier orbital (LUMO) and tether-directed functionalization concepts have been successfully applied to the regio- and stereoselective preparation of multiple covalent adducts of C60. These have found increasing applications in the construction of functional supramol-ecules. More recently, the sequence of Bingel reaction - retro-Bingel reaction has provided an elegant access to isomerically pure higher fullerenes and, in particular, to pure carbon enantiomers. 

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