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Fullerenes had been predicted for some time, but only after their accidental synthesis in 1985 were they detected in nature [3] [4] and outer space. [5] [6] The discovery of fullerenes greatly expanded the number of known allotropes of carbon, which had previously been limited to graphite, diamond, and amorphous carbon such as soot and charcoal.
Soot is produced by laser ablation of graphite or pyrolysis of aromatic hydrocarbons. Fullerenes are extracted from the soot with organic solvents using a Soxhlet extractor. [27] This step yields a solution containing up to 75% of C 60, as well as other fullerenes. These fractions are separated using chromatography. [28]
Graphite, named by Abraham Gottlob Werner in 1789, from the Greek γράφειν (graphein, "to draw/write", for its use in pencils) is one of the most common allotropes of carbon. Unlike diamond, graphite is an electrical conductor. Thus, it can be used in, for instance, electrical arc lamp electrodes.
Fullerene or C 60 is soccer-ball-shaped or I h with 12 pentagons and 20 hexagons. According to Euler's theorem these 12 pentagons are required for closure of the carbon network consisting of n hexagons and C 60 is the first stable fullerene because it is the smallest possible to obey this rule.
Besides unfilled fullerenes, endohedral metallofullerenes develop with different cage sizes like La@C 60 or La@C 82 and as different isomer cages. Aside from the dominant presence of mono-metal cages, numerous di-metal endohedral complexes and the tri-metal carbide fullerenes like Sc 3 C 2 @C 80 were also isolated. In 1999 a discovery drew ...
C 70 fullerene is the fullerene molecule consisting of 70 carbon atoms. It is a cage-like fused-ring structure which resembles a rugby ball, made of 25 hexagons and 12 pentagons , with a carbon atom at the vertices of each polygon and a bond along each polygon edge.
Since then, superconductivity has been reported in fullerene doped with various other alkali metals. [ 4 ] [ 5 ] It has been shown that the superconducting transition temperature in alkaline-metal-doped fullerene increases with the unit-cell volume V. [ 6 ] [ 7 ] As Cs + is the largest alkali ion, caesium-doped fullerene is an important ...
The defect is named after Anthony Stone and David J. Wales at the University of Cambridge, who described it in a 1986 paper [5] on the isomerization of fullerenes.However, a similar defect was described much earlier by G. J. Dienes in 1952 in a paper on diffusion mechanisms in graphite [6] and later in 1969 in a paper on defects in graphite by Peter Thrower. [7]