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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.
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.
In organic chemistry, spherical aromaticity is formally used to describe an unusually stable nature of some spherical compounds such as fullerenes and polyhedral boranes. In 2000, Andreas Hirsch and coworkers in Erlangen , Germany , formulated a rule to determine when a spherical compound would be aromatic .
Spherical fullerenes are also called buckyballs, and they resemble the balls used in football (soccer). Fullerenes are similar in structure to graphite, which is composed of stacked graphene sheets of linked hexagonal rings; but they may also contain pentagonal (or sometimes heptagonal) rings.
Fullerenes are sparingly soluble in aromatic solvents and carbon disulfide, but insoluble in water. Solutions of pure C 60 have a deep purple color which leaves a brown residue upon evaporation. The reason for this color change is the relatively narrow energy width of the band of molecular levels responsible for green light absorption by ...
Alternatively, endohedral hydrogen fullerenes can be produced by opening and closing a fullerene by organic chemistry methods. A recent example of endohedral fullerenes includes single molecules of water encapsulated in C 60. [10] Noble gas endofullerenes are predicted to exhibit unusual polarizability.
Today's Wordle Answer for #1273 on Friday, December 13, 2024. Today's Wordle answer on Friday, December 13, 2024, is BOXER. How'd you do? Next: Catch up on other Wordle answers from this week.
Unlike diamond, graphite is an electrical conductor. Thus, it can be used in, for instance, electrical arc lamp electrodes. Likewise, under standard conditions, graphite is the most stable form of carbon. Therefore, it is used in thermochemistry as the standard state for defining the heat of formation of carbon compounds.