What is the formula for fullerene

Fullerene

Plural: fullerenes

Fullerenes are a carbon modification or a special group of macromolecules of composition C consisting exclusively of carbon2n. They are the third carbon modification besides graphite and diamond. Fullerenes are polyhedra made of more than n three-coordinate carbon atoms. They occur naturally and / or are produced artificially.

They were discovered in 1985 by Curl, Kroto and Smalley, who received the 1996 Nobel Prize in Chemistry.

The best known and most stable fullerenes have the sum formulas C.60, C70, C76, C80, C82, C84, C86, C90 and C94. Which is best researched C.60, which consists of 12 pentagons and 20 hexagons (icosahedral symmetry); (also named Buckminster Fullerene, in honor of the US architect Buckminster Fuller, who became known for his geodesic domes). In 2005, a working group at the University of Freiburg succeeded in finding the smallest fullerene C.20 to prove. This carbon cluster is a dodecahedron made up only of five-membered rings (i.e., the smaller brother of the well-known C.60.)


properties

Fullerenes are usually brownish-black powders with a metallic sheen, which disintegrate into graphite in air. As a mineral fullerite (C.60) black to brown, density 1.9 - 2.0, opaque, as brittle to mussel-like fragments, microscopic crystals in spherical aggregates; Hardness 3.5, black line. Crystal system: Tetragonal-Ditetragonal Dipyramidal; Space group: pseudocubic. (Truncated icosahedron; pentakis dodecahedron with 32 faces (20 hexagons, 12 pentagons), 60 vertices and 90 edges.

Fullerenes can also store helium as clathrates (inclusion / inclusion compounds)


Natural occurrence

Natural fullerenes come (among other things) in the form of the mineral fullerite (not yet submitted to the IMA, but described in detail) (C.60) in different rocks.

  1. In Shungite: (Metamorphic Precambrian Greenschist facies in Karelia, Russia)
  2. In the Cretaceous-Tertiary Boundary Layers (New Zealand)
  3. In meteorites and sediments of meteoritic impacts (Gissar, Tajikistan)
  4. In substrates with a high carbon content, caused by lightning strikes

as well as in interstellar space and in soot.


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