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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.
Fullerenes are a class of carbon allotropes that were first discovered in 1985 and are also an example of macromolecular cages. Buckminsterfullerene (C 60) and the 60 atoms of this molecule are arranged in a cage-like structure and the framework resembles a soccer ball; the molecule has an icosahedral symmetry.
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. A related fullerene molecule, named buckminsterfullerene (or C 60 fullerene) consists of 60 carbon atoms.
Additional atoms, ions, clusters, or small molecules can be trapped inside fullerenes to form inclusion compounds known as endohedral fullerenes. An unusual example is the egg-shaped fullerene Tb 3 N@ C 84, which violates the isolated pentagon rule. [60]
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 ...
They are named for the resemblance to the geodesic structures devised by Richard Buckminster "Bucky" Fuller. Fullerenes are positively curved molecules of varying sizes composed entirely of carbon, which take the form of a hollow sphere, ellipsoid, or tube (the C60 version has the same form as a traditional stitched soccer ball).
Ancient giant stromatolites used to be widespread in Earth’s Precambrian era, which encompasses the early time span of around 4.6 billion to 541 million years ago, but now they are sparsely ...
A network solid or covalent network solid (also called atomic crystalline solids or giant covalent structures) [1] [2] is a chemical compound (or element) in which the atoms are bonded by covalent bonds in a continuous network extending throughout the material.