C70 fullerene is the fullerene molecule consisting of 70 carbon atoms. C70 Fullerenes are closed hollow cages consisting of carbon atoms interconnected in pentagonal and hexagonal rings having a cage-like fused-ring structure which resembles a rugby ball. Each carbon atom on the cage surface is bonded to three carbon neighbors and it’s bonds are sp2 hybridized with a carbon atom at the vertices of each polygon and a bond along each polygon edge. The Fullerene molecule can undergo a wide range of novel chemical reactions. It readily accepts and donates electrons. A related fullerene molecule, named buckminsterfullerene (C60 fullerene), consists of 60 carbon atoms. Please note – there is no scientific evidence or permits indicating this material is safe for human consumption.
Fullerene 70 was discovered in 1985 by Harold. W. Kroto, Robert F. Curl and Richard E. Smalley at Rice University. Kroto, Curl and Smalley were awarded the 1996 Nobel Prize in Chemistry for their roles in the discovery of cage-like fullerenes. The discovery of fullerene 70 was serendipitous, as the scientists were aiming to produce carbon plasmas to replicate and characterize unidentified interstellar matter. The name is a homage to Buckminster Fuller, whose geodesic domes these molecules resemble. Using laser evaporation of graphite they found Cn clusters (for even n with n > 20) of which the most common were C60 and C70. The carbon fullerenes C70 molecule can undergo a wide range of novel chemical reactions. Carbon Fullerenes C70 are the third allotropic form of carbon material (after graphite and diamond). Fullerenes composed of less than 300 carbon atoms (endohedral fullerenes) are commonly known as “buckyballs”.
The C70 molecule has a D5h symmetry and consist of 20 hexagonal and 12 pentagonal rings as the basis of an icosohedral symmetry closed cage structure with a carbon atom at the vertices of each polygon and a bond along each polygon edge. The C70 molecule has two bond lengths, the 6:6 ring bonds can be considered “double bonds” and are shorter than the 6:5 bonds. Its structure is similar to that of C60 molecule (20 hexagons and 12 pentagons), but has a belt of 5 hexagons inserted at the equator. C70 is not “superaromatic” as it tends to avoid double bonds in the pentagonal rings, resulting in poor electron delocalisation. As a result, C70 behaves like an electron deficient alkenes and reacts readily with electron rich species. The geodesic and electronic bonding factors in the structure account for the stability of the molecule. The molecule has eight bond lengths ranging between 0.137 and 0.146 nm. Each carbon atom in the structure is bonded covalently with 3 others.
Applications of Fullerene C70:
Fullerene C70 are used as organic photovoltaics (OPV).
Fullerene C70 are used in water purification.
Fullerene C70 are used in biohazard protection
Fullerene C70 are used in medicine.
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