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Nested closed fullerenes have been named bucky onions. Cylindrical fullerenes are also called carbon nanotubes or buckytubes. [1] The bulk solid form of pure or mixed fullerenes is called fullerite. [2] Fullerenes had been predicted for some time, but only after their accidental synthesis in 1985 were they detected in nature [3] [4] and outer ...
They can be synthesized by incorporating fullerenes onto the ends of polymerized chains or growth of a polymeric chain from a functionalized fullerene derivative and additionally closure. Introducing fullerene spheres into the end of the macromolecule significantly increases hydrophobicity of the original polymer.
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.
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 ...
These endohedral fullerenes are usually synthesized by doping in the metal atoms in an arc reactor or by laser evaporation. These methods gives low yields of endohedral fullerenes, and a better method involves the opening of the cage, packing in the atoms or molecules, and closing the opening using certain organic reactions. This method ...
Lonsdaleite is an allotrope sometimes called "hexagonal diamond", formed from graphite present in meteorites upon their impact on the earth. The great heat and pressure of the impact transforms the graphite into a denser form similar to diamond but retaining graphite's hexagonal crystal lattice. "Hexagonal diamond" has also been synthesized in ...
The carbon cycle is a biogeochemical cycle that is important in maintaining life on Earth over a long time span. The cycle includes carbon sequestration and carbon sinks. [4] [5] Plate tectonics are needed for life over a long time span, and carbon-based life is important in the plate tectonics process. [6]
Over two-thirds of mineral species owe their existence to life, [12] but life may also owe its existence to minerals. They may have been needed as templates to bring organic molecules together; as catalysts for chemical reactions; and as metabolites. [1] Two prominent theories for the origin of life involve clays and transition metal sulfides.