Fullerene C70 is used in optical computing, optical memories,optical signal processing and controlling applications respects; In addition, C70 and its derivatives can be widely used in magnetic resonance imaging, anti-HIV drugs, anti-cancer drugs, chemotherapy drugs, cosmetic additives, research and other areas.
C70 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. A related fullerene molecule, named buckminsterfullerene (C60 fullerene), consists of 60 carbon atoms. It was first intentionally prepared in 1985 by Harold Kroto, James R. Heath, Sean O’Brien, Robert Curl and Richard 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 name is a homage to Buckminster Fuller, whose geodesic domes these molecules resemble.
Solid C70 crystallizes in monoclinic, hexagonal, rhombohedral, and face-centered cubic (fcc) polymorphs at room temperature. The fcc phase is more stable at temperatures above 70 °C. The presence of these phases is rationalized as follows. In a solid, C70 molecules form an fcc arrangement where the overall symmetry depends on their relative orientations. The low-symmetry monoclinic form is observed when molecular rotation is locked by temperature or strain. Partial rotation along one of the symmetry axes of the molecule results in the higher hexagonal or rhombohedral symmetries, which turn into a cubic structure when the molecules start freely rotating. C70 forms brownish crystals with a bandgap of 1.77 eV. It is an n-type semiconductor where conductivity is attributed to oxygen diffusion into the solid from atmosphere. The unit cell of fcc C70 solid contains voids at 4 octahedral and 12 tetrahedral sites. They are large enough to accommodate impurity atoms. When electron-donating elements, such as alkali metals, are doped into these voids, C70 converts into a conductor with conductivity up to around 2 S/cm.
Fullerenes C70 Application: health products; pharmaceutical intermediates; drug delivery applications; energy efficiency; rubber and film modifier; useful electron acceptor; molecules in organic electronics; Because of its excellent characteristics of free radical capture, light absorption, superconducting semiconductor, perfect structure, DNA affinity, high efficiency adsorption, embedded molecular and other characteristics, composite materials; additives..
Post time: Apr-23-2020