C70 fullerene
Names | |
---|---|
Preferred IUPAC name
(C70-D5h(6))[5,6]Fullerene[1] | |
Other names
Fullerene-C70, rugbyballene
| |
Identifiers | |
3D model (
JSmol ) |
|
ChEBI | |
ChemSpider | |
ECHA InfoCard
|
100.162.223 |
PubChem CID
|
|
CompTox Dashboard (EPA)
|
|
| |
| |
Properties | |
C70 | |
Molar mass | 840.770 g·mol−1 |
Appearance | Dark needle-like crystals |
Density | 1.7 g/cm3 |
Melting point | sublimates at ~850 °C[3] |
insoluble in water | |
Band gap | 1.77 eV[2] |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
|
Part of a series of articles on |
Nanomaterials |
---|
Carbon nanotubes |
Fullerenes |
Other nanoparticles |
Nanostructured materials |
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 (or C60 fullerene) consists of 60 carbon atoms.
It was first intentionally prepared in 1985 by
History
Theoretical predictions of buckyball molecules appeared in the late 1960s to early 1970s,[5] but they went largely unnoticed. In the early 1970s, the chemistry of unsaturated carbon configurations was studied by a group at the University of Sussex, led by Harry Kroto and David Walton. In the 1980s a technique was developed by Richard Smalley and Bob Curl at Rice University, Texas to isolate these substances. They used laser vaporization of a suitable target to produce clusters of atoms. Kroto realized that by using a graphite target.[6]
C70 was discovered in 1985 by Robert Curl, Harold Kroto and Richard Smalley. Using
Synthesis
In 1990, K. Fostiropoulos, W. Krätchmer and D. R. Huffman developed a simple and efficient method of producing fullerenes in gram and even kilogram amounts which boosted fullerene research. In this technique, carbon soot is produced from two high-purity graphite electrodes by igniting an arc discharge between them in an inert atmosphere (helium gas). Alternatively, soot is produced by
Properties
Molecule
The C70 molecule has a D5h symmetry and contains 37 faces (25 hexagons and 12 pentagons) with a carbon atom at the vertices of each polygon and a bond along each polygon edge. 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. 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.[8]
C70 can undergo six reversible, one-electron reductions to C6−
70, whereas
), indicating that C70 is an electron acceptor.[9]
Solution
Solvent | S (mg/mL) |
---|---|
1,2-dichlorobenzene | 36.2 |
carbon disulfide | 9.875 |
xylene | 3.985 |
toluene | 1.406 |
benzene | 1.3 |
carbon tetrachloride | 0.121 |
n-hexane | 0.013 |
cyclohexane | 0.08 |
pentane | 0.002 |
octane | 0.042 |
decane | 0.053 |
dodecane | 0.098 |
heptane | 0.047 |
isopropanol
|
0.0021 |
mesitylene | 1.472 |
dichloromethane | 0.080 |
Fullerenes are sparingly soluble in many aromatic solvents such as toluene and others like carbon disulfide, but not in water. Solutions of C70 are a reddish brown. Millimeter-sized crystals of C70 can be grown from solution.[11]
Solid
Solid C70 crystallizes in
All phases of C70 form brownish crystals with a
Symmetry | Space group | No | Pearson symbol |
a (nm) | b (nm) | c (nm) | Z | Density (g/cm3) |
---|---|---|---|---|---|---|---|---|
Monoclinic | P21/m | 11 | mP560 | 1.996 | 1.851 | 1.996 | 8 | |
Hexagonal |
P63/mmc | 194 | hP140 | 1.011 | 1.011 | 1.858 | 2 | 1.70 |
Cubic | Fm3m | 225 | cF280 | 1.496 | 1.496 | 1.496 | 4 | 1.67 |
References
- ISBN 978-0-85404-182-4.
- ^ .
- ISBN 978-0-7923-7174-8. Retrieved 26 December 2011.
- ^ Press Release. Nobel Prize Foundation. 9 October 1996
- ^ a b Katz, 363
- ^ Katz, 368
- ^ Katz, 369–370
- .
- ^ Buckminsterfullerene, C60. University of Bristol. Chm.bris.ac.uk (1996-10-13). Retrieved on 2011-12-25.
- ^ Bezmel'nitsyn, V.N.; Eletskii, A.V.; Okun', M.V. (1998). "Fullerenes in solutions". .
- ^ Talyzin, A.V.; Engström, I. (1998). "C70 in Benzene, Hexane, and Toluene Solutions". .
- ^ hdl:2066/99047.
- .
- ^ Katz, 372
- S2CID 4331074.
Bibliography
- Katz, E. A. (2006). "Fullerene Thin Films as Photovoltaic Material". In Sōga, Tetsuo (ed.). Nanostructured materials for solar energy conversion. Elsevier. pp. 361–443. ISBN 978-0-444-52844-5.