fullerene seminar_2 (1).pptx
- 2. Name: carbon. Symbol: C. Atomic number: 6. Atomic weight: 12.0107 (8) g r. Group in periodic table: 14. Color: graphite is black, diamond is colorless. Electronic ground state: 1s22s22p2
- 3. ISOTOPES C12 (99% of the naturally occurring carbon -reference for relative atomic mass of 12), C13 (has magnetic moment, spin=1/2 – used as a probe in NMR), C14 (radioactive isotope, half life 5730 years )
- 6. . ALLOTROPES Allotropes Different forms of a chemical element Allotropy is the property of some chemical elements to exist in two or more different forms, or allotropes, when found in nature. There are several allotropes of carbon.
- 7. Allotropes of Carbon a) Diamond, b) Graphite, c) Lonsdaleite, d) C60 (Buckminsterfullerene or buckyball), e) C540, f) C70, g) Amorphous carbon, and h) single-walled carbon nanotube, or buckytube.
- 8. What is a Fullerene? The third allotropic form of carbon material (after graphite and diamond). From left to right: Diamond, graphite, and fullerene. A geodesic dome shares the same geometric structure as a buckminsterfullerene.
- 9. FULLERENE The carbon c60 molecule has been named as fullerene. Buckminster fuller, who designed the structure of c60. A fullerene is any molecule composed entirely of carbon. It is in the form of a hollow sphere, ellipsoid . Spherical fullerenes are also called buckyballs.
- 10. STRUCTURE OF FULLERENE MOLECULE
- 11. It has 12 pentagonal(5sides) and 20 hexagonal(6 sides) faces symmetrically arrayed to form a molecular ball. In fact a soccer ball has the geometric structure configuration if fullerene. The ball-like molecules bind with each other in the solid state to from a crystal lattice having a face centered cubic structure.
- 12. C60 molecule separated from its nearest neighbor by 1nm, and they are held together by weak forces are called vender waals forces. C60 soluble in benzene, single crystals of it can be grown by slow evaporation from benzene solutions. 1nm
- 13. OTHER FULLERENES Larger fullerene such as C70, C76, C80 and C84 have also found. One interesting aspect of the existence of these smaller fullerenes is the prediction that they could be superconductors at high temperature when appropriately doped.
- 14. C60 C70
- 15. C76 C78 The different fullerenes obey to the Euler theorem