Carbon fullerence-based

In 1991, scientists at AT T Bell Laboratories discovered a new class of high-temperature superconductors based on fullerene, the allotrope of carbon that contains Cgo molecules (Sections 10.10 and 19.6). Called "buckyballs," after the architect R. Buckminster Fuller, these soccer ball-shaped Cgo molecules react with potassium to give K3C6o- This stable crystalline solid contains a face-centered cubic array of buckyballs, with K+ ions in the cavities between the Cgo molecules (Figure 21.16). At room temperature, K3Q,o is a metallic conductor, but it becomes a superconductor at 18 K. The rubidium fulleride, Rb C o, and a rubidium— thallium-Cfio compound of unknown stoichiometry have higher Tc values of 30 K and 45M8 K, respectively. 

In the mid-1980s, virtually simultaneous reports on two new precise molecular level constructions of sub-nanoscopic/nanoscopic size appeared in the literature. In 1984 we (DAT) reported the synthesis, isolation and characterization of the first iterated series of Starburst/cascade dendrimers based on genealogical synthesis [2, 77-83]. The following year Smalley, Curl and Kroto described the first observation of a 60-carbon fullerene by mass spectroscopy [43a]. More recently the synthesis of buckminsterfullerene has been achieved by physicists at the Max Planck Institute in Heidelberg [44] to give macroscopic quantities of the third allotropic and first molecular form of carbon, named after Buckminster Fuller. Similarities between these two constructions were not initially apparent, but in retrospect they deserve comment in so far as they each involve molecular level synthesis leading to closed geometrical architecture". 

Carbon Nanotubes, Fullerenes, and Quantum Dots Carbon nanotubes and fuller-enes are carbon-based nanomaterials, and quantum dots are semiconductor nano-... 

Buckminsterfullerene, named after the visionary architect Buckminster Fuller, is just one example of a carbon-based molecule with an intriguing molecular architecture. 

Fullerenes, Fullerides. Molecular structures of atoms arranged on the surface of a sphere or a cylinder, in hexagonal and pentagonal arrays, in configurations similar to R. Buckminster Fuller s geodesic domes. Nanometersized tubes are being developed based on cylindrical Fullerenes. 28 to 540 carbon atoms in such a spherical arrangement form the most symmetric possible molecules - Buckminster Fullerene or Buckyballs . 

For a fuller discussion of black pigments based on bone chars, see carbon-based blacks group cokes sub-group. 

According to the Colour Index (1971), synthetic calcite can be produced industrially in two ways (1) from conversion of calcium oxide, and (2) as a precipitate of calcium chloride with sodium carbonate. The resultant compound was often used as a base for lake pigments and as an extender for others. However, see calcium carbonates group for a fuller discussion of synthesis. The Colour Index designation for this pigment is Cl 77220/Pigment White 18. The term whiting also may refer to a synthetic calcimn carbonate. 

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