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Superconductors, fullerene

Thus far the importance of carbon cluster chemistry has been in the discovery of new knowl edge Many scientists feel that the earliest industrial applications of the fullerenes will be based on their novel electrical properties Buckminsterfullerene is an insulator but has a high electron affinity and is a superconductor in its reduced form Nanotubes have aroused a great deal of interest for their electrical properties and as potential sources of carbon fibers of great strength... [Pg.437]

A further indication of the rapid advances that have occurred in the chemistry of the elements during the past 15 years can be gauged from the several completely new sections which have been added to review work in what were previously both nonexistent and unsuspected areas. These include (a) coordination compounds of dihapto-dihydrogen, (b) the fullerenes and their many derivatives, (c) the metcars, and (d) high-temperature oxide superconductors. [Pg.1361]

Williams JM, Ferraro JR, Thom RJ, Carlson KD, Geiser U, Wang HH, Kini AM, Whangbo MH (1992) Organic superconductors (including fullerenes). Prentice Hall, Englewood Cliffs, New Jersey... [Pg.32]

In contrast to carbon, which forms structures derived from both sp2 and sp3 bonds, silicon is unable to form sp2 related structures. Since one out of four sp3 bonds of a given atom is pointing out of the cage, the most stable fullerene-like structure in this case is a network of connected cages. This kind of network is realized in alkali metal doped silicon clathrate (19), which were identified to have a connected fullerene-like structure (20). In these compounds, Si polyhe-dra of 12 five-fold rings and 2 or 4 more six-fold rings share faces, and form a network of hollow cage structures, which can accommodate endohedral metal atoms. Recently, the clathrate compound (Na,Ba), has been synthesized and demonstrated a transition into a superconductor at 4 K (21). The electronic structure of these compounds is drastically different from that of sp3 Si solid (22). [Pg.274]

Since alkali metal doped fullerenes are conductors, and low-temperature superconductors, one wonders if the curved polynuclear hydrocarbons might exhibit a similar behavior. [Pg.3]

Chen CC, Lieber CM (1992) Synthesis of pure Cgo and determination of the isotope effect for fullerene superconductors. J Am Chem Soc 114 3141-3142... [Pg.123]

With the availability of a method to produce fullerenes in the laboratory, the topic has become the rage of the day. It has created great excitement in the scientific world comparable only to that of high-temperature superconductors in early 1987. Cgg and C70 have been characterized in terms of the crystal structure, UV-visible, NMR,... [Pg.58]

The first edition of this textbook was widely praised. In this new edition the authors have taken the opportunity to bring the work completely up to date by the addition of new material on mesoporous materials, fullerenes, molecular magnets, organic conductors and high-temperature superconductors. All of the chapters have been revised with new additional sections. [Pg.550]

In this edition, we have incorporated new material in all the chapters and updated references to the literature. New sections dealing with porous solids, fullerenes and related materials, metal nitrides, metal tellurides, molecular magnets and other organic materials have been added. Under preparative strategies, we have included new types of synthesis reported in the literature, specially those based on soft chemistry routes. We have a new section covering typical results from empirical theory and electron spectroscopy. There is a major section dealing with high-temperature oxide superconductors. We hope that this edition of the book will prove to be a useful text and reference work for all those interested in solid state chemistry and materials science. [Pg.562]

As mentioned in Section 6.3, band waggoning in the early 1990s resulted in several proposals for uses of fullerene [30a] which until now have not reached fruition. High-temperature fullerene superconductors and a C60F60 lubricant illustrate the point. The latter, ball shaped perfluorinated hydrocarbon, should have revolutionized industry by minimizing friction losses of energy. The compound was synthesized. However, it proved unstable. Moreover, it... [Pg.228]

Graphite and diamond are network solids that are insoluble in all liquid solvents except some liquid metals. Flowever, the fullerenes, which are molecular, can be dissolved by suitable solvents (such as benzene) buckminsterfullerene itself forms a red-brown solution. Fullerite currently has few uses, but some of the compounds of the fullerenes have great promise. For example, K3C60 is a superconductor below 18 K, and other compounds appear to be active against cancer and diseases such as AIDS. [Pg.831]

Fullerene, black and shiny like graphite, is the subject of active current research because of its interesting electronic properties. When allowed to react with rubidium metal, a superconducting material called rubidium fulleride, Rb3C6o, is formed. (We ll discuss superconductors in more detail in Section 21.6.) Carbon nanotubes are being studied for use as fibers in the structural composites used to make golf clubs, bicycle frames, boats, and airplanes. On a mass basis, nanotubes are up to ten times as strong as steel. [Pg.412]

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. [Pg.932]

Compare the structure and properties of ceramic superconductors such as YBa2Cu307 with those of fullerene-based superconductors such as Rb3Cg0-... [Pg.944]

J. M. Williams, J. R. Ferraro, R. J. Thom, K. D. Carlson, U. Geiser, H. H. Wang, A. M. Kini, and M.-H. Whangbo, Organic Superconductors (Including Fullerenes) Synthesis, Structure, Properties, and Theory, Prentice Hall, Englewood Cliffs, NJ, 1992. [Pg.816]


See other pages where Superconductors, fullerene is mentioned: [Pg.781]    [Pg.781]    [Pg.2422]    [Pg.36]    [Pg.347]    [Pg.727]    [Pg.27]    [Pg.57]    [Pg.907]    [Pg.2]    [Pg.496]    [Pg.135]    [Pg.345]    [Pg.495]    [Pg.112]    [Pg.458]    [Pg.203]    [Pg.289]    [Pg.345]    [Pg.132]    [Pg.960]    [Pg.14]    [Pg.182]    [Pg.135]    [Pg.36]    [Pg.3]    [Pg.792]    [Pg.432]    [Pg.243]    [Pg.471]    [Pg.471]    [Pg.19]   
See also in sourсe #XX -- [ Pg.447 ]




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