Superconduction of metals

The generally accepted theory of electric superconductivity of metals is based upon an assumed interaction between the conduction electrons and phonons in the crystal.1-3 The resonating-valence-bond theory, which is a theoiy of the electronic structure of metals developed about 20 years ago,4-6 provides the basis for a detailed description of the electron-phonon interaction, in relation to the atomic numbers of elements and the composition of alloys, and leads, as described below, to the conclusion that there are two classes of superconductors, crest superconductors and trough superconductors. 

J. R. Waldram, Superconductivity of metals and cuprates, Institute of Physics Publishing, Bristol and Philadelphia, 1996. 

J.R. Waldron, 1996, Superconductivity of Metals and Cuprates, Institute of Physics, Bristol. 

An Introduction to the Theory of Superfluidity, 1965 Superconductivity of Metals and Alloys, 1966 Pseudopotentials in the Theory of Metals, 1966 Phenomenological Theories of High Energy Scattering ... 

The relatively low transition temperatures of the metals shown in Table 18.3 mean that it would be impractical to make superconducting motors or transmission lines from them. Shortly after the superconductivity of metals was discovered, certain alloys (mixtures of metals) were prepared that had much higher transition temperatures than the metals themselves. Niobium alloys showed the most promise, but they still had to be cooled to below 23 K ( —250°G) to exhibit superconductivity. To maintain such a low temperature would require liquid helium, which costs about 6 per liter— an expensive proposition for all but the most exotic applications. 

Table k.2-2 Pressure dependence of the superconductivity of metals [2.1], cont. 

Fullerenes have been reduced in the solid state, using the alkali metals Li, Na, K, Rb and Cs, which have the ability to intercalate in the vapor phase into solid fullerenes [133]. The discovery of the superconductivity of metal intercalated C o [136] attracted much attention to such materials therefore, the metal intercalation of... 

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