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This work was supported by the Russian Foundation for Basic Research, project no. 10-03-96043-r_Urals_a. Temperature dependencies of density (by the gamma-penetrating method), electrical resistivity (by the contact-less method in rotating magnetic field), and magnetic susceptibility (by the Faraday method) of Sn-Bi alloys with near-eutectic compositions are investigated. The alloy with eutectic composition, Sn -58% (mass) Bi, is shown to differ significantly in the electron structure from hypo- and hypereutectic ones. The melt overheating above the given temperature provides the hysteresis of the properties sensitive to electron structure.

This study was supported by the Russian Foundation for Basic Research (project no. 10-02-00602-a). The heat capacity of icosahedral quasicrystals Al63Cu25Fe12 and Al62Cu25.5Fe12.5 has been studied at high temperatures up to 1700 K, which is by almost 400 K higher than the melting point of the material. It has been shown that the melt exhibits an excess heat capacity with respect to that determined by the Dulong-Petit law and that is a direct extension of the excess heat capacity of the solid state. It has been concluded that the excess heat capacity is related, as a whole, to the short-range order in the quasicrystal structure. This circumstance allows the identification of the orbital hybridization as the most probable mechanism of formation of the pseudogap in the electronic structure of the quasicrystals.

This study was supported by the Russian Foundation for Basic Research (grant no. 07-02-01049). Results are given of an investigation of magnetic susceptibility, electrical resistance, and density of Al62Cu25.5 5Fe(12.5) alloy in the solid and liquid states. It is found that the behavior of the investigated properties at temperatures above the melting point is abnormal. The results are discussed assuming the existence of long-lived (metastable) microregions in the melts.

This work was supported by the Russian Foundation for Basic Research, project no. 10-02-00602-a. The electric resistance, magnetic susceptibility, and specific heat of the icosahedral phases of the Al-Cu-Fe system have been examined in the melt region. It has been shown that the features of the properties of a homogeneous solid state, as well as correlations between these features, hold in melts up to temperatures above the melting point by several hundreds of degrees. The results indicate that the short-range order and orbital hybridization determine the mechanism responsible for the electronic spectrum and ultrahigh-resistance state of quasicrystals.