ELECTRONIC-PROPERTIES OF QUASI-CRYSTALS

We present and analyze briefly partial valence and conduction band states distributions of Al6Mn and both crystalline and quasicrystalline AlCuFe phases of dose nominal composition. Low densities of states and a pseudogap are found at the Fermi energy. We discuss the formation of this pseudo-gap as due to the diffraction of electronic conduction states by Bragg planes and emphasize its consequences for the densities of d states of the transition element. We discuss also briefly the transport properties of some systems like AlCuFe which show the proximity of a metal-insulator transition.