Study of the electronic properties of a double-chain model for Al-rich-transition-metal quasicrystals, amorphous, and crystalline phases

The electronic properties of quasicrystals containing transition-metals are studied employing a simple double-chain model within the tight-binding approximation. We show that, under determined conditions, spectral fine structures are the result of competing localized- and extended-like states, which are not observed in traditional one-dimensional aperiodic models. These spectral features can explain the experimentally observed transport properties. From this point of view this double-chain model mimics the behavior of electrons in realistic icosahedral quasicrystals. Moreover, in view of the electronic transport, the relationship between quasicrystals and related amorphous phases is explained in a natural way.