2001 Volume 42 Issue 6 Pages 911-919
The majority of stable quasicrystals known so far is based upon aluminum. It turns out that the valence band of aluminum atoms in such quasicrystals, as well as in the crystals that exhibit a similar icosahedral short range order, shows a pronounced pseudo-gap located at the position of the Fermi energy. In the present paper, we describe how this specific feature of quasicrystals is uncovered and quantified using spectroscopy techniques. We show then that the pseudo-gap, which persists up to the surface, plays an important role in the thermodynamic stability of these non-conventional materials and is involved in transport properties as well as in surface properties of aperiodic intermetallics.