ELECTRONIC DISTRIBUTIONS OF STATES IN CRYSTALLINE AND QUASI-CRYSTALLINE AL-CU-FE AND AL-CU-FE-CR ALLOYS

Valence and conduction state distributions in a series of Al-Cu-Fe and Al-Cu-Fe-Cr alloys of different structural states and nominal compositions have been investigated by means of soft-x-ray emission and photoabsorption spectroscopies. A complete description of the valence band is obtained. The DOS at E(F) is observed to be very low which is consistent with the high resistivity values found for the icosahedral quasicrystalline phase. The existence of a wide pseudo-gap at E(F) is evidenced, which is higher in the quasicrystal than in the related crystalline counterparts.