EXPERIMENTAL STUDIES OF ATOMIC-STRUCTURE, ELECTRONIC-STRUCTURE, AND THE ELECTRONIC TRANSPORT MECHANISM IN AMORPHOUS AL-CU-Y AND MG-CU-Y TERNARY ALLOYS

The local atomic structure in the amorphous Al-x(Cu0.4Y0.6)(100-x) and M(x)(Cu0.4Y0.6)(100-x) (0 less than or equal to x less than or equal to 85) alloys was determined by neutron-diffraction experiments. The e lectronic structure near the Fermi level was deter mined using the sam e samples by means of a-ray photoemission spectroscopy and soft x-ray spectroscopy. Both set, of data are combined to determine self-consist ently and uniquely the local atomic structure in both Al- and Mg-based amorphous alloys. The bonding nature and resulting atomic environment are found to depend significantly on whether the third element is AI or Mg. Based on the atomic and electronic structures thus derived, we could interpret the Al or Mg concentration dependence of the crystalli zation temperature, electronic specific-hear coefficient, and also tha t of the resistivity value of 300 K. The origin of the appearance of a positive Hall coefficient observed in the Al-based amorphous alloys b ut not in the Mg-based amorphous alloys is also briefly discussed.