Theoretical studies of atomic structure and electronic structure in ternary amorphous Al-Cu-Y and Mg-Cu-Y alloys

The atomic structure for the amorphous Alx(Cu0.4Y0.6)100-x and Mgx(Cu0.4Y0.6)100-x (x = 30 and 80) alloys has been calculated in molecular dynamics simulations with the use of the Hausleitner-Hafner approach for the construction of the interatomic potentials. The parameters are adjusted so as to reconcile the resulting radial distribution function (RDF) spectrum with the measured one as closely as possible. Using the atomic structure thus obtained, the valence band structure is calculated in the LMTO recursion method. We show in this way the development of different chemical bonding states, depending on whether the third element introduced into the amorphous Cu-Y matrix is Al or Mg, and can successfully explain the Al and Mg concentration dependence of various physical properties. (author)