VIBRATIONAL DENSITY-OF-STATES OF DECAGONAL AL70CO15NI15

The generalized vibrational density of states (GVDOS) has been determi ned for decagonal Al70Ni15Co15 using cold neutron inelastic scattering techniques. The GVDOS is compared with a computer simulation using re alistic binary Al-Co pair potentials and the 'tiling-and-decoration' a tomic model based on binary tiling with a rhombus edge length of about 6.4 Angstrom. It is proposed that the computer modelling of the GVDOS using realistic pair potentials might provide valuable information ab out the details of the complex atomic structures such as quasicrystals , which are not easily accessed by diffraction experiments. As a first step in this direction, it is shown that the occupancy of certain 'pr oblematic' atomic positions in the model can be clearly assigned to pa rticular features of the GVDOS.