This proposal involves research on the nature of the structure of quasicrystals and metallic glasses that can form quasicrystalline structures upon annealing. Conditions for formation of quasicrytals will be ascertained from analysis of structural relaxation occurring in the amorphous state and subsequent transformation into the quasicrystalline state. Experimental techniques to be applied include differential anomalous X-ray scattering, neutron scattering, energy dispersive X-ray and synchrotron radiation diffraction. Several metallic glass alloy systems will be studied that show tendencies toward possible quasicrystalline structure formation. Dr. Egami has an outstanding research record and the facilities at the University of Pennsylvania are excellent for performing the proposed program. This research was previously supported by NSF Grant DMR-8318816.