Neutron-diffraction study of bulk amorphous Al₃₂Ge₆₈ alloy

A neutron-diffraction study was carried out at 100 K on a bulk amorphous Al₃₂Ge₆₈ alloy produced by the thermobaric technique. Fourier transformation of the measured structure factor and reverse Monte Carlo simulations have been performed to obtain a total radial distribution function and three-dimensional atom configurations. It was found that the effective coordination number (n=4.5) is appreciably higher than 4, the characteristic for tetrahedral coordination. The partial atom-atom correlations obtained are analyzed and the results indicate a well-defined covalent bonding between Ge atoms and rather broad distribution for Al-Ge and Al-Al nearest neighbors.