The generalised vibrational density of states of the metallic glass Fe40Ni40B20 determined by neutron inelastic scattering

The generalised vibrational density of states G( omega ) has been derived from inelastic neutron scattering measurements for the ternary transition metal-metalloid metallic glass Fe40Ni40B20. Two main energy bands are observed centred around 24 and 63 meV and separated by a shallow pseudo-gap near 50 MeV. The former band is mainly due to transition metal-transition metal interaction, the latter is associated to localised optical modes involving transition metal-boron bonds. Rather small differences, if any at all, have been observed for samples prepared by the metal spinning technique at different velocities of the rotating wheel. The neutron weighted G( omega ) have been used to calculate thermodynamic quantities like the temperature dependence of the specific heat and of the Debye temperature.