Stability in ordered and amorphous transition-metal compounds

Abstract

We present a comparison of measured and calculated state densities which suggest (1) that transition-metal glasses possess a short-range coordination similar to that of fcc crystals, (2) that the relative stability of different short-range atomic arrangements varies inversely with the state density at the Fermi level, (3) that transition-metal glasses tend to have large Fermi-level state densities, and therefore (4) that transition-metal glasses are characterized by the relative instability of their short-range atomic arrangements. We also argue that stoichiometry fluctuations are more effective in stabilizing the glass if the valence difference between the constituents is large. This effect is manifest in a correlation between the valence difference of the glass constituents and the width of the concentration range in which glasses form and the relative quenching rates required to form the glasses.