Interplay of the atomic and electronic structure in liquid and amorphous AlGe alloys

It is well known that in simple disordered metallic systems maxima of the structure factor, S( q), are related to minima in the electronic density of states (DOS). Photoelectron spectroscopy measurements of liquid Al 75Ge 25, liquid Al 65Ge 35, and amorphous Al 68Ge 32 are presented, showing a lowering of the DOS at the Fermi energy in comparison to the pure liquid alloy constituents. The depression is large in the amorphous and small in the liquid state, where it vanishes with increasing temperature. This feature is explained as being induced by the atomic structure. The temperature dependence of the structure-induced depression of the DOS is a consequence of the temperature dependence of the structure factor itself.