On singularities of electronic state density in liquid metals and disordered metallic alloys

Abstract

We have performed a qualitative consideration of the problem of structurally dependent singularities of the density of electronic states,N(E), in disordered metallic systems: liquids, glasses and alloys. The appearance of Kohn anomalies atq 0≅2K F (q 0 being the maximum position of the structure factorS(q);K F , the Fermi momentum) in thermodynamic properties of liquid and amorphous metals is analyzed. It has been shown that the appearance of these contributions is due to the presence of a diffuse (inelastic) part ofS(q) and that they are no analogs of the Van Hove singularities (VHS) in crystals. The corollary of the hypothesis about the “quasicrystalline” structure of liquids, i.e. the appearance of “blurred” VHS's inN(E), is treated. A strict solution of the problem of the “Gaussian” static disorder effect on the VHS in crystalline alloys is presented. A new energy scale in the relaxation time and, consequently, in kinetic coefficients has been revealed.