Interplay between atomic and electronic structure in liquid noble–polyvalent metal systems

Abstract The structure of Ag–Ga (Sn, Bi) melts has been investigated using X-ray diffraction. A non-linear behaviour of the structure-sensitive parameters has been observed. As in the case of the crystalline solids there is shown to exist strong interplay between the atomic and electronic structure in the liquid state. As the most prominent effect a maximum of the structure factor occurs at values of the diffraction vector near 2kF (kF – magnitude of Fermi vector) for alloys with a mean valence Z =1.7 –1.8 electrons per atom. For such compositions the peaks of the pair correlation function match with the minima of the Friedel oscillations, which indicates a stability of the atomic arrangement in the melt. The Ag–Ga (Sn, Bi) liquid alloys are assumed to consist of electronically stabilized clusters (Ag65Ga35, Ag75Sn25 and Ag80Bi20 respectively) and clusters of the pure elements (either Ag or polyvalent metal depending on the concentration of the alloy under consideration).