Static structure, microscopic dynamics and electronic properties of the liquid Bi–Li alloy. An ab initio molecular dynamics study

Abstract

We report an ab initio molecular dynamics study of the static, dynamic and electronic properties of the liquid BixLi1−x alloy, which is a complex binary system with a marked tendency to heterocoordination. The calculated total static structure factors are in good agreement with the available experimental data. The partial dynamic structure factors exhibit side peaks indicative of propagating density fluctuations, and for some concentrations we have found a density fluctuation mode with phase velocity greater than the hydrodynamic sound velocity. We have also evaluated other dynamical properties such as the diffusion coefficients, the shear viscosity and the adiabatic sound velocity. The electronic density of states show that the liquid BixLi1−x alloy has a metallic character, although with strong deviations from the free-electron parabolic curve. The results reported improve the understanding of binary liquid alloys with both fast and slow propagating collective modes.