Ab initio molecular dynamics study of the static, dynamic, and electronic properties of liquid mercury at room temperature

摘要

We report a study on several static, dynamic, and electronic properties of liquid Hg at room temperature. We have performed ab initio molecular dynamics simulations using Kohn–Sham density functional theory combined with a nonlocal ultrasoft pseudopotential. The calculated static structure shows good agreement with the available experimental data. We present results for the single-particle dynamics, and recent experimental data are analyzed. The calculated dynamic structure factors Sq, fairly agree with their experimental counterparts as measured by inelastic x-ray and neutron scattering experiments. The dispersion relation exhibits a positive dispersion, which however is not so marked as suggested by the experiment; moreover, its slope at the long-wavelength limit provides a good estimate of the experimental sound velocity. We have also analyzed the dynamical processes behind the Sq, in terms of a model including a relaxation mechanism with both fast and slow characteristic time scales.