Dynamic structure factor of liquid Ga close to the melting point: spectral linewidth at high momentum transfer

By simulating an interatomic pair potential obtained from the first-principles generalized energy-independent nonlocal model-pseudopotential (GEINMP) theory, we have reproduced the high-wavevector shoulder in the static structure factor and the recently observed anomaly in the linewidth of the dynamic structure factor of liquid Ga close to the melting point. Our results indicate that the two anomalies have the same physical origin, which is associated with the Friedel oscillations induced by conduction electrons. The anomaly in the dynamics can be well described by the revised Enskog theory for the hardsphere (HS) system, with the effective HS diameter determined by the position at the first peak of the radial distribution function. We interpret the occurrence of the anomaly in the dynamics by the physical picture of cage diffusion. (Some figures in this article are in colour only in the electronic version)