First-principles molecular-dynamics simulation of expanded liquid rubidium: Temperature dependence of electronic properties

The electronic properties of expanded liquid rubidium are studied at 350 K, near the triple point, and at 1400 K by first-principles molecular-dynamics (MD) simulation. Near the triple point, there is no significant deviation in the electronic density of states of the liquid phase from that of the solid phase while, at higher temperature, a deviation arises from the effects of decreasing density and of the random potential due to large fluctuations in the atomic configuration. The electrical conductivity is calculated by the Kubo-Greenwood formula. The fact that the dc conductivity at 350 K is much larger than that at 1400 K, with values that are in reasonable agreement with the experimental ones, is successfully reproduced.