Direct measurements and ab initio simulations for expanded fluid aluminum in the metal-nonmetal transition range

Jean Clérouin, Pierre Noiret, Victor N. Korobenko, and Anatoly D. Rakhel

Phys. Rev. B 78, 224203 – Published 15 December 2008

Abstract

We have performed direct measurements and quantum molecular-dynamics simulations for expanded aluminum at densities two to nine times lower than the normal solid density and internal energies ranging from 7 to 70 kJ/g. The simulation results were found to be in good agreement with the experimental data and reproduce well the main trends observed in the measured dependencies of the electrical resistivity and pressure versus internal energy along isochores. A systematic study of the optical conductivity spectra, one-particle density of states, and the distributions of the electronic charge over supercell shows that the transition of expanded aluminum to a nonmetallic state takes place close to the density at which the constant volume derivative of the electrical resistivity on internal energy becomes negative.