Structure of expanded fluid Rb and Cs: a quantum molecular dynamics study

We have performed quantum molecular dynamics simulations for expanded fluid Rb and Cs. We compare the pair correlation functions with results derived from neutron and x-ray scattering experiments. The experimentally observed structural changes with the density and temperature variation are reproduced. The density of states and the electronic charge density extracted from the simulations indicate a crossover from metallic to nonmetallic behaviour near the critical point due to a localization of electrons at nuclei