John P. Hernandez Department of Physics and Astronomy, University of North Carolina -- Chapel Hill
4 PM, Thursday, September 28, 1995
Room 101, Olin Physical Laboratory
The intimate relationship between the liquid-vapor and metal-nonmetal transitions of the alkali fluids, explored experimentally in the last fifteen years, have posed a challenge to theoretical understanding. In a collaboration with P. Tarazona and E. Chacon (Madrid, Spain), we have investigated a series of simple models to deduce the microscopic aspects required in order that calculations will reflect the observed structural, thermodynamic, and electronic properties of such fluids. A self-consistent treatment of the disordered ionic structure and the valence electron distribution is the key to understanding these materials. Monte Carlo simulations have been used to determine the equilibrium ionic structures, in lattice-gas and continuous models, coupled with an energy per ion determined by the local environments. Electron delocalization effects are of crucial importance. Electronic properties are determined by the structural ones. An overview of our ongoing theoretical studies, and comparison of our results with experiments, will be given and related to our published work {Phys.Rev. Lett. 74, 142 (1995); Phys. Rev. B 52 (1995), Oct. 1}.