Density Functional Theory for a Model of Non-Uniform Liquid Metal in Partially Ionized States

摘要

The problem of the electronic, ionic and atomic density profiles in a non-uniform liquid metal which can locally exist in partially ionized states is examined using the density functional formalism. Ions and electrons are allowed to bind into atoms through a ''reaction'' governed by the mass action law. Formally exact equations for the density profiles are given in terms of the inverse response matrix of the non-uniform system, which consists of two terms: the first corresponding to a mixture of ions, electrons and structureless atoms and the other to the atomic internal degrees of freedom. Approximate schemes are proposed for both contributions, stressing in particular (i) how ionization of the atoms arises with increasing density and the relation with Mott's criterion for the metal-insulator transition, and (ii) the usefulness of a weak coupling assumption for interspecies correlations. This formalism used together with properly parametrized trial functions for the density profiles should be particularly useful for studying the liquid-vapour interface of alkali metals. 37 refs. (Atomindex citation 17:063535)