Approach to metallic behavior in metal–molten-salt solutions

Abstract

A combined molecular-dynamics density-functional simulation of concentrated ${\mathrm{K}}_{\mathrm{x}}$(KCl${)}_{1\mathrm{-}\mathrm{x}}$ solutions with x≤0.11 has been performed. Bipolaronic structures where two spin-paired electrons are trapped in the same liquid cavity are seen to be a characteristic feature of this mixture. The bipolarons exhibit a tendency to clustering. At x≊0.11 the bipolaronic clusters tend to have an elongated percolating structure which leads to metallic behavior. Our findings are in good agreement with available experimental information.