Electrical Conductivity of Molten Mercuric–Mercurous Halide Systems

Abstract

The electrical conductivities of the molten HgCl₂–Hg₂Cl₂ system and the molten HgI₂–Hg₂I₂ system were measured from the liquidus temperature to approximately 600°C. In both systems the electrical conductivity increased orders of magnitude as the composition of Hg₂X₂ was increased. The initial “activation energy” for conduction decreased in the chloride system and increased in the iodide system as the concentration of Hg₂X₂ was increased. In contrast to the BiX₃–BiX systems where semiconduction was found above 400°C, the results of this study suggest that little or no semiconduction occurs in these systems and that the conductivity increase is due to the dissolution of a conducting salt (Hg₂X₂) in a nonconducting solvent (HgX₂).