Metal-Nonmetal Transition in Dense Mercury Vapor

Abstract

This article presents the results of conductivity and density measurements of liquid, gaseous, and supercritical mercury up to 1700\ifmmode^\circ\else\textdegree\fi{}C and 2100 bar. Beyond the critical temperature of 1490\ifmmode^\circ\else\textdegree\fi{}C the conductivity varies continuously from ${10}^{\ensuremath{-}4}$ to ${10}^{2}$ ${\mathrm{\ensuremath{\Omega}}}^{\ensuremath{-}1}$ ${\mathrm{cm}}^{\ensuremath{-}1}$ if the density is increased from 2 to 6 g/${\mathrm{cm}}^{3}$. This variation is an example of nonmetal-metal transition and is discussed accordingly. The activation energy of conductivity in the supercritical fluid decreases markedly with increasing density and approaches very small values around 5 g/${\mathrm{cm}}^{3}$. Conductivity data for dense gaseous mercurycesium mixtures are given.