Ionic Conductivity in Molecular Liquids and Partially Ionized Molten Salts

  • Stuart I. Smedley


Liquids at their 1-atm melting point, that are comprised mostly of uncharged molecules, are regarded as molecular liquids. Their conductivity is low and is believed to arise from the ions produced by the self-ionization of the parent molecules. The ionization constant is generally very sensitive to pressure and temperature, and this is a result of the relatively high compressibilities and expansivities of these liquids compared to ionic melts. The latter arise because of the lack of coulombic cohesive forces. Partially ionized molten salts have conductivities intermediate between those of ionic melts and molecular liquids, reflecting the proportion of dissociated ions to covalent molecules or ion pairs.


Ionic Mobility Coexistence Curve High Compressibility Molecular Liquid Uncharged Molecule 
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  1. 1.
    L. F. Grantham and S. J. Yosim, Negative temperature coefficients of electrical conductance in molten salts, J. Phys. Chem. 45, 1192–1198 (1966).CrossRefGoogle Scholar
  2. 2.
    L. F. Grantham, Electrical conductivities of molten cadmium-cadmium halide solutions, J. Chem. Phys. 44, 1509–1513 (1966).CrossRefGoogle Scholar
  3. 3.
    B. Bardoll and K. Tödheide, Die elektrische Leitfähigkeit und der Dissoziationzustand der geschmolzenen Quecksilberhalogenide bei Drücken bis 6 kbar, Ber Bunsenges Phys. Chem. 79, 490–497 (1975).Google Scholar
  4. 4.
    von G. Treiber and K. Tödheide, Der kontinuierliche Ubergang vom Isolator zum lonenleiter am Beispiel des Wismutchchlorids, Ber Bunsenges Phys. Chem. 77, 541–547 (1973).Google Scholar
  5. 5.
    W. B. Holzapfel, Effect of pressure and temperature on the conductivity and ionic dissociation of water up to 100 kbar and 1000°C, J. Chem. Phys. 50, 4424–4428 (1969).CrossRefGoogle Scholar
  6. 6.
    D. J. Bearcroft and N. H. Nachtrieb, Electrical conductance of salts in liquid iodine; I: Iodide donor solutes, J. Phys. Chem. 71, 316–323 (1967).CrossRefGoogle Scholar
  7. 7.
    B. Cleaver and S. I. Smedley, Pressure dependence of electrical conductivity for fused mercuric halides, Trans. Faraday Soc. 67, 1115–1127 (1971).CrossRefGoogle Scholar
  8. 8.
    A. J. Darnell and W. A. McCollum, Fusion curve and electrical conductivity of molten MgCl2 and HgI2 at elevated pressure, J. Chem. Phys. 55, 116–122 (1971).CrossRefGoogle Scholar
  9. 9.
    J. E. Bannard and G. Treiber, The effect of temperature and pressure on the electrical conductance of molten mercury (II) iodide, High Temperatures-High Pressures 5, 177–182 (1973).Google Scholar
  10. 10.
    B. Cleaver and P. N. Spencer, Isothermal compressibilities and thermal pressure coefficients of molten salts, High Temperatures-High Pressures 7, 539–547 (1975).Google Scholar
  11. 11.
    B. Cleaver, P. N. Spencer, and M. A. Quddus, Effect of pressure on the electrical conductivities of some molten B group metal iodides and iodine, J. Chem. Soc. Faraday I, 3, 686–696 (1978).CrossRefGoogle Scholar
  12. 12.
    B. Cleaver and P. Zani, to be published; see Ref. 27 of Ref. 11.Google Scholar
  13. 13.
    K. Tödheide, in Water, A Comprehensive Treatise (F. Franks, ed.), Vol. 1, Plenum Press, New York (1972), Chapter 13.Google Scholar
  14. 14.
    M. Buback and E. U. Franck, Ionic conductivity of liquid NH4Cl from triple point to critical point, Ber. Bunsenges. Phys. Chem. 77, 1074–1079 (1973).Google Scholar

Copyright information

© Plenum Press, New York 1980

Authors and Affiliations

  • Stuart I. Smedley
    • 1
  1. 1.Victoria University of WellingtonWellingtonNew Zealand

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