CONDUCTIVITY OF TETRAMETHYLAMMONIUM FLUORIDE TETRAHYDRATE

The conductivity of tetramethylammonium fluoride tetrahydrate (TMAF4) has been studied by impedance spectroscopy in the temperature range 21 3-322 K. The response of the cell Au \TMAF4\ Au is typical for a polyc rystalline electrolyte between solid blocking electrodes and it is tem perature dependent. A conductivity drop of about two orders of magnitu de is observed at temperatures around the melting point of TMAF4. Line ar Arrhenius-type conductivity dependence is observed for the temperat ure ranges corresponding to the high and low temperature phases of sol id TMAF4. The corresponding activation energies of conductivity are eq ual to 1.93 eV and 0.48 eV. The conductivity of TMAF4 is substantially lower than that of tetramethylammonium hydroxide pentahydrate (TMAOH5 ). However, TMAF4 can also be used in electrochemical studies. The rea sons for the difference in conductivity between TMAF4 and TMAOH5 are d iscussed in terms of their crystallographic structures.