Conduction in Crystals Containing Hydrogen Bonds. I. KHF2 and KDF2

Direct current electrolysis measurements on solid KHF2 have shown that protons are mobile in the solid, and are liberated as hydrogen gas at the cathode. From the amount of gas evolved it has been concluded that all the current in the solid is carried by the protons. Alternating current conduction measurements have also been made on solid KHF2 and KDF2 at various temperatures. It has been found that in the α-phase region (below 196°C) the conduction follows an Arrhenius-type equation with an activation energy, E=21.7 kcal mole−1, and 23.5 kcal mole−1 for KHF2 and KDF2, respectively. A sharp discontinuity is observed in the conduction plots at the α—β transition, above which an Arrhenius relation is again obeyed with E=19.8 kcal mole−1 and 20.9 kcal mole−1 for KHF2 and KDF2. The suggested mechanism of conduction through the crystal is by migration of interstitial protons or ``proton defects,'' and it is suggested that the observed activation energies refer to the formation of these defects.