Conduction and tritium diffusion studies in single crystals of potassium hydrogen sulfate

Direct-current electrical conductivity of single crystals of KHSO₄ doped with 5, 11, 30, and 437 ppm of cobalt-II is studied in the temperature range 25 to 165°C. The point defect parameters are calculated by graphical analysis of the conductivity data. Various parameters are obtained: enthalpy for the migration of proton (referred to as the enthalpy for the rotation of HSO₄ ion), H_M = 0.55 ± 0.01 eV; the enthalpy for the formation of the intrinsic defects (referred to as the enthalpy for the breaking of the HSO₄ dimers), H_F = 1.30 ± 0.01 eV; and the enthalpy for the impurity-vacancy association H_a = ?0.14 ± 0.01 eV. The tritium diffusion studies in the pure KHSO₄ single crystals give 0.22 ± 0.01 eV and ?1.09 × 10^?3 eV K^?1 as the activation enthalpy and entropy for the process, respectively. The Nernst-Einstein relation is not obeyed. The mechanisms for the conduction and diffusion preocesses in this crystal are discussed.