Proton dynamics in phase I of CsHSO4 were studied by means of 1H spin-lattice relaxation. From the analysis of the relaxation times, mean residence times of protons were estimated. Translational diffusion of protons takes place with parameters of 35kJ/mol and 1.7 x 10−13s. The proton mean residence time changed from 3.0 x 10−9 to 1.3 x 10−9s between 430 and 470K. These parameters could well explain the macroscopic electric conductivity. The proton transfer between two SO4 tetrahedra along a H bond was fast enough and the proton transport was limited by the SO4 reorientation in a similar manner to phase II.

Proton Diffusion in the Superprotonic Phase of CsHSO4 Studied by 1H NMR Relaxation. S.Hayashi, M.Mizuno: Solid State Ionics, 2004, 171[3-4], 289-93