Measurements of thermoelectric power were performed below a superionic transition on Rb3H(SeO4)2. The thermoelectric power S indicated the positive sign above about 350K. This fact indicated that the majority carriers were protons. From this result, it was found that the electrical conduction below the superionic transition (Tc = 449K) was caused by protons. Moreover, from the temperature dependence of S, the activation energy for proton motion below Tc was determined to be 0.45eV.

Evidence for Proton Conduction below Superionic Transition on Rb3H(SeO4)2. Y.Matsuo, K.Takahashi, S.Ikehata: Solid State Communications, 2001, 119[2], 79-81

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