Electron paramagnetic resonance spectra of X-irradiated samples of the fast proton conductor, Cs5H3(SO4)4•H2O, were determined at temperatures ranging from 80 to 415K. Two types of paramagnetic SO4- center were observed, with differing proton configurations below about 370K. A freeze-out behavior was exhibited by one of them at temperatures below about 200K.

S.Waplak, W.Bednarski, A.I.Baranov, L.A.Shuvalov: Journal of Physics - Condensed Matter, 1997, 9[23], 4813-21