Anelastic spectroscopy for studying O vacancies in perovskites

We present the results of anelastic relaxation experiments (2-30 kHz) on ceramic SrTiO3 subjected to reduction in H2 atmosphere, which yield a balance between VO and (OH)− defects. The resulting anelastic spectrum contains, besides the well-known structural transformation near 110 K, several thermally activated relaxation processes between 200 and 700 K. The two main elastic energy loss peaks are proposed to provide the first measurement of the hopping rate of VO -(OH)− defects in pure SrTiO3.