Hyperfine interactions in the perovskites SrHfO3 and BaHfO3 observed with 111In/111Cd perturbed angular correlations

Abstract The electric field gradients in perovskite SrHfO 3 and BaHfO 3 powder samples were investigated by means of Perturbed Angular Correlation spectroscopy, using implanted 111 In hyperfine probes. The measurements cover the temperature ranges from 22 to 893 K for SrHfO 3 and from 293 to 875 K for BaHfO 3 , respectively. In both compounds, three quadrupole interactions were established. The largest fraction showing a pronounced dynamic interaction is assigned to 111 In/ 111 Cd probe atoms on substitutional Hf sites in both compounds. For SrHfO 3 , the temperature dependence of the dynamic interaction was associated to the Pnma↔Imma phase transition for SrHfO 3 at about 700 K. We discuss the results in relation to those obtained for 111 In/ 111 Cd-probes in PbZrO 3 and BaTiO 3 , and for 181 Hf/ 181 Ta-probes in AHfO 3 (A=Ca, Sr, Ba).