Phase transitions in the SrHfO3 perovskite measured with 111In/Cd PAC

P. DE LA PRESA; R. E. ALONSO; A.P. AYALA; V.V. KRISHNAMURTI; K.P. LIEB; A. LÓPEZ GARCÍA; M. NEUBAUER; J. ROTH

HYPERFINE INTERACTIONS

Año: 1998 vol. 120 p. 479 - 483

0304-3843

Electric field gradients in perovskites SrHfO$_3$ and BaHfO$_3$ powder samples have been investigated by means of Perturbed Angular Correlation spectroscopy using implanted $^{111}$Inhyperfine 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 have been established, with the largest fraction showing a pronounced dynamic interaction, and the two other fractions exhibiting very similar quadrupole interaction parameters. We discuss the results in relation to those obtained for $^{111}$In/$^{111}$Cd-impurities in PbZrO$_3$ and BaTiO$_3$ perovskites, and for $^{181}$Hf/$^{181}$Ta-probes in AHfO$_3$ (A = Ca, Sr, Ba).