Temperature Dependence Of The Hyperfine Parameters In The SrHfO3 And BaHfO3 Perovskites Measured With 111In/111Cd Probe

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

Durban, S.Africa

Congreso; 11th International Conference on Hyperfine Interactions; 1998

<!-- /* Font Definitions */ @font-face {font-family:"Cambria Math"; panose-1:2 4 5 3 5 4 6 3 2 4; mso-font-charset:0; mso-generic-font-family:roman; mso-font-pitch:variable; mso-font-signature:-1610611985 1107304683 0 0 415 0;} /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-unhide:no; mso-style-qformat:yes; mso-style-parent:""; margin:0in; margin-bottom:.0001pt; mso-pagination:widow-orphan; mso-layout-grid-align:none; punctuation-wrap:simple; text-autospace:none; font-size:12.0pt; mso-bidi-font-size:10.0pt; font-family:"Times New Roman","serif"; mso-fareast-font-family:"Times New Roman"; mso-ansi-language:DE;} .MsoChpDefault {mso-style-type:export-only; mso-default-props:yes; font-size:10.0pt; mso-ansi-font-size:10.0pt; mso-bidi-font-size:10.0pt;} @page Section1 {size:8.5in 11.0in; margin:1.0in 1.0in 1.0in 1.0in; mso-header-margin:.5in; mso-footer-margin:.5in; mso-paper-source:0;} div.Section1 {page:Section1;} --> The temperature dependence of the hyperfine parameters in perovskites SrHfO3 and BaHfO3 powder samples have been investigated by means of Perturbed Angular Correlation spectroscopy using implanted 111In hyperfine probes. The measurements have been performed in the temperature ranges from 22 to 893 K for SrHfO3 and from 293 to 875 K for BaHfO3. 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 and thermal behaviour. We assign the first fraction to 111In/111Cd probe atoms on substitutional Hf sites in both compounds. The temperature dependence of the dynamic interaction has been associated to the Pnma « Imma phase transition for SrHfO3 at ~700 K. We discuss the results in relation to those obtained for 181Hf/111Ta-probes in AHfO3 (A = Ba, Sr, Ca)[1,2,3] and for 111In/111Cd-probes in PbZrO3 and BaTiO3[4].