Temperature dependence of electric field gradients in BaTiO3 - BaHfO3 system

R. E. ALONSO; A.P. AYALA; P. DE LA PRESA; A. LÓPEZ GARCÍA

Seoul, Korea

Congreso; The Ninth International Meeting on Ferroelectricity; 1997

<!-- /* 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:10.0pt; font-family:"Times New Roman","serif"; mso-fareast-font-family:"Times New Roman"; mso-ansi-language:ES-TRAD;} .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;} --> In ferroelectric ABO3 perovskites the substitution of B cation by another one of the same chemical group can strongly alter its electric properties. In this contribution we report the results of a systematic study of BaTi(1-x)HfxO3 solid solutions in the paraelectric phase with x= 0.95, 0.90, 0.70. 0.50 and 0.3. Samples were prepared by firing  mixtures of the corresponding oxides at 1300K and characterized by XRD analysis. We have measured the hyperfine interactions at 181Ta in B sites as a function of temperature for each concentration. The electric quadrupole interaction measured in these materials reflects the distortion of the electron distribution around probes. These results are analyzed in terms of hafnium concentration.