The effect of cation substitution on the crystal and electronic structures of ferroelectric bismuth titanate has been systematically investigated. According to the x-ray diffraction analyses on Bi3.25A 0.75Ti3O12 (A = Bi, La, Gd, and Y), it was found that the cation substitution gives rise to the contraction of the volume of the unit cell and to the decrease of the structural distortion of the bismuth titanate, as well. The present x-ray absorption spectroscopic results reveal that the local structural change upon chemical reduction is remarkably depressed by the cation substitution through the enhancement of (Ti - O) bonds. Such a stabilization of TiO6 octahedra can be understood by a competition between adjacent (Bi - O) and (Ti - O) bonds as well as the contraction of the unit cell.
Bibliographical noteFunding Information:
This work was supported by Grant No. R08-2003-000-10409-0 from the Basic Research Program of the Korea Science and Engineering Foundation. The experiments at PLS were supported in part by MOST and POSTECH.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy (miscellaneous)