EXTENDED X-RAY-ABSORPTION FINE-STRUCTURE DETERMINATION OF LOCAL-STRUCTURE IN SOL-GEL-DERIVED LEAD TITANATE, LEAD ZIRCONATE, AND LEAD-ZIRCONATE-TITANATE

We report on extended x-ray absorption fine structure (EXAFS) measurem ents for partially heat-treated gels in the lead zirconate titanate sy stem (PZT). Self-consistent results obtained from the titanium and zir conium K-edges and the lead LIII-edge were used to determine bonding p athways between cations. For lead titantate (PT) and PZT gels, separat e networks of predominantly Ti-O-Ti, Zr-O-Zr, and Pb-O-Pb linkages wer e observed. For lead zirconate (PZ) gels, both Zr-O-Pb and Zr-O-Zr lin kages were observed. The results indicate heterogeneity at the molecul ar level. These findings are discussed in terms of the evolution of st ructure for PZT materials prepared by our sol-gel method.