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) measurements for partially heat-treated gels in the lead zirconate titanate system (PZT). Self-consistent results obtained from the titanium and zirconium K-edges and the lead LIII-edge were used to determine bonding pathways between cations. For lead titantate (PT) and PZT gels, separate networks of predominantly Ti-O-Ti, Zr-O-Zr, and Pb-O-Pb linkages were observed. For lead zirconate (PZ) gels, both Zr-O-Pb and Zr-O-Zr linkages were observed. The results indicate heterogeneity at the molecular level. These findings are discussed in terms of the evolution of structure for PZT materials prepared by our sol-gel method.