Local structure analysis of BaTiO nanoparticles

Yoneda, Yasuhiro   ; Kohara, Shinji*; Kato, Kazumi*

The atomic-scale structure of nanocrystalline BaTiO powders has been studied using high-energy X-ray diffraction, X-ray absorption fine structure, and the atomic pair-distribution function technique. The studies show that the materials are well-ordered at nanometer length distance. The three-dimensional atomic ordering in BaTiO is cubic-like on average, but locally shows slight distortions of a tetragonal-type, similar to that occurring in the coarsegrained bulk crystals. Ferroelectric coherence is facilitated in part by control of particle morphology. The spatial extent of cooperative ferroelectric distortions is found to be degraded in nanometer-sized building blocks.