Crystal Structure of BaTiO3 Ultrafine Particles via the Sol-Gel Method
BaTiO3 and BaTiO3:Gd3+ ultrafine particles were prepared by the sol-gel method. 0.1mol% of Ba2+ was substituted by Gd3+ for BaTiO3:Gd3+ powders. Electron spin resonance measurements were carried out for these powders to clarify the crystal structure. The crystallite size of these particles was determined by X-ray diffraction analysis with the aid of Scherrer's equation as well as transmission electron microscopy. The crystallite size of these particles is 25 to 40 nm. The profile of the electron spin resonance spectrum at room temperature for BaTiO3: Gd3+ powder suggests that the phase present in these powder samples possesses an intermediate structure between the tetragonal and cubic phases at room temperature.