Abstract
Analyses of pyrochlore-and fluorite-type oxide ion conductors Zr2Gd2O7 were made by means of X-ray diffraction, Raman spectroscopy and EXAFS method. Sharp fundamental and diffuse superstructure reflections of the pyrochlore-type phase are interpreted by assuming that anti-phase domain boundaries lie parallel to the {112} . Raman spectrum of the fluorite-type Zr2Gd2O7 was very similar to that of the pyrochlore-type one, which implies that the coordination states of the former are close to those of the latter. At 500°C, formation of Frenkel-type defects was observed in the pyrochlore-type Zr2Gd2O7.
