Bonding and electronic structure in zirconia pseudopolymorphs investigated by electron energy-loss spectroscopy

The use of electron energy-loss spectroscopy for characterization of zirconium oxide pseudopolymorphs is investigated. The results demonstrate that spectroscopic ``fingerprints'' for each phase can be identified and the technique can be utilized for phase identification. The oxygen K-edge spectra are analyzed in detail and the spectral features are interpreted within the context of the electronic structure of zirconia. Comparisons between theory and experiment reveal coincidences which can result in misleading interpretations of the energy-loss and x-ray absorption spectra. It is shown that the effect of dopant atoms and oxygen vacancies in stabilized zirconias must be considered in order to derive the correct interpretation of the spectra. \textcopyright{} 1996 The American Physical Society.