The structuralphase transition fromfluorite to pyrochloreand thestrength of thecoordination bond of
Zr-O in Gd2Zr2O7 were investigated by XANES spectra of both O and Zr K-edge. The energy difference
of the O K-edge absorption spectra at 532 and 536 eV was assigned to the crystal field splitting energy of
the 4d orbital (E4d, t2g and eg) of the Zr ion. Also, in the samples prepared at higher temperatures, the 536 eV peak moves slightly to higher energy, whereas the absorption energy of 532 eV peak does not shift. A
correlation between E4d and the strength of interaction between Zr (4d) and O (2p) orbitals has been
found. Furthermore, two Zr K-edge absorptions at 18020 and 18030 eV of Gd2Zr2O7
have been observed; the splitting energy (E), peak intensity ratio (I18030/I18020),
and FWHM of the first derivative of the absorption curve depend on the preparation temperatures.
The effect of crystal symmetry and Zr-O bonding character on the XANES spectral profile was discussed.
Journal of the Chinese Chemical Society=中國化學會會誌 56(3), pp.543-548