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Effects of Local Atomic Order on the Pre-Edge Structure in the Ti K X-Ray Absorption Spectra of Perovskite CaTi1-xZrxO3

V. Krayzman·I. Levin·J. C. Woicik·D. Yoder·D. A. Fischer
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Abstract

The effects of local B-cation (Ti, Zr) distribution and octahedral tilting on the pre-edge structure in the Ti X-ray absorption K-spectra of the CaTi1-xZrxO3 perovskite solid solutions were investigated. Experimental spectra for the disordered CaTi1-xZrxO3 samples revealed systematic variations of the pre-edge peak intensities with the x-values. Multiple-scattering calculations using 75-atom clusters Ti(TiO6)6-n(ZrO6)nCa8O24 were conducted to interpret these differences. The origin of the lowest unoccupied states in the conduction band of the CaTi1-xZrxO3 was determined from the analyses of X-ray absorption near-edge structure of the O K-edge. The calculations reproduced the experimental spectra and demonstrated that the differences in the intensities of certain pre-edge feature are dominated by the probability of finding a Zr atom in the first B-cation coordination sphere around the absorbing Ti. The pre-edge structure appeared to be sensitive to small changes in the value of this probability, so that the pre-edge intensities could be used effectively to compare the extent of local B-site order in perovskite solid solution samples having similar chemical composition but processed differently.

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V. Krayzman, I. Levin, J. C. Woicik, D. Yoder, D. A. Fischer. 2006-11-10. Effects of Local Atomic Order on the Pre-Edge Structure in the Ti K X-Ray Absorption Spectra of Perovskite CaTi1-xZrxO3. https://doi.org/10.1103/physrevb.74.224104

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