Experimental and Calculated Ti K-Edge XANES Spectra of Pb1-xLaxTiO3 Ferroelectric Ceramic Compounds
Abstract
The X-ray absorption near-edge structures (XANES) at the Ti K-edge of Pb1-xLaxTiO3 ferroelectric ceramic compounds are analyzed as a function of the sample composition. The calculated XANES spectra using the FEFF8.2 code are compared with experimental data. Experimental results show that the local distortion around Ti atoms has different composition dependence as compared to the crystallographic structure. Moreover, this distortion is also observed in samples presenting a crystallographically cubic phase. The agreement between experimental XANES spectra and theoretical ones deduced from the XRD results was good only for undoped and weakly doped samples. The use of structural models based on the XRD technique for samples containing higher amounts of lanthanum is not appropriate to describe correctly the local order around Ti atoms in this system.
- Authors:
- Intituto de Fisica de Sao Carlos, Universidade de Sao Paulo, C. P. 369, 13560-970, Sao Carlos, SP (Brazil)
- Laboratoire de Physique Structurale des Molecules et Materiaux, Universite Paris XII - Creteil Cedex (France)
- Departamento de Fisica, Universidade Federal de Sao Carlos, Sao Carlos - SP (Brazil)
- Publication Date:
- OSTI Identifier:
- 21054664
- Resource Type:
- Journal Article
- Resource Relation:
- Journal Name: AIP Conference Proceedings; Journal Volume: 882; Journal Issue: 1; Conference: XAFS13: 13. international conference on X-ray absorption fine structure, Stanford, CA (United States), 9-14 Jul 2006; Other Information: DOI: 10.1063/1.2644571; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 36 MATERIALS SCIENCE; ABSORPTION SPECTRA; ABSORPTION SPECTROSCOPY; ATOMS; CERAMICS; CRYSTAL STRUCTURE; DOPED MATERIALS; FERROELECTRIC MATERIALS; LANTHANUM; LANTHANUM COMPOUNDS; LEAD COMPOUNDS; TITANATES; X-RAY DIFFRACTION; X-RAY SPECTRA; X-RAY SPECTROSCOPY
Citation Formats
Mastelaro, V. R., Neves, P. P., Michalowicz, A., and Eiras, J. A.. Experimental and Calculated Ti K-Edge XANES Spectra of Pb1-xLaxTiO3 Ferroelectric Ceramic Compounds. United States: N. p., 2007.
Web. doi:10.1063/1.2644571.
Mastelaro, V. R., Neves, P. P., Michalowicz, A., & Eiras, J. A.. Experimental and Calculated Ti K-Edge XANES Spectra of Pb1-xLaxTiO3 Ferroelectric Ceramic Compounds. United States. doi:10.1063/1.2644571.
Mastelaro, V. R., Neves, P. P., Michalowicz, A., and Eiras, J. A.. Fri .
"Experimental and Calculated Ti K-Edge XANES Spectra of Pb1-xLaxTiO3 Ferroelectric Ceramic Compounds". United States.
doi:10.1063/1.2644571.
@article{osti_21054664,
title = {Experimental and Calculated Ti K-Edge XANES Spectra of Pb1-xLaxTiO3 Ferroelectric Ceramic Compounds},
author = {Mastelaro, V. R. and Neves, P. P. and Michalowicz, A. and Eiras, J. A.},
abstractNote = {The X-ray absorption near-edge structures (XANES) at the Ti K-edge of Pb1-xLaxTiO3 ferroelectric ceramic compounds are analyzed as a function of the sample composition. The calculated XANES spectra using the FEFF8.2 code are compared with experimental data. Experimental results show that the local distortion around Ti atoms has different composition dependence as compared to the crystallographic structure. Moreover, this distortion is also observed in samples presenting a crystallographically cubic phase. The agreement between experimental XANES spectra and theoretical ones deduced from the XRD results was good only for undoped and weakly doped samples. The use of structural models based on the XRD technique for samples containing higher amounts of lanthanum is not appropriate to describe correctly the local order around Ti atoms in this system.},
doi = {10.1063/1.2644571},
journal = {AIP Conference Proceedings},
number = 1,
volume = 882,
place = {United States},
year = {Fri Feb 02 00:00:00 EST 2007},
month = {Fri Feb 02 00:00:00 EST 2007}
}
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