Experimental and Calculated Ti K-Edge XANES Spectra of Pb1-xLaxTiO3 Ferroelectric Ceramic Compounds
نویسندگان
چکیده
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.
منابع مشابه
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