Temperature dependence of pre-edge features in TiK-edge XANES spectra forATiO3(A= Ca and Sr),A2TiO4(A= Mg and Fe), TiO2rutile and TiO2anatase

Abstract

XANES (X-ray absorption near-edge structure) spectra of the TiK-edges ofATiO3(A= Ca and Sr),A2TiO4(A= Mg and Fe), TiO2rutile and TiO2anatase were measured in the temperature range 20–900 K. Ti atoms for all samples were located in TiO6octahedral sites. The absorption intensity invariant point (AIIP) was found to be between the pre-edge and post-edge. After the AIIP, amplitudes damped due to Debye–Waller factor effects with temperature. Amplitudes in the pre-edge region increased with temperature normally by thermal vibration. Use of the AIIP peak intensity as a standard point enables a quantitative comparison of the intensity of the pre-edge peaks in various titanium compounds over a wide temperature range.