Dataset Information

X-ray absorption linear dichroism at the Ti K-edge of rutile (001) TiO2 single crystal.

ABSTRACT: X-ray absorption linear dichroism of rutile TiO2 at the Ti K-edge provides information about the electronic states involved in the pre-edge transitions. Here, linear dichroism with high energy resolution is analyzed in combination with ab?initio finite difference method calculations and spherical tensor analysis. It provides an assignment of the three pre-edge peaks beyond the octahedral crystal field splitting approximation and estimates the spatial extension of the corresponding final states. It is then discussed for the first time the X-ray absorption (XAS) of pentacoordinated titanium atoms due to oxygen vacancies and it is found that, similarly to anatase TiO2, rutile is expected to exhibit a transition on the low-energy side of peak A3. Its apparent absence in the experiment is related to the degree of p-d orbital mixing which is small in rutile due to its centrosymmetric point group. A recent XAS linear dichroism study on anatase TiO2 single crystals has shown that peak A2 has an intrinsic origin and is due to a quadrupolar transition to the 3d energy levels. In rutile, due to its centrosymmetric point group, the corresponding peak A2 has a small dipole moment explaining the weak transition. The results are confronted with recent picosecond X-ray absorption spectroscopy on rutile TiO2 nanoparticles.

SUBMITTER: Rossi TC

PROVIDER: S-EPMC7064109 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature

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X-ray absorption linear dichroism at the Ti K-edge of rutile (001) TiO<sub>2</sub> single crystal.

Rossi T C TC Grolimund D D Cannelli O O Mancini G F GF Bacellar C C Kinschel D D Rouxel J R JR Ohannessian N N Pergolesi D D Chergui M M

Journal of synchrotron radiation 20200214 Pt 2

X-ray absorption linear dichroism of rutile TiO<sub>2</sub> at the Ti K-edge provides information about the electronic states involved in the pre-edge transitions. Here, linear dichroism with high energy resolution is analyzed in combination with ab initio finite difference method calculations and spherical tensor analysis. It provides an assignment of the three pre-edge peaks beyond the octahedral crystal field splitting approximation and estimates the spatial extension of the corresponding fin ...[more]

PMID: 32153281

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Dataset Information

X-ray absorption linear dichroism at the Ti K-edge of rutile (001) TiO2 single crystal.

Publications

X-ray absorption linear dichroism at the Ti K-edge of rutile (001) TiO<sub>2</sub> single crystal.

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Dataset Information

X-ray absorption linear dichroism at the Ti K-edge of rutile (001) TiO2 single crystal.

Publications

X-ray absorption linear dichroism at the Ti K-edge of rutile (001) TiO&lt;sub&gt;2&lt;/sub&gt; single crystal.

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OmicsDI is part of the ELIXIR infrastructure

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X-ray absorption linear dichroism at the Ti K-edge of rutile (001) TiO<sub>2</sub> single crystal.