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DOE OSTI · 1678718

Simulated field-modulated x-ray absorption in titania

Darapaneni, Pragathi·Meyer, Alexander M.·Sereda, Mykola·Bruner, Adam·Dorman, James A.·Lopata, Kenneth
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Abstract

Here, we present a method to compute the x-ray absorption near-edge structure (XANES) spectra of solid-state transition metal oxides using real-time time-dependent density functional theory, including spin–orbit coupling effects. This was performed on bulk-mimicking anatase titania (TiO 2 ) clusters, which allows for the use of hybrid functionals and atom-centered all electron basis sets. Furthermore, this method was employed to calculate the shifts in the XANES spectra of the Ti L-edge in the presence of applied electric fields to understand how external fields can modify the electronic structure, and how this can be probed using x-ray absorption spectroscopy. Specifically, the onset of t 2g peaks in the Ti L-edge was observed to red shift and the e g peaks were observed to blue shift with increasing fields, attributed to changes in the hybridization of the conduction band (3d) orbitals.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRYAb-initio methodsCrystalline solidsElectric fieldsElectrostaticsHybrid density functional calculationsSpin-orbit interactionsStrong field induced spectraTime dependent density functional theoryX-ray absorption spectroscopy

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Darapaneni, Pragathi, Meyer, Alexander M., Sereda, Mykola, Bruner, Adam, Dorman, James A., Lopata, Kenneth. 2020-08-04. Simulated field-modulated x-ray absorption in titania. https://doi.org/10.1063/5.0009677

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