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arXiv · 1702.01555

On the oxidation state of titanium in titanium dioxide

Daniel Koch·Sergei Manzhos
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Abstract

The oxidation state of titanium in titanium dioxide is commonly assumed to be +4. This assumption is used ubiquitously to rationalize phenomena observed with TiO2. We present a comprehensive electronic structure investigation of Ti ions, TiO2 molecules and TiO2 bulk crystals, using different density functional theory and wave function-based approaches, which suggests a lower oxidation state (+3). Specifically, there is evidence of a significant remaining contribution from valence s and d electrons of Ti, including the presence of a nuclear cusp around the Ti core. The charge corresponding to valence s and d states of Ti amounts to 1 e. The commonly assumed picture may therefore have to be revised.

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Daniel Koch, Sergei Manzhos. 2017-02-06. On the oxidation state of titanium in titanium dioxide. https://doi.org/10.1021/acs.jpclett.7b00313

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