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arXiv · 1009.1479

Observation and destruction of an elusive adsorbate with STM: O$_2$/TiO$_2$

Philipp Scheiber·Alexander Riss·Michael Schmid·Peter Varga·Ulrike Diebold
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Abstract

When a slightly defective rutile TiO$_2$(110) surface is exposed to O$_2$ at elevated temperatures, the molecule dissociates at defects, filling O vacancies (\ov) and creating O adatoms (\oad) on {\tifc} rows. The adsorption of molecular O$_2$ at low temperatures has remained controversial. Low-Temperature Scanning Tunneling Microscopy (LT-STM) of O$_2$, dosed on TiO$_2$(110) at a sample temperature of $\approx$ 100 K and imaged at 17 K, shows a molecular precursor at \ov as a faint change in contrast. The adsorbed O$_2$ easily dissociates during the STM measurements, and formation of \oad's at both sides of the original \ov is observed.

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Philipp Scheiber, Alexander Riss, Michael Schmid, Peter Varga, Ulrike Diebold. 2010-10-15. Observation and destruction of an elusive adsorbate with STM: O$_2$/TiO$_2$. https://doi.org/10.1103/physrevlett.105.216101

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