Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Characterization of silicon thin overlayers on rutile \ce{TiO2}
  (110)-(1x1)   Silicon thin films for coverages ($\theta$) between 0.3 and 3 monolayers have
been grown on rutile \ce{TiO2}(110)-(1x1) at room temperature and studied by
x-ray and ultra-violet photoelectron spectroscopies, Auger electron
spectroscopy, and low energy electron diffraction (LEED). A clear evidence of a
strong \ce{Si}/\ce{TiO2} interaction consistent with the high affinity of O for
Si has been found. The Ti cations on the substrate are reduced, while the Si
film is oxidized, yielding \ce{SiO2} and a mixture of silicon suboxides.
Neutral Si atoms are observed at a coverage of 3 monolayers. At the interface
region we observe the formation of cross-linking Ti-O-Si bonds. The thin Si
overlayer strongly attenuates the $(1 \times 1)$ LEED pattern from the
substrate. Finally, thermal annealing results in the improvement of the
\ce{SiO2} stoichiometry, but the surface order is not recovered. Using
ab-initio density functional theory we have obtained optimum geometrical
configurations and corresponding density of states for 1/3 \le \theta \le 1$
monolayers of Si adsorbed on the $1 \times 1$ two-dimensional unit cell.

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The categories of this paper are: atom-ph
31
The categories of this paper are: ao-sci
9
The categories of this paper are: nlin
28
The categories of this paper are: alg-geom
13
The categories of this paper are: quant-ph
6
The categories of this paper are: astro-ph
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The categories of this paper are: chem-ph
2
The categories of this paper are: math
11
The categories of this paper are: hep-lat
24
The categories of this paper are: dg-ga
16
The categories of this paper are: stat
12
The categories of this paper are: nucl-th
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The categories of this paper are: mtrl-th
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The categories of this paper are: q-alg
25
The categories of this paper are: patt-sol
19
The categories of this paper are: eess