Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Silicene Structures on Silver Surfaces   In this paper we report on several structures of silicene, the analog of
graphene for silicon, on the silver surfaces Ag(100), Ag(110) and Ag(111).
Deposition of Si produces honeycomb structures on these surfaces. In
particular, we present an extensive theoretical study of silicene on Ag(111)
for which several recent experimental studies have been published. Different
silicene structures were obtained only by varying the silicon coverage and/or
its atomic arrangement. All the structures studied show that silicene is
buckled, with a Si-Si nearest neighbor distance varying between 2.28 and 2.5
A{\deg} . Due to the buckling in the silicene sheet, the apparent (lateral)
Si-Si distance can be as low as 1.89 A{\deg} . We also found that for a given
coverage and symmetry, one may observe different scanning tunneling microscopy
images corresponding to structures that differ by only a translation.

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The categories of this paper are: astro-ph
2
The categories of this paper are: math
27
The categories of this paper are: comp-gas
19
The categories of this paper are: eess
20
The categories of this paper are: acc-phys
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The categories of this paper are: hep-ex
32
The categories of this paper are: atom-ph
30
The categories of this paper are: q-alg
26
The categories of this paper are: bayes-an
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The categories of this paper are: math-ph
37
The categories of this paper are: supr-con
13
The categories of this paper are: quant-ph
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The categories of this paper are: chao-dyn
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The categories of this paper are: hep-th
28
The categories of this paper are: alg-geom
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The categories of this paper are: adap-org