Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Graphene on the C-terminated SiC (000 $\bar{1}$) surface: An ab initio
  study   The atomic and electronic structures of a graphene layer on top of the
$(2\times2)$ reconstruction of the SiC (000$\bar{1}$) surface are studied from
ab initio calculations. At variance with the (0001) face, no C bufferlayer is
found here. Si adatoms passivate the substrate surface so that the very first C
layer presents a linear dispersion characteristic of graphene. A small
graphene-substrate interaction remains in agreement with scanning tunneling
experiments (F.Hiebel et al. {\it Phys. Rev. B} {\bf 78} 153412 (2008)). The
stacking geometry has little influence on the interaction which explains the
rotational disorder observed on this face.

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The categories of this paper are: astro-ph
2
The categories of this paper are: math
10
The categories of this paper are: q-bio
29
The categories of this paper are: funct-an
12
The categories of this paper are: nucl-th
32
The categories of this paper are: atom-ph
5
The categories of this paper are: gr-qc
23
The categories of this paper are: solv-int
25
The categories of this paper are: patt-sol
37
The categories of this paper are: supr-con
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The categories of this paper are: q-fin
19
The categories of this paper are: eess
21
The categories of this paper are: adap-org
20
The categories of this paper are: acc-phys
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The categories of this paper are: hep-ex
7
The categories of this paper are: hep-th