Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Density functional theory analysis of flexural modes, elastic constants,
  and corrugations in strained graphene   Ab initio density functional theory has been used to analyze flexural modes,
elastic constants, and atomic corrugations on single and bi-layer graphene.
Frequencies of flexural modes are sensitive to compressive stress; its
variation under stress can be related to the anomalous thermal expansion via a
simple model based in classical Elasticity Theory [Phys. Rev. B 86, 144103].
Under compression, flexural modes are responsible for a long wavelength
rippling with a large amplitude and a marked anharmonic behavior. This is
compared with corrugations created by thermal fluctuations and the adsorption
of a light impurity (hydrogen). Typical values for the later are in the
sub-Angstrom regime, while maximum corrugations associated to bending modes
quickly increase up to a few Angstroms under a compressive stress, due to the
intrinsic instability of flexural modes

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The categories of this paper are: chem-ph
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The categories of this paper are: nlin
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The categories of this paper are: atom-ph
14
The categories of this paper are: math-ph
28
The categories of this paper are: alg-geom
17
The categories of this paper are: q-fin
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The categories of this paper are: solv-int
3
The categories of this paper are: physics
22
The categories of this paper are: chao-dyn
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The categories of this paper are: nucl-ex
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The categories of this paper are: q-alg
21
The categories of this paper are: adap-org
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The categories of this paper are: bayes-an
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The categories of this paper are: funct-an
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The categories of this paper are: supr-con
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The categories of this paper are: mtrl-th