Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Twisted Helical shaped Graphene Nano-Ribbons: Role of Symmetries and
  Passivation   The Hydrogen and Fluorine planar armchairs graphene nanoribbons (H and F
AGNRs), subjected to twist deformation within fixed periodic boundary
conditions, eventually morph to a helical conformations are investigated at few
tractable points. Unlike structural properties, no effect of symmetries on
mechanical properties is observed, though passivation does have a significant
effect on mechanical as well as on electrical properties. Hookes law for
severely twisted AGNRs indicates the high elasticity of H-AGNRs whereas the
F-AGNRs shows plasticity after threshold torsional strain. Torsional
stress($E_{\theta}$) is approximated from the variation in total
energy(${\Delta}E$) with square of torsional strain(${\theta}^4 {\Sigma}^4$).
Further, the effect of passivation on the electronic properties of helical
conformations with different torsional strain is decisive in metal-to-semimetal
and semimetal-to-metal transition. The band gap response of narrow GNRs N=6, 7
and 8, within a fixed cell under sever twisting arranged itself in two group as
(i) monotonously increasing for q=0,2 and (ii) decreasing for q=1, here
q=mod(N,3) in effective strain space (${\theta}^2 {\Sigma}^2$). This trend has
also been observed for Fluorine passivated AGNRs, though band gap of N=7
F-AGNRs drops from 0.95eV to 0.05eV at extreme torsional strain forming Dirac
cone at K allows dissipation less transport for longer wavelength electrons.

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The categories of this paper are: hep-ex
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The categories of this paper are: hep-lat
28
The categories of this paper are: alg-geom
1
The categories of this paper are: cs
30
The categories of this paper are: q-alg
6
The categories of this paper are: astro-ph
3
The categories of this paper are: physics
31
The categories of this paper are: ao-sci
13
The categories of this paper are: quant-ph
25
The categories of this paper are: patt-sol
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The categories of this paper are: nlin
24
The categories of this paper are: dg-ga
23
The categories of this paper are: solv-int
5
The categories of this paper are: gr-qc
19
The categories of this paper are: eess
36
The categories of this paper are: cmp-lg