Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Raman and IR spectra of graphdiyne nanoribbons   {\gamma}-graphdiyne is a 2D carbon structure beyond graphene: it is formed by
sp and sp2 carbon atoms organized as hexagonal rings connected by linear links,
and it is predicted to be a semiconductor. The lateral confinement of
{\gamma}-graphdiyne nanoribbons significantly affects the electronic and
vibrational properties. By means of periodic Density Functional Theory (DFT)
calculations we investigate here the electronic band structure, the Raman and
IR spectra of the {\gamma}-graphdiyne 2D crystal and related nanoribbons. We
discuss the effect of the functional and basis set on the evaluation of the
band gap, highlighting the reliability of hybrid functionals. By joining DFT
calculations with a symmetry analysis, we assign in detail the IR and Raman
spectra of {\gamma}-graphdiyne. On this basis we show the modulation of the gap
in nanoribbons of increasing width and different edges (armchair, zigzag). We
assess how confinement affects the Raman and IR spectra of such nanoribbons by
comparing their vibrational modes with the phonons of the parent 2D crystal.
Our symmetry-based classification allows identifying the marker bands sensitive
to the edge structure and lateral confinement of nanoribbons of increasing
width. These results show the effectiveness of vibrational spectroscopy for the
characterization of such nanostructures.

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The categories of this paper are: physics
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The categories of this paper are: patt-sol
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The categories of this paper are: nucl-th
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The categories of this paper are: alg-geom
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The categories of this paper are: q-alg
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The categories of this paper are: cmp-lg
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The categories of this paper are: econ
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The categories of this paper are: math-ph
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The categories of this paper are: gr-qc
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The categories of this paper are: hep-th
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The categories of this paper are: ao-sci
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The categories of this paper are: nucl-ex
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The categories of this paper are: q-bio
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The categories of this paper are: cs
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The categories of this paper are: funct-an
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The categories of this paper are: acc-phys