Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Graphyne- and Graphdiyne-based Nanoribbons: Density Functional Theory
  Calculations of Electronic Structures   We report on the configurations and electronic properties of graphyne and
graphdiyne nanoribbons with armchair and zigzag edges investigated with first
principles calculations. Our results show that all the nanoribbons are
semiconductors with suitable band gaps similar to silicon. And their band gaps
decrease as widths of nanoribbons increase. We also find that the band gap is
at the Gamma point for all graphdiyne ribbons and it is at the X point for all
graphyne ribbons. Of particular interest, the band gap of zigzag graphyne
nanoribbons show a unique step effect as the width increases. This property is
good for tuning of the energy band gap, as in a certain range of the ribbon
width, the energy gap remains constant and in reality the edge cannot be as
neat as that in a theoretic model.

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The categories of this paper are: plasm-ph
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The categories of this paper are: adap-org
30
The categories of this paper are: q-alg
24
The categories of this paper are: dg-ga
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The categories of this paper are: chem-ph
32
The categories of this paper are: atom-ph
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The categories of this paper are: chao-dyn
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The categories of this paper are: q-fin
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The categories of this paper are: bayes-an
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The categories of this paper are: supr-con
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The categories of this paper are: ao-sci
29
The categories of this paper are: funct-an
1
The categories of this paper are: cs
11
The categories of this paper are: hep-lat
16
The categories of this paper are: stat
23
The categories of this paper are: solv-int