Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Biphenylene monolayer as a two-dimensional nonbenzenoid carbon
  allotrope: A first-principles study   In a very recent accomplishment, the two-dimensional form of Biphenylene
network (BPN) has been successfully fabricated [Fan et al., Science, 372,
852-856 (2021)]. Motivated by this exciting experimental result on 2D layered
BPN structure, herein we perform detailed density functional theory-based
first-principles calculations, for the first time, in order to gain insight
into the structural, electronic and optical properties of this promising
nanomaterial. Our theoretica results reveal the BPN structure is constructed
from three rings of tetragon, hexagon and octagon, meanwhile the electron
localization function shows very strong bonds between the C atoms in the
structure. The dynamical stability of BPN is verified via the phonon band
dispersion calculations. The mechanical properties reveal the brittle behavior
of BPN monolayer. The Youngs modulus has been computed as 0.1 TPa, which is
smaller than the corresponding value of graphene, while the Poissons ratio
determined to be 0.26 is larger than that of graphene. The band structure is
evaluated to show the electronic features of the material; determining the BPN
monolayer as metallic with a band gap of zero. The optical properties (real and
imaginary parts of the dielectric function, and the absorption spectrum)
uncover BPN as an insulator along the zz direction, while owning metallic
properties in xx and yy directions. We anticipate that our discoveries will
pave the way to the successful implementation of this new 2D allotrope of
carbon in advanced nanoelectronics.

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The categories of this paper are: acc-phys
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The categories of this paper are: patt-sol
1
The categories of this paper are: cs
34
The categories of this paper are: chem-ph
14
The categories of this paper are: math-ph
23
The categories of this paper are: solv-int
6
The categories of this paper are: astro-ph
33
The categories of this paper are: plasm-ph
15
The categories of this paper are: nucl-ex
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The categories of this paper are: dg-ga
7
The categories of this paper are: hep-th
29
The categories of this paper are: funct-an
37
The categories of this paper are: supr-con
8
The categories of this paper are: hep-ex
28
The categories of this paper are: alg-geom
5
The categories of this paper are: gr-qc