Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Cohesion Energetics of Carbon Allotropes : Quantum Monte Carlo Study   We have performed quantum Monte Carlo calculations to study the cohesion
energetics of carbon allotropes, including $sp^3$-bonded diamond, $sp^2$-bonded
graphene, $sp$-$sp^2$ hybridized graphynes, and $sp$-bonded carbyne. The
computed cohesive energies of diamond and graphene are found to be in excellent
agreement with the corresponding values determined experimentally for diamond
and graphite, respectively, when the zero-point energies, along with the
interlayer binding in the case of graphite, are included. We have also found
that the cohesive energy of graphyne decreases systematically as the ratio of
$sp$-bonded carbon atoms increases. The cohesive energy of $\gamma$-graphyne,
the most energetically-stable graphyne, turns out to be 6.766(6) eV/atom, which
is smaller than that of graphene by 0.698(12) eV/atom. Experimental difficulty
in synthesizing graphynes could be explained by their significantly smaller
cohesive energies. Finally we conclude that the cohesive energy of a
newly-proposed graphyne can be accurately estimated with the carbon-carbon bond
energies determined from the cohesive energies of graphene and three different
graphynes considered here.

31
The categories of this paper are: ao-sci
10
The categories of this paper are: q-bio
36
The categories of this paper are: cmp-lg
8
The categories of this paper are: hep-ex
5
The categories of this paper are: gr-qc
20
The categories of this paper are: acc-phys
11
The categories of this paper are: hep-lat
6
The categories of this paper are: astro-ph
23
The categories of this paper are: solv-int
19
The categories of this paper are: eess
30
The categories of this paper are: q-alg
15
The categories of this paper are: nucl-ex
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The categories of this paper are: patt-sol
14
The categories of this paper are: math-ph
1
The categories of this paper are: cs
24
The categories of this paper are: dg-ga