Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Tuning electronic properties in graphene quantum dots by chemical
  functionalization: Density functional theory calculations   The electronic energy gap and total dipole moment of chemically
functionalized hexagonal and triangular graphene quantum dots are investigated
by the density functional theory. It has been found that the energy gap can be
efficiently tuned in the selected clusters by edge passivation with different
elements or groups. Edge passivation with oxygen provides a considerable
decrease of the large energy gap observed in hexagonal nanodots. The edge
states and energy gap in triangular graphene quantum dots can also be
manipulated by passivation with fluorine. The total dipole moment strongly
depends on: (a) the shape and edge termination of the graphene quantum dot, (b)
the attached group, and (c) the position to which the groups are attached. With
respect to the shape, edge termination, and the attached group the chemically
modified hexagonal-armchair quantum dot has the highest total dipole moment.
Depending on the position of the attached groups, the total dipole can be
increased, decreased, or eliminated. The significant features, the tunable
energy gap and total dipole moment, of the functionalized graphene quantum dots
are confirmed by the stability calculations. The obtained positive binding
energy and positive frequencies in the infrared spectra imply that all the
selected clusters are stable under edge functionalization and passivation with
various groups and elements.

24
The categories of this paper are: dg-ga
33
The categories of this paper are: plasm-ph
9
The categories of this paper are: nlin
18
The categories of this paper are: econ
31
The categories of this paper are: ao-sci
29
The categories of this paper are: funct-an
17
The categories of this paper are: q-fin
16
The categories of this paper are: stat
26
The categories of this paper are: bayes-an
2
The categories of this paper are: math
32
The categories of this paper are: atom-ph
8
The categories of this paper are: hep-ex
22
The categories of this paper are: chao-dyn
15
The categories of this paper are: nucl-ex
1
The categories of this paper are: cs
37
The categories of this paper are: supr-con