Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Density-Functional Theory Study of the Optoelectronic Properties of
  {\pi}-Conjugated Copolymers for Organic Light-Emitting Diodes
8
The categories of this paper are: hep-ex
35
The categories of this paper are: mtrl-th
5
The categories of this paper are: gr-qc
13
The categories of this paper are: quant-ph
32
The categories of this paper are: atom-ph
4
The categories of this paper are: cond-mat
23
The categories of this paper are: solv-int
29
The categories of this paper are: funct-an
36
The categories of this paper are: cmp-lg
24
The categories of this paper are: dg-ga
19
The categories of this paper are: eess
12
The categories of this paper are: nucl-th
20
The categories of this paper are: acc-phys
10
The categories of this paper are: q-bio
28
The categories of this paper are: alg-geom
9
The categories of this paper are: nlin