Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: First principles design of 2 dimensional Nickel dichalcogenide Janus
  materials NiXY (X,Y=S,Se,Te)
9
The categories of this paper are: nlin
18
The categories of this paper are: econ
17
The categories of this paper are: q-fin
33
The categories of this paper are: plasm-ph
26
The categories of this paper are: bayes-an
35
The categories of this paper are: mtrl-th
32
The categories of this paper are: atom-ph
7
The categories of this paper are: hep-th
1
The categories of this paper are: cs
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
28
The categories of this paper are: alg-geom
16
The categories of this paper are: stat
13
The categories of this paper are: quant-ph
5
The categories of this paper are: gr-qc