Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Species-to-species rate coefficients for the $\rm H_3^+ + H_2$ reacting
  system
31
The categories of this paper are: ao-sci
10
The categories of this paper are: q-bio
35
The categories of this paper are: mtrl-th
5
The categories of this paper are: gr-qc
19
The categories of this paper are: eess
30
The categories of this paper are: q-alg
24
The categories of this paper are: dg-ga
9
The categories of this paper are: nlin
36
The categories of this paper are: cmp-lg
12
The categories of this paper are: nucl-th
18
The categories of this paper are: econ
33
The categories of this paper are: plasm-ph
34
The categories of this paper are: chem-ph
3
The categories of this paper are: physics
25
The categories of this paper are: patt-sol
32
The categories of this paper are: atom-ph