Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Analytical Hartree-Fock gradients with respect to the cell parameter:
  systems periodic in one and two dimensions
1
The categories of this paper are: cs
13
The categories of this paper are: quant-ph
16
The categories of this paper are: stat
7
The categories of this paper are: hep-th
37
The categories of this paper are: supr-con
8
The categories of this paper are: hep-ex
36
The categories of this paper are: cmp-lg
33
The categories of this paper are: plasm-ph
21
The categories of this paper are: adap-org
28
The categories of this paper are: alg-geom
15
The categories of this paper are: nucl-ex
31
The categories of this paper are: ao-sci
4
The categories of this paper are: cond-mat
29
The categories of this paper are: funct-an
25
The categories of this paper are: patt-sol
35
The categories of this paper are: mtrl-th