Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Crystal and Magnetic Structure of CaCo{1.86}As2 Studied by X-ray and
  Neutron Diffraction   Neutron and x-ray diffraction measurements are presented for powders and
single crystals of CaCo{1.86}As2. The crystal structure is a
collapsed-tetragonal ThCr2Si2-type structure as previously reported, but with
7(1)% vacancies on the Co sites corresponding to the composition
CaCo{1.86(2)}As2. The thermal expansion coefficients for both the a- and c-axes
are positive from 10 to 300 K. Neutron diffraction measurements on single
crystals demonstrate the onset of A-type collinear antiferromagnetic order
below the Neel temperature TN = 52(1) K with the ordered moments directed along
the tetragonal c-axis, aligned ferromagnetically in the ab-plane and
antiferromagnetically stacked along the c-axis.

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The categories of this paper are: cs
9
The categories of this paper are: nlin
16
The categories of this paper are: stat
2
The categories of this paper are: math
37
The categories of this paper are: supr-con
12
The categories of this paper are: nucl-th
30
The categories of this paper are: q-alg
31
The categories of this paper are: ao-sci
7
The categories of this paper are: hep-th
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The categories of this paper are: hep-ph
24
The categories of this paper are: dg-ga
13
The categories of this paper are: quant-ph
27
The categories of this paper are: comp-gas
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The categories of this paper are: q-fin
28
The categories of this paper are: alg-geom
3
The categories of this paper are: physics