Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Negative thermal expansion and magnetoelastic coupling in the breathing
  pyrochlore lattice material LiGaCr4S8   The physical properties of the spinel LiGaCr4S8 have been studied with
neutron diffraction, X-ray diffraction, magnetic susceptibility and heat
capacity measurements. The neutron diffraction and synchrotron X-ray
diffraction data reveal negative thermal expansion (NTE) below 111(4) K. The
magnetic susceptibility deviates from Curie-Weiss behavior with the onset of
NTE. At low temperature a broad peak in the magnetic susceptibility at 10.3(3)
K is accompanied by the return of normal thermal expansion. First principles
calculations find a strong coupling between the lattice and the simulated
magnetic ground state. These results indicate strong magnetoelastic coupling in
LiGaCr4S8.

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The categories of this paper are: hep-ex
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The categories of this paper are: nlin
36
The categories of this paper are: cmp-lg
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The categories of this paper are: econ
34
The categories of this paper are: chem-ph
5
The categories of this paper are: gr-qc
29
The categories of this paper are: funct-an
11
The categories of this paper are: hep-lat
12
The categories of this paper are: nucl-th
25
The categories of this paper are: patt-sol
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The categories of this paper are: eess
28
The categories of this paper are: alg-geom
22
The categories of this paper are: chao-dyn
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The categories of this paper are: hep-th
37
The categories of this paper are: supr-con
32
The categories of this paper are: atom-ph