Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: NMR characterization of spin-1/2 alternating antiferromagnetic chains in
  the high-pressure phase of (VO)2P2O7   Local-susceptibility measurements via the NMR shifts of $^{31}$P and $^{51}$V
nuclei in the high-pressure phase of (VO)$_{2}$P$_{2}$O$_{7}$ confirmed the
existence of a unique alternating antiferromagnetic chain with a zero-field
spin gap of 34 K. The $^{31}$P nuclear spin-lattice relaxation rate scales with
the uniform spin susceptibility below about 15 K which shows that the
temperature dependence of both the static and dynamical spin susceptibilities
becomes identical at temperatures not far below the spin-gap energy.

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The categories of this paper are: eess
27
The categories of this paper are: comp-gas
10
The categories of this paper are: q-bio
15
The categories of this paper are: nucl-ex
8
The categories of this paper are: hep-ex
30
The categories of this paper are: q-alg
37
The categories of this paper are: supr-con
14
The categories of this paper are: math-ph
23
The categories of this paper are: solv-int
20
The categories of this paper are: acc-phys
16
The categories of this paper are: stat
11
The categories of this paper are: hep-lat
1
The categories of this paper are: cs
28
The categories of this paper are: alg-geom
31
The categories of this paper are: ao-sci
34
The categories of this paper are: chem-ph