Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Lattice effects and entropy release at the low-temperature phase
  transition in the spin-liquid candidate
  $\kappa$-(BEDT-TTF)$_{2}$Cu$_{2}$(CN)$_{3}$   The spin-liquid candidate $\kappa$-(BEDT-TTF)$_{2}$Cu$_{2}$(CN)$_{3}$ has
been studied by measuring the uniaxial expansion coefficients $\alpha_{i}$, the
specific heat, and magnetic susceptibility. Special emphasis was placed on the
mysterious anomaly around 6 K - a potential spin-liquid instability. Distinct
and strongly anisotropic lattice effects have been observed at 6 K, clearly
identifying this feature as a second-order phase transition. Owing to the large
anomalies in $\alpha_{i}$, the application of Gr\"{u}neisen scaling has enabled
us to determine the corresponding specific heat contribution and the entropy
release. Comparison of the latter with available spin models suggests that spin
degrees of freedom alone cannot account for the phase transition. Scenarios,
involving charge degrees of freedom, are discussed. charge degrees of freedom,
are discussed.

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The categories of this paper are: econ
3
The categories of this paper are: physics
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The categories of this paper are: q-fin
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The categories of this paper are: math-ph
16
The categories of this paper are: stat
24
The categories of this paper are: dg-ga
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The categories of this paper are: cmp-lg
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The categories of this paper are: patt-sol
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The categories of this paper are: alg-geom
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The categories of this paper are: eess
9
The categories of this paper are: nlin
35
The categories of this paper are: mtrl-th
1
The categories of this paper are: cs
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The categories of this paper are: hep-lat
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The categories of this paper are: nucl-th
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The categories of this paper are: atom-ph