Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The high temperature expansion of the classical $XYZ$ chain   We present the $\beta$-expansion of the Helmholtz free energy of the
classical $XYZ$ model, with a single-ion anisotropy term and in the presence of
an external magnetic field, up to order $\beta^{12}$. We compare our results to
the numerical solution of Joyce's [Phys. Rev. Lett. 19, 581 (1967)] expression
for the thermodynamics of the $XXZ$ classical model, with neither single-ion
anisotropy term nor external magnetic field. This comparison shows that the
derived analytical expansion is valid for intermediate temperatures such as
$kT/J_x \approx 0.5$. We show that the specific heat and magnetic
susceptibility of the spin-2 antiferromagnetic chain can be approximated by
their respective classical results, up to $kT/J \approx 0.8$, within an error
of 2.5%. In the absence of an external magnetic field, the ferromagnetic and
antiferromagnetic chains have the same classical Helmholtz free energy. We show
how this two types of media react to the presence of an external magnetic
field.

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The categories of this paper are: adap-org
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The categories of this paper are: econ
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The categories of this paper are: eess
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The categories of this paper are: cs
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The categories of this paper are: math-ph
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The categories of this paper are: hep-ex
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The categories of this paper are: quant-ph
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The categories of this paper are: mtrl-th
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The categories of this paper are: hep-th
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The categories of this paper are: dg-ga
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The categories of this paper are: alg-geom
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The categories of this paper are: ao-sci
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The categories of this paper are: q-bio
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The categories of this paper are: patt-sol
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The categories of this paper are: nucl-th
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The categories of this paper are: nucl-ex