Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Many-spin effects and tunneling splittings in Mn12 magnetic molecules   We calculate the tunneling splittings in a Mn$_{12}$ magnetic molecule taking
into account its internal many-spin structure. We discuss the precision and
reliability of these calculations and show that restricting the basis (limiting
the number of excitations taken into account) may lead to significant error
(orders of magnitude) in the resulting tunneling splittings for the lowest
energy levels, so that an intuitive picture of different decoupled energy
scales does not hold in this case. Possible routes for further development of
the many-spin model of Mn$_{12}$ are discussed.

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The categories of this paper are: adap-org
31
The categories of this paper are: ao-sci
9
The categories of this paper are: nlin
11
The categories of this paper are: hep-lat
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The categories of this paper are: solv-int
33
The categories of this paper are: plasm-ph
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The categories of this paper are: alg-geom
8
The categories of this paper are: hep-ex
0
The categories of this paper are: hep-ph
35
The categories of this paper are: mtrl-th
5
The categories of this paper are: gr-qc
12
The categories of this paper are: nucl-th
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The categories of this paper are: cs
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The categories of this paper are: dg-ga
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The categories of this paper are: bayes-an
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The categories of this paper are: hep-th