Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Structure and magnetic properties of the Ho2Ge2O7 pyrogermanate   We report the anisotropic magnetic properties of Ho2Ge2O7 determined from dc
and ac magnetization, specific heat and powder neutron diffraction experiments.
The magnetic lanthanide sublattice, seen in our refinement of the tetragonal
pyrogermanate crystal structure, is a right-handed spiral of edge-sharing and
corner-sharing triangles; the local Ho-O coordination indicates that the
crystal field is anisotropic. Susceptibility and magnetization data indeed show
that the magnetism is highly anisotropic, and the magnetic structure has the Ho
moments confined to the plane perpendicular to the structural spiral. The
ordered moment of Ho3+, as determined from refinement of the neutron
diffraction data, is 9.0 mu_B. Magnetic ordering occurs around 1.6 K.
Temperature and field dependent ac susceptibility measurements show that this
compound displays spin relaxation phenomena analogous to what is seen in the
spin ice pyrochlore system Ho2Ti2O7.

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The categories of this paper are: econ
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The categories of this paper are: plasm-ph
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The categories of this paper are: dg-ga
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The categories of this paper are: atom-ph
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The categories of this paper are: alg-geom
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The categories of this paper are: nucl-ex
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The categories of this paper are: nucl-th
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The categories of this paper are: bayes-an
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The categories of this paper are: hep-ex
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The categories of this paper are: solv-int
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The categories of this paper are: cs
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The categories of this paper are: cmp-lg
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The categories of this paper are: hep-th
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The categories of this paper are: q-alg
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The categories of this paper are: quant-ph
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The categories of this paper are: gr-qc