Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Trimeron-phonon coupling in magnetite   Using density functional theory, we study the lattice dynamical properties of
magnetite (Fe$_3$O$_4$) in the high-temperature cubic and low-temperature
monoclinic phases. The calculated phonon dispersion curves and phonon density
of states are compared with the available experimental data obtained by
inelastic neutron, inelastic x-ray, and nuclear inelastic scattering. We find a
very good agreement between the theoretical and experimental results for the
monoclinic $Cc$ structure revealing the strong coupling between charge-orbital
(trimeron) order and specific phonon modes. For the cubic phase, clear
discrepancies arise which, remarkably, can be understood assuming that the
strong trimeron-phonon coupling can be extended above the Verwey transition,
with lattice dynamics influenced by the short-range trimeron order instead of
the average cubic structure. Our results establish the validity of trimerons
(and trimeron-phonon coupling) in explaining the physics of magnetite much
beyond their original formulation.

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The categories of this paper are: atom-ph
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The categories of this paper are: patt-sol
2
The categories of this paper are: math
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The categories of this paper are: plasm-ph
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The categories of this paper are: nucl-ex
6
The categories of this paper are: astro-ph
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The categories of this paper are: chao-dyn
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The categories of this paper are: acc-phys
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The categories of this paper are: eess
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The categories of this paper are: nlin
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The categories of this paper are: hep-lat
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The categories of this paper are: stat
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The categories of this paper are: funct-an
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The categories of this paper are: econ
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The categories of this paper are: mtrl-th
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The categories of this paper are: cmp-lg