Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Polymorphism, phonon dynamics and carrier-phonon coupling in pentacene   The crystal structure and phonon dynamics of pentacene is computed with the
Quasi Harmonic Lattice Dynamics (QHLD) method, based on atom-atom potential. We
show that two crystalline phases of pentacene exist, rather similar in
thermodynamic stability and in molecular density. The two phases can be easily
distinguished by Raman spectroscopy in the 10-100 cm-1 spectral region. We have
not found any temperature induced phase transition, whereas a sluggish phase
change to the denser phase is induced by pressure. The bandwidths of the two
phases are slightly different. The charge carrier coupling to low-frequency
phonons is calculated.

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The categories of this paper are: astro-ph
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The categories of this paper are: hep-ph
1
The categories of this paper are: cs
36
The categories of this paper are: cmp-lg
13
The categories of this paper are: quant-ph
20
The categories of this paper are: acc-phys
28
The categories of this paper are: alg-geom
31
The categories of this paper are: ao-sci
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The categories of this paper are: hep-th
24
The categories of this paper are: dg-ga
30
The categories of this paper are: q-alg
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The categories of this paper are: nlin
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The categories of this paper are: patt-sol
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The categories of this paper are: nucl-ex
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The categories of this paper are: solv-int
29
The categories of this paper are: funct-an