Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Charge-transfer excitons in strongly coupled organic semiconductors   Time-resolved and temperature-dependent photoluminescence measurements on
one-dimensional sexithiophene lattices reveal intrinsic branching of
photoexcitations to two distinct species: self-trapped excitons and dark
charge-transfer excitons (CTX; > 5% yield), with radii spanning 2-3 sites. The
significant CTX yield results from the strong charge-transfer character of the
Frenkel exciton band due to the large free exciton bandwidth (~400 meV) in
these supramolecular nanostructures.

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The categories of this paper are: astro-ph
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The categories of this paper are: hep-ex
18
The categories of this paper are: econ
32
The categories of this paper are: atom-ph
30
The categories of this paper are: q-alg
34
The categories of this paper are: chem-ph
33
The categories of this paper are: plasm-ph
22
The categories of this paper are: chao-dyn
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The categories of this paper are: physics
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The categories of this paper are: quant-ph
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The categories of this paper are: q-bio
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The categories of this paper are: hep-th
29
The categories of this paper are: funct-an
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The categories of this paper are: cmp-lg
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The categories of this paper are: q-fin
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The categories of this paper are: solv-int