Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Single-Molecule Surface-Enhanced Raman Scattering Spectrum of
  Non-Resonant Aromatic Amine Showing Raman Forbidden Bands   We present the experimentally obtained single-molecule (SM) surface-enhanced
Raman scattering (SERS) spectrum of 4-aminibenzenethiol (4-ABT), also known as
para-aminothiophenol (PATP). Measured at a 4-ABT concentration of 8 * 10^-10 M,
the spectra show Raman forbidden modes. The SM-SERS spectrum of 4-ABT obtained
using a non-resonant visible laser is different from the previously reported
SERS spectra of 4-ABT, and could not be reconstructed using quantum mechanical
calculations. Careful classical assignments (not based on quantum-mechanical
calculations) are reported, and indicate that differences in the reported
spectra of 4-ABT are mainly due to the appearance of Raman forbidden bands. The
presence of Raman forbidden bands can be explained by the charge-transfer (CT)
effect of 4-ABT adsorbed on the silver nanostructures, indicating a breakdown
of Raman selection rules at the SERS hotspot.

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The categories of this paper are: nlin
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The categories of this paper are: dg-ga
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The categories of this paper are: chao-dyn
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The categories of this paper are: stat
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The categories of this paper are: math-ph
31
The categories of this paper are: ao-sci
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The categories of this paper are: math
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The categories of this paper are: q-fin
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The categories of this paper are: hep-ph
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The categories of this paper are: alg-geom
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The categories of this paper are: hep-th
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The categories of this paper are: patt-sol
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The categories of this paper are: funct-an
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The categories of this paper are: chem-ph
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The categories of this paper are: bayes-an
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The categories of this paper are: astro-ph