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arXiv · 1610.08270

Single-Molecule Surface-Enhanced Raman Scattering Spectrum of Non-Resonant Aromatic Amine Showing Raman Forbidden Bands

Yuko S. Yamamoto·Yuya Kayano·Yukihiro Ozaki·Zhenglong Zhang·Tomomi Kozu·Tamitake Itoh·Shunsuke Nakanishi
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Abstract

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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Yuko S. Yamamoto, Yuya Kayano, Yukihiro Ozaki, Zhenglong Zhang, Tomomi Kozu, Tamitake Itoh, Shunsuke Nakanishi. 2016-10-26. Single-Molecule Surface-Enhanced Raman Scattering Spectrum of Non-Resonant Aromatic Amine Showing Raman Forbidden Bands. https://arxiv.org/abs/1610.08270

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