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Updated: Jul 26, 2026

Resonance Raman Spectroscopy of Extreme Nanowires and Other 1D Systems
Published on: April 28, 2016
Diminished band-gap transitions of single-walled carbon nanotubes in complexation with aromatic molecules
K A Shiral Fernando1, Yi Lin, Wei Wang
1Department of Chemistry, Howard L. Hunter Chemistry Laboratory, Clemson University, Clemson, SC 29634-0973, USA.
Abstract:
The near-IR absorption spectrum of semiconducting single-walled carbon nanotubes is characterized by the transitions associated with the first (S11) and second (S22) pairs of van Hove singularities in the electronic density of states. We report that a significant effect on the transitions can be caused by non-covalent complexation of the nanotube with planar aromatic molecules such as pyrenes in solution, resulting in the absence of S11 and S22 bands in the near-IR absorption spectrum. Since the complexation is reversible, the characteristic absorption bands can be turned on and off with the complexation in a reversible fashion.
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