Resonance Raman Optical Activity Spectra of Single-Walled Carbon Nanotube Enantiomers
Martin Magg, Yara Kadria-Vili, Patric Oulevey, R. Bruce Weisman, Thomas Bürgi
Journal Physical Chemistry Letters
We present experimental Raman optical activity (ROA) spectra of enantio-enriched single-walled carbon nanotubes (SWCNTs). Enantiomeric samples of (6,5) SWCNTs were prepared using nonlinear density gradient ultracentrifugation (DGU). Upon excitation at 2.33 eV, remarkably strong G-band signals are obtained due to strong resonance enhancement with the E22Stransition of (6,5) SWCNTs. Enhancement allows measuring the vibrational optical activity (VOA) at unusually low concentrations. The obtained results are in good agreement with the single-excited-state theory (SES). To our knowledge, these are the first experimental VOA spectra of SWCNTs.
Circular dichroism, Nanostructures, Materials