Electronic International Standard Serial Number (EISSN)
We use 40 laser excitation energies to analyze the differences in the Raman spectra from chemical vapor deposition-derived double-wall carbon nanotube (CVD-DWNT) bundles, fullerene-derived DWNT bundles (C60-DWNTs), and individual fullerene-derived DWNTs with inner type-I and type-II semiconducting tubes paired with outer metallic tubes. For the radial breathing mode (RBM) of SWNTs, an experimental omegaRBM vs dt relationship of the form omegaRBM=A/dt+;I/I; is obtained for the inner tubes of DWNT bundles where the A and ;I/I; constants are found to be close to those obtained by elasticity theory when modeling the elastic properties of graphite. A similar change in omegaRBM is observed for an inner type-II semiconducting (6,5) tube and a type-I (9,1) tube when inside various metallic outer tubes. The G-band frequency is observed to upshift when switching the laser resonance from DWNTs with semiconducting inner tubes to DWNTs with metallic inner tubes. Finally, we measure the G′ feature from C60-DWNTs and note a downshift in frequency with respect to that of CVD-DWNTs.