Chiral angle dependence of resonance window widths in (2n+m) families of single-walled carbon nanotubes

Raman spectra of isolated single-walled carbon nanotubes (SWNTs) were obtained for a wide range of laser excitation energies to study the resonance excitation window of the radial breathing mode feature for members of (2n+m) families. A chiral angle (θ) dependence of the resonance window width () was observed, which is much stronger than the diameter dependence. The implications of this work on nanotube metrology are discussed. © 2010 American Institute of Physics.