The assignment of the chiral indices n_1 and n_2 in semiconducting and metallic nanotubes was performed comparing resonance Raman profiles and transition energies in a 3~(rd)-order Kataura plot. We find several complete branches in the Kataura plot and are able to assign the resonance peaks to n_1 and n_2 without prior assumptions about the constant of proportionality between the radial-breathing mode frequency ω_(RBM) and the inverse diameter of the tube. We point out systematic differences in the transition energies and intensities in +1 and –1 nanotube families.
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