Figure 4.

Optical characterization of fractions obtained from the semiconducting C₁₆H₃₄@EA parent. (a) Photoluminescence excitation (PLE) map and (b) radial breathing mode (RBM) resonance Raman maps constructed from spectra at 20 different excitation energies. A dashed line indicates excitation via S₂₂, S₃₃, or S₄₄ in the PLE maps and divides energy ranges where the resonance of S₄₄, S₃₃, and M₁₁ is expected in the Raman maps. The cyan (S₄₄) and magenta (S₃₃) open circles and yellow (M₁₁) open squares are from the Kataura plot and indicate the transition energy as a function of tube diameter. A solid circle indicates the expected Raman shift for the (n,m) species displayed.