Assignment of the Fine Structure in the Optical Absorption Spectra of Soluble Single-Walled Carbon Nanotubes

摘要: Raw electric-arc-produced single-walled carbon nanotubes (SWNTs) were dispersed in organic solvents via a three-step wet chemistry procedure. The soluble sample was purified by continuous dispersion−centrifugation cycles and well-separated SWNTs with high purity successfully obtained, which enable us to test the separated tube properties make comparisons theoretical predictions. Optical absorption experiments on such prepared samples yield fine structures. A series of optical absorptions including some unobserved previous works are identified. On basis electronic band theory, all spectral features systematically assigned transitions between pairs van Hove singularities semiconducting and/or metallic SWNTs. Detailed analysis Raman scattering data reveals that preferentially formed seven discrete diameters chirality close armchair direction, chiral indices (n, ...