Fantini C, Jorio A, Souza M, Strano M S, Dresselhaus M S, Pimenta M A
Departamento de Física, Universidade Federal de Minas Gerais, Belo Horizonte, MG, 30123-970 Brazil.
Phys Rev Lett. 2004 Oct 1;93(14):147406. doi: 10.1103/PhysRevLett.93.147406. Epub 2004 Sep 29.
This Letter reports the laser energy dependence of the Stokes and anti-Stokes Raman spectra of carbon nanotubes dispersed in aqueous solution and within solid bundles, in the energy range 1.52-2.71 eV. The electronic transition energies (E(ii)) and the radial breathing mode frequencies (omega(RBM)) are obtained for 46 different (18 metallic and 28 semiconducting) nanotubes, and the (n,m) assignment is discussed based on the observation of geometrical patterns for E(ii) versus omega(RBM) graphs. Only the low energy component of the E(M)(11) value is observed from each metallic nanotube. For a given nanotube, the resonant window is broadened and down-shifted for single wall carbon nanotube (SWNT) bundles compared to SWNTs in solution, while by increasing the temperature, the E(S)(22) energies are redshifted for S1 [(2n+m) mod 3=1] nanotubes and blueshifted for S2 [(2n+m) mod 3=2] nanotubes.
本信函报道了分散于水溶液及固体管束中的碳纳米管在1.52 - 2.71 eV能量范围内的斯托克斯和反斯托克斯拉曼光谱的激光能量依赖性。对46种不同的（18种金属性和28种半导体性）纳米管获得了电子跃迁能量（E(ii)）和径向呼吸模式频率（ω(RBM)），并基于E(ii)对ω(RBM)图的几何图案观测讨论了(n,m)归属。从每个金属性纳米管仅观察到E(M)(11)值的低能量成分。对于给定的纳米管，与溶液中的单壁碳纳米管（SWNT）相比，SWNT管束的共振窗口变宽并向下移动，而通过升高温度，对于S1 [(2n + m) mod 3 = 1]纳米管，E(S)(22)能量发生红移，对于S2 [(2n + m) mod 3 = 2]纳米管，E(S)(22)能量发生蓝移。
