Smallest limit of tube diameters for encasing of particular fullerenes determined by radial breathing mode Raman scattering

Lineshapes of radial breathing mode (RBM) Raman scattering from single-wall carbon nanotubes (SWNTs) encasing the fullerenes vary depending on the siz es of fullerenes. The lineshape fit using Lorentzian lines to the spectrum indicates downshift of co, (RBM frequency) for most lines as compared with those observed in empty-SWNTs, except for one upshifted line associating wi th the stress to the tube-wall from the inside fullerenes. The smallest lim it of tube diameters (d) is determined from this upshifted line, and they a re resulting to be similar to1.37 nm for C-60, similar to1.45 nm for both C -76 and C-78, and similar to1.54 nm for C-84 when using omega (r) (cm(-1)) = 246/d (nm). (C) 2001 Published by Elsevier Science B.V.