Raman scattering study of double-wall carbon nanotubes derived from the chains of fullerenes in single-wall carbon nanotubes

Double-wall carbon nanotubes (DWNTs) were prepared in quantitative amount f rom the chains of C-60 molecules generated inside single-wall carbon nanotu bes (SWNTs), The C-60 molecules inside the SWNT unchange up to similar to 8 00 degreesC without dedoping. Further heating at similar to 1200 degreesC i nduces the coalescence between C-60 and eventually the Coo molecules transf orm into a tubular structure. The DWNTs thus prepared show radial breathing mode (RBM) Raman scattering associated with inner tubes as well as those f rom parent outer tubes, which are all explained by a model of diameter pair ing in DWNT with an inner tube diameter smaller by 0.71 +/- 0.05 nm than an outer one. (C) 2001 Elsevier Science B.V. All rights reserved.