Abstract
Polarized Raman spectra of single-walled BC3 nanotubes(SBCNTs) are calculated as a function of their diameter, chirality, length,and bundle size using a classical force field combined with the bondpolarizabilitymodel. For isolated infinite tubes, we give a mathematicalmodel to estimate their diameter from their Raman spectra. Thetangential modes are sensitive to the tube chirality. The length shorteningof the tube below ∼50 nm leads to the appearance of several additionalRaman lines in the regions of breathing modes and tangential modes. ForSBCNT bundles, the position of the radial breathing mode is significantlyupshifted with respect to its position in isolated SBCNTs, and a specificbundle breathing-like mode is observed below 300 cm−1.