2002/12/23 by T. Yu. Astakhova, Astakhova, T. Yu., G. A. Vinogradov +1
Physics and Astronomy · #FOS: Physical sciences #Materials Science (cond-mat.mtrl-sci) #Mesoscale and Nanoscale Physics (cond-mat.mes-hall) #cond-mat.mes-hall #cond-mat.mtrl-sci
paper · pdf · doi:10.48550/arxiv.cond-mat/0212565
18 pages, 9 figures, 3 tables
arxiv created 2002/12/23 · arxiv updated 2009/11/30
In this paper we present the results on Raman-active modes calculation in achiral (n,n) and (n,0) carbon nanotubes (CNTs). vibrational spectra are derived as the eigenvalues of corresponding dynamical matrix at the Γ-point of Brillouin zone. Diagonal components and αxy (=αyx) are the only non-zero components of polarization tensor. Selection rules for Raman-active modes are determined by direct estimations of matrix elements responsible for the intensities of corresponding vibrational transitions. Few E2g modes can be non-Raman-active because of their ``fine'' vibrational structure. We claim that numbers of Raman-active modes for achiral CNTs are: 5 ((n,n) and (n,0), n-even); 6 ((n,n), n-odd); 8 ((n,0), n-odd).