TY - JOUR

T1 - Infrared and Raman active vibrational modes in MoS2-based nanotubes

T2 - Symmetry analysis and first-principles calculations

AU - Evarestov, Robert A.

AU - Bandura, Andrei V.

PY - 2018/10/5

Y1 - 2018/10/5

N2 - The possibility to use the axial point group dynamical representations for the infrared and Raman active modes classification in nanotubes is analyzed. The method proposed allows one to obtain the results of phonon symmetry analysis for nanotubes in Mulliken designations, which are traditional for molecules and crystallographic point groups. The approach suggested is applied to the phonon symmetry analysis in the single-wall carbon and MoS2-based nanotubes. First-principles calculations of phonons in a bulk MoS2 crystal and a monolayer S-Mo-S are made. The results obtained are in reasonable agreement with the existing experimental data and other published results. The first-principles calculations of the phonon frequencies for armchair and zigzag MoS2 nanotubes are performed for the first time. It is shown that the number of infrared and Raman active modes becomes fixed starting from the relatively small nanotube diameters. The correlation of the phonon modes of MoS2 nanotubes with diameters up to 3.64 nm with phonon modes of the S-Mo-S monolayer is analyzed. It is demonstrated that the interpretation of the nature of nanotube A-type modes in the crystallographic factorization of the line group L = TF is the same as for m = 0 modes in the “polymer type” factorization L = ZP where P is the subgroup of the isogonal point group F, T is the translation subgroup of line group and the cyclic group Z includes the one-dimensional translations and the rotations around the screw axes or the reflections in the glide planes.

AB - The possibility to use the axial point group dynamical representations for the infrared and Raman active modes classification in nanotubes is analyzed. The method proposed allows one to obtain the results of phonon symmetry analysis for nanotubes in Mulliken designations, which are traditional for molecules and crystallographic point groups. The approach suggested is applied to the phonon symmetry analysis in the single-wall carbon and MoS2-based nanotubes. First-principles calculations of phonons in a bulk MoS2 crystal and a monolayer S-Mo-S are made. The results obtained are in reasonable agreement with the existing experimental data and other published results. The first-principles calculations of the phonon frequencies for armchair and zigzag MoS2 nanotubes are performed for the first time. It is shown that the number of infrared and Raman active modes becomes fixed starting from the relatively small nanotube diameters. The correlation of the phonon modes of MoS2 nanotubes with diameters up to 3.64 nm with phonon modes of the S-Mo-S monolayer is analyzed. It is demonstrated that the interpretation of the nature of nanotube A-type modes in the crystallographic factorization of the line group L = TF is the same as for m = 0 modes in the “polymer type” factorization L = ZP where P is the subgroup of the isogonal point group F, T is the translation subgroup of line group and the cyclic group Z includes the one-dimensional translations and the rotations around the screw axes or the reflections in the glide planes.

KW - axial point group irreducible representations

KW - carbon nanotubes

KW - HSE0 exchange-correlation functional

KW - line symmetry groups

KW - MoS monolayer

KW - MoS nanotubes

KW - phonon frequencies

KW - vibrational modes

UR - http://www.scopus.com/inward/record.url?scp=85054916082&partnerID=8YFLogxK

U2 - 10.1002/jcc.25530

DO - 10.1002/jcc.25530

M3 - Article

C2 - 30318757

AN - SCOPUS:85054916082

VL - 39

SP - 2163

EP - 2172

JO - Journal of Computational Chemistry

JF - Journal of Computational Chemistry

SN - 0192-8651

IS - 26

ER -