Fourier transform Raman and DFT study of three annulated oligothiophenes with different molecular shapes.
Herein, we study the conjugation properties of three different thienoacenes, each of which has three or four fused thiophene rings, by means of Fourier transform Raman spectroscopy. The B3LYP/6-31G** vibrational analysis of all of the collected spectroscopic data evidences that the selective enhancement of a limited number of Raman scatterings is related to the occurrence in the three thienoacenes of a vibronic coupling between the lowest unoccupied frontier molecular orbital (LUMO) and some Raman-active skeletal nu(C==C) stretching modes of 1600-1300 cm(-1).
Malavé Osuna
Reyes
R
Department of Physical Chemistry, University of Málaga, 29071 Málaga, Spain.
Ponce Ortiz
Rocio
R
Ruiz Delgado
Mari Carmen
MC
Nenajdenko
Valentin G
VG
Sumerin
Viktor V
VV
Balenkova
Elizabeth S
ES
Hernández
Víctor
V
López Navarrete
Juan Teodomiro
JT