Polymorphism and phonon dynamics of alpha-quaterthiophene.
Low-frequency (10-150 cm(-1)) Raman spectra of the low-temperature (LT) and high-temperature (HT) polymorphs of the organic semiconductor alpha-quaterthiophene at 300 and 10 K are reported. Polarized spectra, assisted by quasi-harmonic lattice dynamics (QHLD) calculations, allow characterization of the lattice phonon dynamics and identification of the two phases spectroscopically. The experimental data can be explained by taking into account the coupling between intermolecular (lattice) and low-frequency intramolecular modes. Finally, Raman mapping is used to investigate the phase purity.
Ranzieri
Paolo
P
Dip. Chimica G.I.A.F. and INSTM-UdR Parma, Università di Parma, 43100 Parma, Italy.
Girlando
Alberto
A
Tavazzi
Silvia
S
Campione
Marcello
M
Raimondo
Luisa
L
Bilotti
Ivano
I
Brillante
Aldo
A
Della Valle
Raffaele G
RG
Venuti
Elisabetta
E