The Raman spectroscopic noncoincidence effect (NCE) of the (C=O) band of the liquid crystal ME6N (4-cyanophenyl-4’-hexylbenzoate) has been measured at different temperatures (47-52 °C) around the N-I phase transition (47.8 °C) thanks to a micro-Raman experiment under confocal conditions performed on a homogeneously aligned thin sample. The low value of NCE (0.9 cm-1) obtained in the whole temperature range suggests that the orientational structure of the liquid crystal in both phases is governed by the steric hindrances in proximity of the carbonyl group, rather than by dipolar interactions.
M.G.Giorgini, A.Arcioni, G.Venditti, M.Musso (2007). The Raman noncoincidence effect of the n(C=O) band of the ME6N liquid crystal across the nematic-isotropic phase transition studied by a micro-spectroscopy experiment. JOURNAL OF RAMAN SPECTROSCOPY, 38, 78-86 [10.1002/jrs.1617].
The Raman noncoincidence effect of the n(C=O) band of the ME6N liquid crystal across the nematic-isotropic phase transition studied by a micro-spectroscopy experiment
GIORGINI, MARIA GRAZIA;ARCIONI, ALBERTO;VENDITTI, GIAMPAOLO;
2007
Abstract
The Raman spectroscopic noncoincidence effect (NCE) of the (C=O) band of the liquid crystal ME6N (4-cyanophenyl-4’-hexylbenzoate) has been measured at different temperatures (47-52 °C) around the N-I phase transition (47.8 °C) thanks to a micro-Raman experiment under confocal conditions performed on a homogeneously aligned thin sample. The low value of NCE (0.9 cm-1) obtained in the whole temperature range suggests that the orientational structure of the liquid crystal in both phases is governed by the steric hindrances in proximity of the carbonyl group, rather than by dipolar interactions.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
