In spite of the appreciable value of the transition dipole moment of the (C=O) vibration in ME6N (4-cyanophenyl-4’-hexylbenzoate) liquid crystal, its NCE (noncoincidence effect) was found very low . We suspected that this was originated by the steric hindrance of the bulky phenyl groups in proximity of the C=O group in ME6N which, acting as intermolecular spacers, may increase the separation between the C=O oscillators in adjacent molecules then reducing the NCE of the corresponding (C=O) Raman band. The results reported in this contribution support this hypothesis.
Steric hindrance effects of phenyl groups on the noncoincidence effect of the nu(C=O) Raman band in molecular liquids / G.Venditti; A.Arcioni;M.G.Giorgini; M.Musso. - STAMPA. - (2006), pp. 93-94. (Intervento presentato al convegno EMLG/JMLG Annual Meeting, Liquid systems under extreme conditions tenutosi a Barcelona, Spain nel 3-7 September 2006).
Steric hindrance effects of phenyl groups on the noncoincidence effect of the nu(C=O) Raman band in molecular liquids
VENDITTI, GIAMPAOLO;ARCIONI, ALBERTO;GIORGINI, MARIA GRAZIA;
2006
Abstract
In spite of the appreciable value of the transition dipole moment of the (C=O) vibration in ME6N (4-cyanophenyl-4’-hexylbenzoate) liquid crystal, its NCE (noncoincidence effect) was found very low . We suspected that this was originated by the steric hindrance of the bulky phenyl groups in proximity of the C=O group in ME6N which, acting as intermolecular spacers, may increase the separation between the C=O oscillators in adjacent molecules then reducing the NCE of the corresponding (C=O) Raman band. The results reported in this contribution support this hypothesis.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
