2H NMR spectroscopy is employed to investigate the orientational order, molecular structure and phase transitions of the chiral smectic liquid crystal (S)-[4-(2- methylbutyl)phenyl]-4′-octylbiphenyl carboxylate (8BEF5), partially deuterated in both the chiral chain and the phenyl moiety. 8BEF5 shows a rich polymorphism; the following phases have been observed: Blue phase, N* SmA, SmC*, SmI*, SmF*, SmJ* and SmG* phases. The tilt angle and the orientational order of the phenyl fragment has been investigated throughout the mesophasic range; the additive potential method has been applied in the SmA phase in order to obtain the order parameter of the "average" conformer of the whole molecule.
2H NMR spectroscopy of liquid crystals: structure and orientational order of a chiral smectogen as a model compound of side-group LC polymers
CATALANO, DONATA INES MARIA;DOMENICI, VALENTINA;GEPPI, MARCO;VERACINI, CARLO ALBERTO;
2002-01-01
Abstract
2H NMR spectroscopy is employed to investigate the orientational order, molecular structure and phase transitions of the chiral smectic liquid crystal (S)-[4-(2- methylbutyl)phenyl]-4′-octylbiphenyl carboxylate (8BEF5), partially deuterated in both the chiral chain and the phenyl moiety. 8BEF5 shows a rich polymorphism; the following phases have been observed: Blue phase, N* SmA, SmC*, SmI*, SmF*, SmJ* and SmG* phases. The tilt angle and the orientational order of the phenyl fragment has been investigated throughout the mesophasic range; the additive potential method has been applied in the SmA phase in order to obtain the order parameter of the "average" conformer of the whole molecule.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
