Ferroelectric Liquid Crystals Induced by Atropisomeric Biphenyl Dopants:  Dependence of the Polarization Power on the Nature of the Symmetry-Breaking Groups

Vizitiu, Despina; Lazar, Carmen; Radke, Joshua P.; Hartley, C. Scott; Glaser, Matthew A.; Lemieux, Robert P.

doi:10.1021/cm000753k

Cited by 27 publications

(43 citation statements)

References 18 publications

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“…This once more prove that in phenyl benzoates the benzene ring in benzoyl part of the ester is coplanar with the carbonyl bond plane while the aromatic plane in the phenoxy part is twisted nearly perpendicular relative to the carboxyl bond plane 13,[77][78][79][80][81] . In contrast to this for phenyl benzo- ate and benzoates with ortho substituents in phenoxy moiety nearly planar conformers were proved as well [82][83][84] . The primary condition for the resonance interaction between two groups is the mutual coplanarity of these groups.…”

Section: Influence Of Para and Meta Substituentsmentioning

confidence: 70%

17O NMR study of ortho and alkyl substituent effects in substituted phenyl and alkyl esters of benzoic acids

Nummert¹,

Mäemets²,

Piirsalu³

et al. 2011

Collect. Czech. Chem. Commun.

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17 O NMR spectra for 44 ortho-, meta-and para-substituted phenyl and alkyl benzoates (C 6 H 5 CO 2 C 6 H 4 -X, C 6 H 5 CO 2 R) at natural abundance in acetonitrile were recorded. Substituent effects on the 17 O NMR chemical shifts, δ( 17 O), of the carbonyl oxygen and the single-bonded phenoxy (OPh) and alkoxy (OR) oxygens have been studied. The δ( 17 O) values of the carbonyl oxygen for para derivatives showed a good correlation with the σ°con-stants. The δ( 17 O) values of carbonyl oxygen for ortho derivatives were found to be described well with the Charton equation containing the inductive, σ I , resonance, σ°R, and steric, E s B , substituent constants in case the data treatment was performed separately for electrondonating +R and electron-attracting -R substituents. The electron-donating +R ortho and para substituents in substituted benzoates caused shielding and the electron-withdrawing -R substituents produced deshielding of the O signal. The steric interaction of ortho substituents with the ester group decreased the electron density at the carbonyl oxygen. In alkyl benzoates the δ( 17 O) values were found to be described well with the inductive, σ I , and the steric, E s B , substituent constants.We have previously investigated the contribution of the inductive, resonance and steric effects of ortho, meta, para and alkyl substituents into the rates of the alkaline hydrolysis in various media (as shown in refs 1-11 ), the carbonyl carbon 13 C NMR chemical shifts 12 , δ CO , and the infrared stretching frequencies of the carbonyl group 13 , ν CO , in substituted phenyl benzoates, X-C 6 H 4 CO 2 C 6 H 5 , C 6 H 5 CO 2 C 6 H 4 -X, and alkyl benzoates, C 6 H 5 CO 2 R. In the recent paper 14 we studied the ortho substituent effect on the 17 O NMR chemical shifts, δ( 17 O), of the carbonyl oxygen and the

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Section: Influence Of Para and Meta Substituentsmentioning

confidence: 70%

17O NMR study of ortho and alkyl substituent effects in substituted phenyl and alkyl esters of benzoic acids

Nummert¹,

Mäemets²,

Piirsalu³

et al. 2011

Collect. Czech. Chem. Commun.

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“…Real molecules with similar structure (i.e. with a pair of almost orthogonal transverse dipoles) have recently been synthesised by Lemieux et al (18)(19)(20)(21) and used as chiral dopants to induce polarisation in an achiral SmC host.…”

Section: Molecular Model Of the Ferroelectric Smc* Phase Based On Dipmentioning

confidence: 99%

Microscopic origin of ferroelectricity in chiral smectic C* liquid crystals and ordering of ‘ferroelectric fishes’ proposed by de Gennes

Osipov¹,

Gorkunov²

2009

Liquid Crystals

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The qualitative microscopic mechanism of ferroelectric ordering in smectic C* liquid crystals originally proposed by de Gennes and others is analysed in detail using the molecular-statistical approach. The general expression is obtained for the spontaneous polarisation of the smectic C* phase composed of chiral and polar molecules of the C 2 symmetry. The polarisation is shown to be determined by molecular chirality, molecular transverse dipole and the non-polar biaxial order parameter which does not vanish in the non-chiral smectic C phase. A particular molecular model is considered in which molecular chirality and molecular biaxiality are determined by the pair of off-centre transverse molecular dipoles. In the context of this model the spontaneous polarisation is evaluated both analytically and numerically.

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“…Phenylazines have been the subject of many experimental [1][2][3][4][5] and semi-empiri cal quantum-mechanical [6][7][8][9][10] investigations in view of the considerable interest of organic bases in several fields of physical and chemical technology (for example homogenous catalysis or liquid crystal and dye laser technology) [11][12][13]. Phenylpyridines are important intermediates in synthesis of drugs, agrochemicals, herbicides, insecticides, desiccants, surfactant agents and anti-inflammatory agents [14].…”

Section: Introductionmentioning

confidence: 99%

Torsional barriers and nonlinear optical properties of 2-, 3-, 4-phenylpyridine molecules

et al. 2006

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The torsional barriers and nonlinear optical properties for all phenylpyridine molecules were calculated by using Hartree-Fock (HF) theory and Becke three-parameter functional (B3LYP) hybrid approaches within the density functional theory framework with the 6-31-H-G(d, p) basis set, and via the GAUSSIAN 98W. The torsional barrier computations show that dihedral angle between the two rings increases with the number of H-H vicinal interactions and torsional barriers with dihedral angles for 3-, 4-phenylpyridines are too similar for both HF and B3LYP level calculations. Also, HOMO-LUMO energy gaps, polarizabilities, anisotropy of polarizabilities, and static hyperpolarizabilities are calculated as a function of dihedral angle between benzene and pyridine rings. The study reveals that the phenylpyridines show very low nonlinear optical properties. The calculated torsional barrier, equilibrium dihedral angle and molecular dipole moment results for these molecules were compared with available experimental and other results determining from different computational methods. : 31.15.Ar, 33.15.Hp, 33.15.Kr PACS

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Ferroelectric Liquid Crystals Induced by Atropisomeric Biphenyl Dopants: Dependence of the Polarization Power on the Nature of the Symmetry-Breaking Groups

Cited by 27 publications

References 18 publications

17O NMR study of ortho and alkyl substituent effects in substituted phenyl and alkyl esters of benzoic acids

17O NMR study of ortho and alkyl substituent effects in substituted phenyl and alkyl esters of benzoic acids

Microscopic origin of ferroelectricity in chiral smectic C* liquid crystals and ordering of ‘ferroelectric fishes’ proposed by de Gennes

Torsional barriers and nonlinear optical properties of 2-, 3-, 4-phenylpyridine molecules

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