@article {2526,
	title = {Evolutionary algorithms to solve complicated NMR spectra},
	journal = {Journal of Chemical Physics},
	volume = {130},
	number = {4},
	year = {2009},
	note = {ISI Document Delivery No.: 401TJTimes Cited: 3Cited Reference Count: 37Meerts, W. Leo de Lange, C. A. Weber, A. C. J. Burnell, E. E.},
	month = {Jan},
	pages = {8},
	type = {Article},
	abstract = {The complexity of H-1 NMR spectra of solutes in partially ordered solvents such as liquid crystals increases rapidly with the number of spins. Spectra of simple solutes with sufficient symmetry and containing not too many spins (typically <= 8) are readily analyzed. The analysis of larger spin systems is more difficult, and often impossible. In this paper we present the application of a general automated evolutionary algorithm to solve the highly complex proton NMR spectrum of the 12-spin system pentane, a solute that interconverts rapidly among several symmetry-unrelated conformations. The interpretation of the spectral parameters that are obtained from the analysis requires the use of a model to connect relative orientational orders in symmetry-unrelated conformers.},
	keywords = {ALKYL CHAINS, AUTOMATED-ANALYSIS, evolutionary computation, HIGH-RESOLUTION NMR, liquid crystals, magnetic resonance, MOLECULAR-STRUCTURE, MULTIPLE-QUANTUM SPECTRA, NEMATIC LIQUID-CRYSTALS, ORDER, organic compounds, PROTON, SHAPE, SOLUTES, spectroscopy computing, STRATEGY},
	isbn = {0021-9606},
	url = {<Go to ISI>://000262965000028},
	author = {Meerts, W. L. and de Lange, C. A. and Weber, A. C. J. and Burnell, E. E.}
}
@article {1044,
	title = {NMR measurement of smectic ordering and nematic-smectic-A coupling in a liquid crystal},
	journal = {Chemical Physics Letters},
	volume = {398},
	number = {4-6},
	year = {2004},
	note = {ISI Document Delivery No.: 867OVTimes Cited: 11Cited Reference Count: 31},
	month = {Nov},
	pages = {517-521},
	type = {Article},
	abstract = {The nuclear magnetic resonance (NMR) spectra of three substituted benzenes as solutes in the liquid crystal 8CB were investigated. The orientational order of all solutes was obtained in the nematic and smectic-A phases. A change in temperature dependence of orientational ordering was observed at the nematic to smectic-A phase transition. We analyzed these results via Kobayashi-McMillan theory applied to solutes, i.e. by incorporating smectic-A layering and nematic smectic-A coupling into a mean-field orientational Hamiltonian. By fitting to experiment, we fully determined Hamiltonian prefactors. The nematic smectic coupling, determined for the first time by NMR, appears solute independent. Solute smectic-A order parameters were self-consistently determined. (C) 2004 Published by Elsevier B.V.},
	keywords = {BINARY-MIXTURES, FIELD, NUCLEAR-MAGNETIC-RESONANCE, orientational order, PHASE-TRANSITION, SHAPE, SOLUTES, TEMPERATURE-DEPENDENCE, TRICRITICAL POINT},
	isbn = {0009-2614},
	url = {<Go to ISI>://000224852800044},
	author = {Yethiraj, A. and Sun, Z. M. and Dong, R. Y. and Burnell, E. E.}
}
@article {5219,
	title = {Binding of small alcohols to a lipid bilayer membrane: does the partitioning coefficient express the net affinity?},
	journal = {Biophysical Chemistry},
	volume = {89},
	number = {1},
	year = {2001},
	note = {ISI Document Delivery No.: 397WQTimes Cited: 13Cited Reference Count: 55},
	month = {Jan},
	pages = {53-63},
	type = {Article},
	abstract = {The total vapor pressures at 26 degreesC of binary (water-alcohol) and ternary (water-alcohol-vesicle) systems were measured for sis short chain alcohols. The vesicles were unilamellar dipalmitoyl phosphatidylcholine (DMPC). The data was used to evaluate the effect of vesicles on the chemical potential of alcohols expressed as the preferential binding parameter of the alcohol-lipid interaction, Gamma (23). This quantity is a thermodynamic (model-free) measure of the net strength of membrane-alcohol interactions. For the smaller investigated alcohols (methanol, ethanol and 1-propanol) Gamma (23) was negative. This is indicative of so-called preferential hydration, a condition where the affinity of the membrane for water is higher than the affinity for the alcohol. For the longer alcohols (1-butanol, 1-pentanol, 1-hexanol) Gamma (23) was positive and increasing with increasing chain length. This demonstrates preferential binding, i.e. enrichment of alcohol in the membrane and a concomitant depletion of the solute in the aqueous bulk. The measured values of Gamma (23) were compared to the number of alcohol-membrane contacts specified by partitioning coefficients from the literature. It was found that for the small alcohols the number of alcohol-membrane contacts is much larger than the number of preferentially bound solutes. This discrepancy, which is theoretically expected in cases of very weak binding, becomes less pronounced with increasing alcohol chain length, and when the partitioning coefficient exceeds approximately 3 on the molal scale (10(2) in mole fraction units) it vanishes. Based on this, relationships between structural and thermodynamic interpretations of membrana partitioning are discussed. (C) 2001 Elsevier Science B.V. All rights reserved.},
	keywords = {energy of interaction, ETHANOL, free, lipid membranes, membrane partitioning, MODEL, NONELECTROLYTE PARTITION, PHASE, PHOSPHATIDYLCHOLINE, preferential binding, protein stability, SOLUTES, THERMODYNAMICS, vapor pressure, VAPOR-PRESSURE, WATER},
	isbn = {0301-4622},
	url = {<Go to ISI>://000166721200005},
	author = {Westh, P. and Trandum, C. and Koga,Yoshikata}
}
@article {4944,
	title = {Dipole-induced ordering in nematic liquid crystals. II. The elusive holy grail},
	journal = {Journal of Chemical Physics},
	volume = {113},
	number = {8},
	year = {2000},
	note = {ISI Document Delivery No.: 345AGTimes Cited: 23Cited Reference Count: 47},
	month = {Aug},
	pages = {3452-3465},
	type = {Article},
	abstract = {Similar size and shape molecules with different electric multipoles are used to investigate effects of molecular dipole, quadrupole, and polarizability interactions on the average orientational order of solutes in nematic liquid crystals. Solutes are codissolved in the same sample tube so that the orientational ordering among solutes can be directly compared and analyzed using mean-field models. Permanent dipoles have a negligible influence on solute orientational order. Effects from molecular polarizability interactions could not be separated from short-range interactions. However, order parameters predicted from strong, short-range repulsive forces coupled with interactions between the solute quadrupole and the average electric field gradient felt by the solute are consistent with experimental values. For the nematic mixture 55 wt\% ZLI 1132 in EBBA [N-(pethoxybenzylidene)-p{\textquoteright}-n-butylaniline] the contribution to solute ordering from long-range electrostatic interactions is negligible. (C) 2000 American Institute of Physics. [S0021-9606(00)52232-6].},
	keywords = {AB-INITIO, ELECTRIC-DIPOLE, HARD ELLIPSOIDS, MEAN TORQUE, MOLECULAR QUADRUPOLE-MOMENTS, MONTE-CARLO SIMULATIONS, NMR-SPECTRA, ORDER, ORIENTATIONAL, SOLUTES, SOLVENTS},
	isbn = {0021-9606},
	url = {<Go to ISI>://000088792800063},
	author = {Syvitski, R. T. and Burnell, E. E.}
}
@article {4746,
	title = {Monte Carlo simulations of zero electric field gradient liquid crystal mixtures},
	journal = {Chemical Physics Letters},
	volume = {331},
	number = {5-6},
	year = {2000},
	note = {ISI Document Delivery No.: 382YCTimes Cited: 13Cited Reference Count: 14},
	month = {Dec},
	pages = {455-464},
	type = {Article},
	abstract = {We explore with Monte Carlo simulations the NMR finding that solutes in special nematic liquid crystal mixtures {\textquoteright}feel{\textquoteright} zero average electric field gradient F-ZZ. The simulations involve solute-solvent mixtures of 1000 identical Gay-Berne ellipsoidal particles with added electric quadrupoles of varying strengths placed at particle centres. As long as all quadrupoles are sufficiently small, F-ZZ calculated at the particle centres is equal for all particles. For larger quadrupole moments, interactions among quadrupoles alter the interparticle distribution and subsequently F-ZZ depends on both solvent and solute quadrupoles; in general, the quadrupolar interactions produce a negative contribution to energy. (C) 2000 Elsevier Science B.V. All rights reserved.},
	keywords = {NMR, orientational order, SHAPE, SOLUTES},
	isbn = {0009-2614},
	url = {<Go to ISI>://000165854100016},
	author = {Burnell, E. E. and Berardi, R. and Syvitski, R. T. and Zannoni, C.}
}
@article {4945,
	title = {Multiple quantum and high-resolution NMR, molecular structure, and order parameters of partially oriented ortho and meta dimethyl-, dichloro-, and chloromethylbenzenes codissolved in nematic liquid crystals},
	journal = {Journal of Magnetic Resonance},
	volume = {144},
	number = {1},
	year = {2000},
	note = {ISI Document Delivery No.: 313NCTimes Cited: 18Cited Reference Count: 62},
	month = {May},
	pages = {58-73},
	type = {Article},
	abstract = {We develop a strategy for analyzing complex nuclear magnetic resonance (NMR) spectra of several solutes codissolved in liquid-crystal phases. Spectral parameters of solutes m- or o-xylene were estimated by analyzing 2D multiple-quantum NMR spectra using a modified version of a least-squares fitting routine which adjusts chemical shifts, order parameters, structural parameters, and/or dipolar couplings independently. These estimates were used to facilitate analysis of the high-resolution spectra which contain resonances from many solutes. Calculated spectra of m- or o-xylene were subtracted from the experimental high-resolution spectra leaving resonances from the other solutes readily visible, Accurate spectral parameters of all codissolved solutes were determined from the high-resolution spectra. Order parameters and structural parameters (including vibrationally corrected parameters) of m- and o-xylene, m- and o-chlorotoluene, and m- and o-dichlorobenzene were calculated from the dipolar couplings. (C) 2000 Academic Press.},
	keywords = {ELECTRIC-DIPOLE INTERACTIONS, EXCITATION, INTERNAL-ROTATION, NUCLEAR-MAGNETIC-RESONANCE, orientational order, PHASE, POTENTIALS, SELECTIVE, SOLUTES, SOLVENTS, TRANSITIONS},
	isbn = {1090-7807},
	url = {<Go to ISI>://000087004900008},
	author = {Syvitski, R. T. and Burnell, E. E.}
}
@article {4677,
	title = {Intermolecular potentials in liquid crystals: Comparison between simulations and NMR experiments},
	journal = {International Journal of Modern Physics C},
	volume = {10},
	number = {2-3},
	year = {1999},
	note = {ISI Document Delivery No.: 222HPTimes Cited: 12Cited Reference Count: 21Meeting on Recent Developments in the Computer Simulations of Liquid CrystalsJUN 18, 1998ERICE, ITALY},
	month = {May},
	pages = {403-413},
	type = {Proceedings Paper},
	abstract = {The anisotropic intermolecular forces responsible for the orientational ordering in liquid crystals are probed by comparing Monte Carlo (MC) simulations with experimental nuclear magnetic resonance (NMR) results for solutes in nematic liquid crystals. In a special liquid crystal mixture where all long-range interactions are assumed to be minimized, the models for short-range interactions which best fit NMR experimental solute order parameters also best fit solute order parameters from MC simulations of hard ellipsoids. This is taken as an indication that in this special mixture the intermolecular potential is dominated by short-range forces. However, for liquid crystals where long-range interactions are important, simulations of hard ellipsoids with point quadrupoles cannot reproduce even the gross effects observed with experimental NMR data.},
	keywords = {anisotropic intermolecular force, ELECTRIC-DIPOLE INTERACTIONS, interaction, liquid crystal, MOLECULES, Monte Carlo, MONTE-CARLO SIMULATIONS, NEMATIC SOLVENTS, nuclear magnetic resonance experiment, ORDER, ORIENTATIONAL, quadrupole interaction, SHAPE, SHORT-RANGE, SIMULATION, SIZE, SOLUTES},
	isbn = {0129-1831},
	url = {<Go to ISI>://000081779000007},
	author = {Syvitski, R. T. and Polson, J. M. and Burnell, E. E.}
}
@article {4676,
	title = {NMR and molecular structure of partially oriented mono and para methyl- and chlorobenzenes dissolved in nematic liquid crystals},
	journal = {Canadian Journal of Chemistry-Revue Canadienne De Chimie},
	volume = {77},
	number = {11},
	year = {1999},
	note = {ISI Document Delivery No.: 253FETimes Cited: 8Cited Reference Count: 69},
	month = {Nov},
	pages = {1761-1774},
	type = {Article},
	abstract = {Spectral parameters, order parameters, and structural parameters, including the vibrationally corrected r(alpha) structure of the partially oriented solutes p-xylene, p-chlorotoluene, p-dichlorobenzene, toluene, and chlorobenzene dissolved in three liquid crystal mixtures, are reported. For samples containing the three solutes p-xylene, p-dichlorobenzene, and 1,3,5-trichlorobenzene, multiple quantum (MQ) nuclear magnetic resonance was used to aid in the analysis of the complex high-resolution spectra of the g-xylene. The high-resolution spectra of 1,3,5-trichlorobenzene and p-dichlorobenzene were easily identified and analyzed once the calculated p-xylene spectrum was subtracted from the experimental one. The methyl groups of p-xylene, p-chlorotoluene, and toluene have similar geometries when the structure is determined from dipolar couplings corrected for harmonic vibrations.},
	keywords = {ELECTRIC-DIPOLE INTERACTIONS, EXCITATION, H-2 NMR, MAGNETIC-RESONANCE, MEAN TORQUE, molecular structure, MULTIPLE-QUANTUM NMR, nematic liquid crystal, NMR, ORDER MATRIX, order parameter, SELECTIVE, SOLUTES, SOLVENTS, SPECTRA},
	isbn = {0008-4042},
	url = {<Go to ISI>://000083545300009},
	author = {Syvitski, R. T. and Burnell, E. E.}
}
@article {4114,
	title = {Analysis of single and multiple quantum NMR spectra of 1,3-dichloro-2-ethenylbenzene in liquid crystal solvents},
	journal = {Molecular Physics},
	volume = {90},
	number = {4},
	year = {1997},
	note = {ISI Document Delivery No.: WN909Times Cited: 10Cited Reference Count: 37},
	month = {Mar},
	pages = {541-551},
	type = {Article},
	abstract = {The single and multiple quantum NMR spectra of 1,3-dichloro-2-ethenylbenzene as solute in two different nematic liquid crystals have been measured and analysed in terms of dipolar couplings and chemical shift differences. Because the single quantum spectra did not yield to straightforward analysis, normal and frequency selective multiple quantum experiments were used to aid the analysis. The results from four spectra were combined to yield structural information and the order matrix in each solution. The structure of the ring is very close to that of 1,3-dichlorobenzene, and that of the ethenyl group very close to that of ethenyl-benzene. The dihedral angle between the ethenyl group and the aromatic ring is found to be 454 +/- 1.0 degrees, and the C-CC=C angle is found to be 127.3 +/- 0.3 degrees.},
	keywords = {EQUILIBRIUM, FIELD, MAGNETIC-RESONANCE, MIXTURES, MOLECULAR-STRUCTURE, orientational order, ROTATION, SHAPE, SOLUTES, SPECTROSCOPY},
	isbn = {0026-8976},
	url = {<Go to ISI>://A1997WN90900005},
	author = {Rendell, J. C. T. and Burnell, E. E.}
}
@article {4141,
	title = {Dipole-induced ordering in nematic liquid crystals fact or fiction?},
	journal = {Chemical Physics Letters},
	volume = {281},
	number = {1-3},
	year = {1997},
	note = {ISI Document Delivery No.: YP239Times Cited: 18Cited Reference Count: 35},
	month = {Dec},
	pages = {199-206},
	type = {Article},
	abstract = {Similar size and shape molecules with different electric multipoles are used to investigate effects of dipole and quadrupole interactions on the average orientation of solutes in nematic liquid crystals. Permanent dipoles have a negligible influence on solute orientation. Order parameters predicted from strong, short-range repulsive forces coupled with interactions between the solute quadrupole and the average electric field gradient felt by the solute [EFG] are consistent with experimental values. Calculated [EFG]{\textquoteright}s are the same sign and similar magnitude to those determined previously from D-2 and HD. For the nematic mixture 55wt\% ZLI 1132 in EBBA, the contribution to solute ordering from long-range electrostatic interactions is negligible. (C) 1997 Elsevier Science B.V.},
	keywords = {deuterium, ELECTRIC-DIPOLE, MECHANISMS, MOLECULAR-HYDROGEN, NMR-SPECTRA, orientational order, POTENTIALS, QUADRUPOLE-MOMENTS, SOLUTES, SOLVENTS},
	isbn = {0009-2614},
	url = {<Go to ISI>://000071256600030},
	author = {Syvitski, R. T. and Burnell, E. E.}
}
@article {4115,
	title = {Orientational order of 1,3-dichloro-2-ethenylbenzene in liquid crystal solvents},
	journal = {Canadian Journal of Chemistry-Revue Canadienne De Chimie},
	volume = {75},
	number = {8},
	year = {1997},
	note = {ISI Document Delivery No.: XX043Times Cited: 2Cited Reference Count: 38},
	month = {Aug},
	pages = {1156-1161},
	type = {Article},
	abstract = {The order parameter matrices of a molecule that has no symmetry, 1,3-dichloro-2-ethenylbenzene, dissolved in two different nematic liquid-crystal solvents are analyzed in terms of various models for the intermolecular mean-field potential. In a mixture of liquid crystals for which the interaction between the molecular quadrupole moment tensor and the average electric field gradient of the nematic solvent has been minimized, the orientational order is best described by models for the short-range anisotropic potential. The most successful potentials are written in terms of anisotropic interactions between the solute surface and the liquid-crystal mean field. This represents a strong test of such models because they simultaneously fit the five independent orientational parameters obtained from the same solute, thus removing the problems associated with comparing results among different solutes in either the same or a different sample tube.},
	keywords = {ALKYL CHAINS, ANISOTROPIC, FIELD, INTERMOLECULAR FORCES, liquid crystals, MAGNETIC-RESONANCE, MIXTURES, MOLECULES, NEMATIC SOLVENT, NMR, order parameters, PHASES, SHAPE, SOLUTES},
	isbn = {0008-4042},
	url = {<Go to ISI>://A1997XX04300014},
	author = {Rendell, J. C. T. and Zimmerman, D. S. and vanderEst, A. J. and Burnell, E. E.}
}
@article {3919,
	title = {Tritium nuclear magnetic resonance study of T-2, HT, and DT dissolved in nematic solvents},
	journal = {Physical Review E},
	volume = {55},
	number = {1},
	year = {1997},
	note = {ISI Document Delivery No.: WD545Times Cited: 5Cited Reference Count: 25Part A},
	month = {Jan},
	pages = {496-503},
	type = {Article},
	abstract = {A tritium nuclear magnetic resonance study is carried out on the T-2, HT, and DT isotopomers of dihydrogen dissolved in various nematic phases, including a zero-electric-field-gradient mixture. Ab initio calculations are performed to reproduce the observed dipolar couplings. Within the framework of the {\textquoteright}{\textquoteright}mean-field{\textquoteright}{\textquoteright} approximation, the results provide support for a picture in which two independent contributions to the solute orientation can be distinguished. One contribution involves a liquid-crystal-dependent interaction between the mean solvent electric-field gradient and the solute molecular quadrupole moment. The other contribution is of unknown origin; however, it is essentially identical in all liquid crystals and it can be modeled adequately with a phenomenological mean-field interaction. A remarkable feature of this second interaction is that it causes the average orientation of the asymmetrical isotopomers, and especially of HT, to behave differently from the symmetrical species.},
	keywords = {ELECTRIC-FIELD GRADIENTS, ENVIRONMENTS, LIQUID-CRYSTAL MIXTURES, MECHANISMS, METHANES, MOLECULAR-HYDROGEN, NMR, orientational order, SOLUTES},
	isbn = {1063-651X},
	url = {<Go to ISI>://A1997WD54500062},
	author = {Burnell, E. E. and de Lange, C. A. and Segre, A. L. and Capitani, D. and Angelini, G. and Lilla, G. and Barnhoorn, J. B. S.}
}
@article {3822,
	title = {Micelle-induced change of mechanism in the reaction of muonium with acetone},
	journal = {Canadian Journal of Chemistry-Revue Canadienne De Chimie},
	volume = {74},
	number = {11},
	year = {1996},
	note = {ISI Document Delivery No.: WC124Times Cited: 1Cited Reference Count: 25},
	month = {Nov},
	pages = {1945-1951},
	type = {Article},
	abstract = {Muonium atoms add to the O atom of the carbonyl group of acetone to give the muonated free radical (CH3)(2)C-O-Mu when the reaction takes place in water or hydrocarbons, but not when the acetone is localized in micelles. Micelles have no effect on the formation of muonated cyclohexadienyl radicals when muonium reacts with benzene under similar conditions. The addition reaction with acetone appears to have been subsumed by a faster alternative reaction in the micellar environment. Evidence is presented for this interpretation rather than for an inhibition of the radical or for a shift in the muon level-crossing resonance spectrum with hydrogen (muonium) bonding, though major shifts are seen for the spectrum of this radical in pure solvents of widely different dielectric constant. It is suggested that muonium{\textquoteright}s {\textquoteright}{\textquoteright}abstraction{\textquoteright}{\textquoteright} reaction takes over in micelles because significant micelle-induced enhancement effects were previously observed in that type of reaction. The data are consistent with a I ate constant for the abstraction reaction of muonium with acetone in micelles of >6 x 10(8) M(-1) s(-1).},
	keywords = {AQUEOUS-SOLUTIONS, H/Mu abstraction, H/Mu-addition, HYDROGEN-ATOMS, kinetic isotope effects, LEVEL-CROSSING-RESONANCE, micelle enhancement, muonium, radical formation, SOLUTES, SPECTROSCOPY, WATER},
	isbn = {0008-4042},
	url = {<Go to ISI>://A1996WC12400008},
	author = {Stadlbauer, J. M. and Venkateswaran, K. and Gillis, H. A. and Porter, G. B. and Walker, D. C.}
}
@article {2920,
	title = {THE ORIENTATION OF MOLECULES WITH INTERNAL-ROTATION IN NEMATIC PHASES},
	journal = {Molecular Physics},
	volume = {80},
	number = {1},
	year = {1993},
	note = {ISI Document Delivery No.: LW723Times Cited: 10Cited Reference Count: 33},
	month = {Sep},
	pages = {177-189},
	type = {Article},
	abstract = {The anisotropic couplings obtained from the H-1 nuclear magnetic resonance (NMR) spectra of partially oriented molecules with internal rotation are difficult to analyse because the order parameters for each conformer cannot be deduced without assumptions. The purpose of this paper is to show how a model for the anisotropic short-range potential can be useful in the interpretation of the high-resolution H-1 NMR spectra of the flexible molecules furfural, 2-chlorobenzaldehyde, and 2,2{\textquoteright}-dithiophene dissolved in a 55\% Merck ZLI 1132-45\% N-(p-ethoxybenzylidene)-2,6-dideutero-p{\textquoteright}-n-butylaniline (w/w) mixture. In this nematic mixture there is no contribution to the anisotropic potential from the interaction between the solute molecular quadrupole moment and the average electric field gradient of the liquid crystal solvent; the dominant anisotropic intermolecular potential in this mixture is taken to result solely from short-range interactions. We find good agreement between experiment and the order parameters calculated by the model of short-range interactions. The ratios of order parameters for the s-cis and s-trans conformers predicted by the model are used to calculate the statistical weights of the s-trans conformation for the solutes: at 304 K, p(trans)(furfural) = 0.45 +/- 0.02, p(trans)(2-chlorobenzaldehyde) = 0.901 +/- 0.006 and p(trans)(2,2{\textquoteright}-dithiophene) = 0.6094 +/- 0.0008.},
	keywords = {BARRIER, CONFORMATION, LIQUID-CRYSTALS, ORDER, SIZE, SOLUTES},
	isbn = {0026-8976},
	url = {<Go to ISI>://A1993LW72300013},
	author = {ter Beek, L. C. and Zimmerman, D. S. and Burnell, E. E.}
}
@article {2714,
	title = {ZERO ELECTRIC-FIELD GRADIENT MIXTURES FOR THE ELUCIDATION OF ORIENTATIONAL MECHANISMS},
	journal = {Liquid Crystals},
	volume = {13},
	number = {3},
	year = {1993},
	note = {ISI Document Delivery No.: KX191Times Cited: 22Cited Reference Count: 28},
	month = {Mar},
	pages = {319-343},
	type = {Article},
	abstract = {A novel zero electric field gradient nematic liquid crystal made up from two nematic liquid crystal components is employed as a solvent for a series of molecules ranging from small molecules to mesogens themselves. Nuclear magnetic resonance is used to determine the degree of order of the solute and solvent molecules. Results are compared to those obtained for two completely different zero electric field gradient nematic mixtures. The comparison strongly indicates that for a variety of molecules largely differing in size, shape and flexibility their degree of order can be described by a single orientation mechanism. This mechanism can be adequately modelled by a simple phenomenological mean field model based on the size and shape anisotropy of the dissolved species. The use of zero electric field gradient mixtures in combination with this mean field model allows the prediction of solute order parameters at approximately the 10 per cent level.},
	keywords = {ANISOTROPIC ENVIRONMENTS, METHANES, MOLECULES, NEMATIC LIQUID-CRYSTALS, NMR, ORDER, SIZE, SOLUTES, SOLVENTS},
	isbn = {0267-8292},
	url = {<Go to ISI>://A1993KX19100001},
	author = {Barnhoorn, J. B. S. and de Lange, C. A. and Burnell, E. E.}
}
@article {7119,
	title = {THE CONFORMATION OF 2,2{\textquoteright}-DITHIOPHENE IN NEMATIC SOLVENTS DETERMINED BY H-1-NMR},
	journal = {Molecular Physics},
	volume = {74},
	number = {5},
	year = {1991},
	note = {ISI Document Delivery No.: GY085Times Cited: 24Cited Reference Count: 26},
	month = {Dec},
	pages = {1027-1035},
	type = {Article},
	abstract = {In this paper we report a determination of the structure 2,2{\textquoteright}-dithiophene dissolved in different nematic liquid crystal solvents. The H-1-NMR spectra of this molecule dissolved in a 55\% Merck ZLI 1132/45\% N-(4-ethoxybenzylidene)-4{\textquoteright}-n-butylaniline (w/w) mixture are recorded at 300 and 304 K and are analysed. The dipolar coupling constants obtained are used to show that the solute molecule exists in both the s-cis and the s-trans conformations. The s-trans conformer is planar and the absolute value of the dihedral angle-PHI between the two thiophene ring planes for the s-cis conformer is found to be (24 +/- 1)degrees. Using the same method of analysis we reinterpreted two additional independent sets of published dipolar coupling constants from H-1-NMR spectra of 2,2{\textquoteright}-dithiophene dissolved in Merck Phase IV at room temperature and in 80\% N-(4-ethoxybenzylidene)-4{\textquoteright}-n-butylaniline/20\% O-carbobutoxy-4-oxybenzoic acid ethoxy phenyl ester at 301 K. These additional studies yield the same results for the structure of 2,2{\textquoteright}-dithiophene. We also estimate that in each of the three nematic solvents (61 +/- 3)\% of the solute 2,2{\textquoteright}-dithiophene exists in the s-trans state.},
	keywords = {2, 2{\textquoteright}-BITHIENYL, BARRIER, LIQUID-CRYSTALS, MOLECULES, orientational order, PHASE, SIZE, SOLUTES},
	isbn = {0026-8976},
	url = {<Go to ISI>://A1991GY08500007},
	author = {ter Beek, L. C. and Zimmerman, D. S. and Burnell, E. E.}
}
