@article {2615,
	title = {Orientational order of near D-3h solutes in nematic liquid crystals. II. Description via Gay-Berne model with embedded quadrupoles},
	journal = {Journal of Chemical Physics},
	volume = {130},
	number = {15},
	year = {2009},
	note = {ISI Document Delivery No.: 437KLTimes Cited: 3Cited Reference Count: 19Sokolovskii, R. O. Burnell, E. Elliott},
	month = {Apr},
	pages = {6},
	type = {Article},
	abstract = {We perform Monte Carlo simulations of a mixture of soft ellipsoids with embedded quadrupoles as a model of various chloro- and methyl-substituted benzenes dissolved in nematic liquid crystals. We find that oblate Gay-Berne ellipsoids with multiple embedded quadrupoles qualitatively reproduce the trend in the order parameter asymmetry experimentally observed in NMR spectra. The trend is opposite to what is expected on the basis of the interaction of the solute{\textquoteright}s quadrupole with the solvent{\textquoteright}s average electric field gradient "felt" by dissolved dihydrogen molecules. We identify the specific minimum of the solute-solvent interaction energy landscape that may produce the unexpected sign of the order parameter asymmetry that is seen in the experiment and the simulation.},
	keywords = {COMPOUNDS, deuterium, dissolving, ELECTRIC-DIPOLE INTERACTIONS, LIQUID MIXTURES, liquid theory, METHODS, Monte Carlo, MONTE-CARLO SIMULATIONS, nematic liquid crystals, nuclear magnetic resonance, ORGANIC, POTENTIALS, SHAPE, SOLVENTS},
	isbn = {0021-9606},
	url = {<Go to ISI>://000265486300033},
	author = {Sokolovskii, R. O. and Burnell, E. E.}
}
@article {2026,
	title = {Mechanisms of solute orientational order in nematic liquid crystals},
	journal = {Journal of Chemical Physics},
	volume = {128},
	number = {16},
	year = {2008},
	note = {ISI Document Delivery No.: 295DXTimes Cited: 7Cited Reference Count: 51Burnell, E. Elliott ter Beek, Leon C. Sun, Zhengmin},
	month = {Apr},
	pages = {10},
	type = {Article},
	abstract = {The order parameters of a number of different solutes dissolved in a number of different nematic liquid-crystal solvents are measured and compared. It is shown that the order parameters can all be rationalized with the ansatz that there exist two independent ordering mechanisms operating in the liquid crystals employed. With this ansatz it is possible to fit the experimental order parameters to better than 5\%. This opens the possibility of the accurate prediction of order parameters in ordered liquids. (c) 2008 American Institute of Physics.},
	keywords = {ELECTRIC-DIPOLE INTERACTIONS, electrostatic, FIELD GRADIENT, interactions, KRISTALLINFLUSSIGEN PHASE, MEAN TORQUE, MOLECULAR-STRUCTURE, MOLEKULAR-STATISTISCHE THEORIE, MONTE-CARLO SIMULATIONS, NMR, SOLVENTS},
	isbn = {0021-9606},
	url = {<Go to ISI>://000255456300083},
	author = {Burnell, E. E. and ter Beek, L. C. and Sun, Z. M.}
}
@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 {4107,
	title = {Monte Carlo simulations of solute ordering in nematic liquid crystals: Shape anisotropy and quadrupole-quadrupole interactions as orienting mechanisms},
	journal = {Physical Review E},
	volume = {55},
	number = {4},
	year = {1997},
	note = {ISI Document Delivery No.: WV249Times Cited: 17Cited Reference Count: 51},
	month = {Apr},
	pages = {4321-4337},
	type = {Article},
	abstract = {Monte Carlo computer simulations were used to investigate the effects of shape anisotropy and electrostatic interactions as mechanisms for orientational ordering of solutes in nematic liquid crystals. The simulation results were analyzed in terms of two theories of solute ordering which derive mean-field orientational potentials from the intermolecular pair potential. In the calculations, solute and solvent molecular shapes were approximated by hard ellipsoids. Most simulations also incorporated the interaction between point quadrupole moments placed at the centers of the ellipsoids. In the hard-core systems, orientational order parameters and distribution functions were calculated for a collection of different solutes under a variety of conditions. A theory due to Terzis and Photinos [Mol. Phys. 83, 847 (1994)] was found to underestimate the effect of shape anisotropy on orientational ordering drastically. The introduction of an effective solvent packing fraction was unable to improve the predictive power of the theory significantly. The quadrupolar systems were used to investigate a mean-field model for solute ordering which considers an interaction between the solute molecular quadrupole moment with an average electric-field gradient. The simulations indicate that the electric-field gradient sampled by the solute is highly dependent on the properties of the solute, contrary to some experimental evidence. Further, the effects of the intermolecular quadrupolar interactions on orientational ordering and the electric-field gradient were analyzed using a mean-field potential derived here and based on the theory due to Emsley, Palke, and Shilstone [Liq. Cryst. 9, 649 (1991)]. This model was found to provide a qualitatively correct but quantitatively imprecise prediction of orientational ordering.},
	keywords = {acetylene, COMPUTER-SIMULATION, ELECTRIC-DIPOLE INTERACTIONS, HARD ELLIPSOIDS, MEAN TORQUE, MOLECULAR-HYDROGEN, NMR, orientational order, POTENTIALS, SOLVENTS},
	isbn = {1063-651X},
	url = {<Go to ISI>://A1997WV24900067},
	author = {Polson, J. M. and Burnell, E. E.}
}
@article {3801,
	title = {Monte Carlo simulations of orientational ordering of solutes in a nematic solvent: Comparison with mean-field models},
	journal = {Molecular Physics},
	volume = {88},
	number = {3},
	year = {1996},
	note = {ISI Document Delivery No.: UT951Times Cited: 16Cited Reference Count: 23},
	month = {Jun},
	pages = {767-782},
	type = {Article},
	abstract = {Monte Carlo simulations were used to study orientational ordering of solutes in a nematic phase. Nematogens were modelled as hard prolate ellipsoids with an axis ratio of 5:1. Solutes were also modelled as hard prolate ellipsoids, with a variety of sizes and shape anisotropies. Solute order parameters and singlet orientational distribution functions were analysed using several mean-field models. The results confirm that these empirical mean-field potentials are closely linked to the anisotropic short-range repulsive forces that are crucial for the formation of the nematic phase.},
	keywords = {ANISOTROPIC SYSTEMS, COMPUTER-SIMULATION, ELECTRIC-DIPOLE INTERACTIONS, LIQUID-CRYSTALS, MOLECULES, NEMATOGEN, PHASE, POTENTIALS, SIZE},
	isbn = {0026-8976},
	url = {<Go to ISI>://A1996UT95100015},
	author = {Polson, J. M. and Burnell, E. E.}
}
