@article {1068,
	title = {NMR as a tool in the investigation of fundamental problems in ordered liquids},
	journal = {Solid State Nuclear Magnetic Resonance},
	volume = {28},
	number = {2-4},
	year = {2005},
	note = {ISI Document Delivery No.: 998NHTimes Cited: 9Cited Reference Count: 49},
	month = {Sep},
	pages = {73-90},
	type = {Article},
	abstract = {An overview is presented of modern NMR techniques and a variety of experimental and theoretical tools employed in the study of solutes dissolved in liquid crystals. The NMR techniques involve multiple quantum and spectral subtraction methods, In addition, various experimental and theoretical tools are discussed, including: the theoretical background of observed order parameters; the use of,magic mixtures{\textquoteright} to separate orientational contributions; the reorientation-vibration interaction; the use of model calculations based on size and shape of the various solutes; and the use of computer simulations. Applications to the benchmark probe molecules hydrogen, methane, ethane, and butane and their isotopomers are treated. (c) 2005 Elsevier Inc. All rights reserved.},
	keywords = {ANISOTROPIC LIQUIDS, butane, ethane, H-2 NMR, HYDROGEN, INTERNAL-ROTATION, liquid crystal, METHANE, MOLECULES, MOLEKULAR-STATISTISCHE THEORIE, MULTIPLE-QUANTUM NMR, NEMATISCHEN KRISTALLINFLUSSIGEN PHASE, NMR, NUCLEAR-MAGNETIC-RESONANCE, order parameter, orientational order, PROTON DIPOLAR COUPLINGS, SMALL CHAIN},
	isbn = {0926-2040},
	url = {<Go to ISI>://000234325100003},
	author = {Burnell, E. E. and de Lange, C. A.}
}
@article {1121,
	title = {Theoretical studies of alkyl radicals in the NaY and HY zeolites},
	journal = {J. Phys. Chem. A},
	volume = {109},
	number = {32},
	year = {2005},
	note = {ISI Document Delivery No.: 954TRTimes Cited: 8Cited Reference Count: 68},
	month = {Aug},
	pages = {7242-7250},
	type = {Article},
	abstract = {<p>Interplay of quantum mechanical calculations and experimental data on hyperfine coupling constants of ethyl radical in zeolites at several temperatures was engaged to study the geometries and binding energies and to predict the temperature dependence of hyperfine splitting of a series of alkyl radicals in zeolites for the first time. The main focus is on the hyperfine interaction of alkyl radicals in the NaY and HY zeolites. The hyperfine splitting for neutral free radicals and free radical cations is predicted for different zeolite environments. This information can be used to establish the nature of the muoniated alkyl radicals in the NaY and HY zeolites via mu SR experiments. The ration hyperfine coupling constants of the ethane radical cation in these zeolites are very large with relatively little dependence on temperature. It was found that the intramolecular dynamics of alkyl free radicals are only weakly affected by their strong binding to zeolites. In contrast, the substrate binding has a significant effect on their intermolecular dynamics.</p>},
	keywords = {CYCLOHEXADIENYL RADICALS, DENSITY-FUNCTIONAL CALCULATIONS, ELECTRON-SPIN-RESONANCE, ethyl, GAS-PHASE, HYPERFINE COUPLING-CONSTANTS, INTERNAL-ROTATION, INTRAMOLECULAR MOTION, METHYL, REORIENTATIONAL DYNAMICS},
	isbn = {1089-5639},
	url = {<Go to ISI>://000231178300029},
	author = {K. Ghandi* and Zahariev, F. E. and Wang, Y. A.}
}
@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 {4371,
	title = {The forbidden rotational Q-branch of CH3CF3: Torsional properties and (A(1)-A(2)) splittings},
	journal = {Journal of Molecular Spectroscopy},
	volume = {190},
	number = {2},
	year = {1998},
	note = {ISI Document Delivery No.: 103JBTimes Cited: 8Cited Reference Count: 29},
	month = {Aug},
	pages = {324-340},
	type = {Article},
	abstract = {The pure rotational spectrum driven by the small distortion dipole moment perpendicular to the symmetry axis has been investigated between 8 and 18 GHz for CH3CF3 in the ground vibrational state using a pulsed Fourier transform waveguide spectrometer. This molecule has been selected as a prototype for the case of a symmetric top with small (similar to 500 kHz) torsional energy splittings in the ground torsional state (v(6) = 0). In this state, six (k +/- 3 <{\textendash} k) e-branch series have been measured for lower state K = \k\ between 3 and 8 with 27 less than or equal to J less than or equal to 75, For (v(6) = 1), three series with lower state K between 5 and 7 with 49 less than or equal to J less than or equal to 66 have been observed. In two of these series, the torsional fine structure extending over similar to 6.8 MHz has been fully resolved. The (A(1) - A(2)) splitting has been measured in the (v(6) = 0) series (K = 6 <{\textendash} 3) for 37 less than or equal to J less than or equal to 74. The global data set of 443 frequencies included avoided-crossing molecular-beam splittings of Meerts and Ozier (1991. Chem. Phys. 152, 241-259) and mm-wave R-branch measurements of Bocquet et nl. (1994. J, Mol. Spectrosc. 165, 494-499). In a weighted least-squares analysis, a good fit was obtained by varying 18 parameters in a Hamiltonian that represented both the torsional effects and the sextic splittings. Effective values have been determined for both rotational constants, eight torsional parameters including the barrier height, six diagonal centrifugal distortion constants, and two centrifugal distortion constants (epsilon and epsilon(J)) that characterize the (Delta k = +/-3) matrix elements. The difficulties are discussed that arise in defining a unique model for the torsional terms in the Hamiltonian when a high barrier symmetric top is investigated by distortion moment spectroscopy. The redundancies are investigated that exist in the quartic and sextic Hamiltonian for a near-spherical top such as CH3CF3. (C) 1998 Academic Press.},
	keywords = {CH3SIH3, CROSSING MOLECULAR-BEAM, INTERNAL-ROTATION, METHYL SILANE, MICROWAVE FOURIER-TRANSFORM, MILLIMETER-WAVE, POLYATOMIC-MOLECULES, SPECTROSCOPY, SPECTRUM, SYMMETRIC, TOPS},
	isbn = {0022-2852},
	url = {<Go to ISI>://000075153100016},
	author = {Ozier, I. and Schroderus, J. and Wang, S. X. and McRae, G. A. and Gerry, M. C. L. and Vogelsanger, B. and Bauder, A.}
}
@article {3930,
	title = {A temperature dependence study of small solutes in zero electric field gradient nematic liquid crystal mixtures},
	journal = {Molecular Physics},
	volume = {90},
	number = {3},
	year = {1997},
	note = {ISI Document Delivery No.: WK754Times Cited: 10Cited Reference Count: 50},
	month = {Feb},
	pages = {303-313},
	type = {Article},
	abstract = {The temperature dependences of the proton nuclear magnetic resonance (NMR) spectra of the solutes 1,3,5-trichlorobenzene, metadichlorobenzene, orthodichlorobenzene, 1,3-bromochlorobenzene, benzene and 2-butyne have been studied in the special {\textquoteright}zero electric field gradient{\textquoteright} mixtures 55wt\% 1132-N-(4-ethoxybenzylidene)-4{\textquoteright}-n-butylaniline (EBBA) and 70wt\% (4-n-pentyl)-4{\textquoteright}-cyanobiphenyl-EBBA. The order parameter matrices obtained for each solute from an analysis of the NMR spectra indicate that the solutes experience a similar anisotropic potential in both mixtures.},
	keywords = {BIAXIAL SOLUTE, CONFORMATIONAL EQUILIBRIUM, INTERNAL-ROTATION, MOLECULES, NORMAL-BUTANE, orientational order, POTENTIAL FUNCTION, RAMAN-SPECTRA, SHAPE, SOLVENTS},
	isbn = {0026-8976},
	url = {<Go to ISI>://A1997WK75400001},
	author = {Chandrakumar, T. and Burnell, E. E.}
}
@article {3630,
	title = {A multiple-quantum H-1 NMR study of conformational biasing of biphenyl in a nematic liquid crystal},
	journal = {Journal of Magnetic Resonance Series A},
	volume = {118},
	number = {2},
	year = {1996},
	note = {ISI Document Delivery No.: TZ082Times Cited: 24Cited Reference Count: 42},
	month = {Feb},
	pages = {264-271},
	type = {Article},
	abstract = {Multiple-quantum H-1 NMR spectroscopy was used to simplify the analysis of the complicated one-quantum spectrum of the 10-spin molecule biphenyl dissolved in a nematic solvent. An eight-quantum spectrum was analyzed to obtain estimates of all dipolar coupling constants and chemical shifts, which were used as a starting point to solve the one-quantum spectrum, The dipolar couplings from the one-quantum spectrum were used, in combination with those determined in a previous study using different liquid-crystal solvents, to obtain vibrationally corrected geometrical parameters and orientational order parameters, The effective internal rotational potential was found to be shifted slightly toward a more planar configuration relative to the gas-phase potential, with an equilibrium dihedral angle of 37 degrees. (C) 1996 Academic Press, Inc.},
	keywords = {BARRIER, DERIVATIVES, GASEOUS, INTERNAL-ROTATION, MIXTURES, MOLECULAR-STRUCTURE, PERDEUTERATED BIPHENYL, SOLVENTS, SPECTRA, SPECTROSCOPY, STATE},
	isbn = {1064-1858},
	url = {<Go to ISI>://A1996TZ08200013},
	author = {Chandrakumar, T. and Polson, J. M. and Burnell, E. E.}
}
@article {3664,
	title = {Spin relaxation of muonium-substituted ethyl radicals (MuCH(2)CH(2)) in the gas phase},
	journal = {Journal of Chemical Physics},
	volume = {105},
	number = {17},
	year = {1996},
	note = {ISI Document Delivery No.: VP288Times Cited: 20Cited Reference Count: 84},
	month = {Nov},
	pages = {7517-7535},
	type = {Article},
	abstract = {The spin relaxation of the muonium-substituted ethyl radical (MuCH(2)CH(2)) and its deuterated analog (MuCD(2)CD(2)) has been studied in the gas phase in both transverse and longitudinal magnetic fields spanning the range similar to 0.5-35 kG, over a pressure range from similar to 1-16 atm at ambient temperature. The Mu(13)CH(2)(13)CH(2) radical has also been investigated, at 2.7 atm. For comparison, some data is also reported for the MuCH(2)C(CH3)(2) (Mu-t-butyl) radical at a pressure of 2.6 atm. This experiment establishes the importance of the mu SR technique in studying spin relaxation phenomena of polyatomic radicals in the gas phase, where equivalent ESR data is sparse or nonexistent. Both T-1 (longitudinal) and T-2 (transverse) mu SR relaxation rates are reported and interpreted with a phenomenological model. Relaxation results from fluctuating terms in the spin Hamiltonian, inducing transitions between the eigenstates assumed from an isotropic hyperfine interaction. Low-field relaxation is primarily due to the electron, via both the nuclear hyperfine (S . A . I) and the spin rotation interactions (S . J), communicated to the muon via the isotropic muon-electron hyperfine interaction. At the highest fields, direct spin flips of the muon become important, due to fluctuations in the anisotropic part of the muon-electron hyperfine interaction. In the intermediate held region a muon-electron {\textquoteright}{\textquoteright}flip-flop{\textquoteright}{\textquoteright} relaxation mechanism dominates, due partly to the anisotropic hyperfine interaction and partly to modulation of the isotropic muon-electron hyperfine coupling. In the case of the T-2 rates, electron relaxation mechanisms dominate over a much wider field range than for the T-1 rates, and inhomogeneous line broadening also contributes. The fluctuations that induce both the T-1 and T-2 relaxation rates are described by a single correlation time, tau(c), inversely proportional to the pressure. An effective spin-reorientation cross section is deduced from this pressure dependence, sigma(J) similar to 100+/-20 Angstrom(2), for all topically substituted ethyl radicals. This is similar to the geometrical cross section, but about a factor of 4 larger than values of sigma(J) found for similar-sized diamagnetic molecules by gas phase NMR, primarily reflecting the longer range of the electron-induced intermolecular potential. (C) 1996 American Institute of Physics.},
	keywords = {ADDITION-REACTIONS, DYNAMICS, EXCHANGE, HYPERFINE COUPLING-CONSTANTS, INTERNAL-ROTATION, LATTICE RELAXATION, LEVEL-CROSSING, MAGNETIC-RESONANCE, MUONATED RADICALS, ORGANIC FREE-RADICALS, SPECTROSCOPY},
	isbn = {0021-9606},
	url = {<Go to ISI>://A1996VP28800027},
	author = {Fleming, Donald G. and Pan, J. J. and Senba, M. and Arseneau, D. J. and Kiefl, R. F. and Shelley, M. Y. and Cox, S. F. J. and Percival, P. W. and Brodovitch, J. C.}
}
@article {3487,
	title = {CONFORMATIONAL EQUILIBRIUM AND ORIENTATIONAL ORDERING - H-1-NUCLEAR MAGNETIC-RESONANCE OF BUTANE IN A NEMATIC LIQUID-CRYSTAL},
	journal = {Journal of Chemical Physics},
	volume = {103},
	number = {16},
	year = {1995},
	note = {ISI Document Delivery No.: TA441Times Cited: 25Cited Reference Count: 60},
	month = {Oct},
	pages = {6891-6902},
	type = {Article},
	abstract = {In this study we use multiple-quantum H-1-NMR spectroscopy to study butane, the simplest flexible alkane, dissolved in a nematic solvent. An analysis of the highly accurate H-1 dipolar coupling constants gives important information about conformational and orientational behavior, including the hans-gauche energy difference, E(tg), and the conformer probabilities and order parameters. An essential component of the analysis involves the use of mean-field models to describe the orientational ordering of solutes in a nematic solvent. Several models were found to adequately describe the molecular ordering, including the chord model of Photinos et al. [D. J. Photinos, E. T. Samulski, and H. Toriumi, J. Phys. Chem. 94, 4688 (1990)] and recent versions of a model proposed by Burnell and co-workers [D. S. Zimmerman and E. E. Burnell, Mel. Phys. 78, 687 (1993)]. It was found that E(tg) lies in the range 2.1-3.0 kJ/mol, which is significantly below most experimental estimates of the gas-phase value. An attempt to describe more realistically the conformational states by including torsional fluctuations about the rotational isomeric states did not significantly improve the quality of the fits or alter the results. Finally the anisotropic component of the solute-solvent interaction was found to perturb only marginally the conformational probabilities from the isotropic values. (C) 1995 American Institute of Physics.},
	keywords = {ALKYL CHAINS, ANISOTROPIC LIQUIDS, ELECTRON-DIFFRACTION, INTERNAL-ROTATION, MOLECULAR-DYNAMICS, N-BUTANE, NORMAL-HEXANE, POTENTIAL FUNCTION, PROTON DIPOLAR COUPLINGS, STATISTICAL-MECHANICS},
	isbn = {0021-9606},
	url = {<Go to ISI>://A1995TA44100007},
	author = {Polson, J. M. and Burnell, E. E.}
}
@article {3053,
	title = {MICROWAVE-SPECTRUM OF TETROLYL FLUORIDE},
	journal = {Journal of the Chemical Society-Faraday Transactions},
	volume = {90},
	number = {20},
	year = {1994},
	note = {ISI Document Delivery No.: PN019Times Cited: 5Cited Reference Count: 17},
	month = {Oct},
	pages = {3023-3027},
	type = {Article},
	abstract = {{The microwave spectrum of the unstable molecule tetrolyl fluoride (but-2-ynoyl fluoride)},
	keywords = {BARRIER, DIMETHYLACETYLENE, INTERNAL-ROTATION},
	isbn = {0956-5000},
	url = {<Go to ISI>://A1994PN01900001},
	author = {Hensel, K. D. and Gerry, M. C. L.}
}
