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	Nematic - Wikipedia, the free encyclopedia
		The transition from the isotropic liquid state to the nematic phase is a (often weak) first-order phase transition.
		Nematics have fluidity similar to that of ordinary (isotropic) liquids but they can be easily aligned by an external magnetic or electric field.
		An aligned nematic has the optical properties of a uniaxial crystal and this makes them extremely useful in liquid crystal displays (LCD).
	en.wikipedia.org /wiki/Nematics (277 words)

	Encyclopedia :: encyclopedia : Liquid crystal (Site not responding. Last check: 2007-11-01)
		One of the most common LC phases is the nematic, where the molecules have no positional order, but they do have long-range orientational order.
		Most nematics are uniaxial: they have one axis that is longer and preferred, with the other two being equivalent (can be approximated as cylinders).
		Some liquid crystals are biaxial nematics, meaning that in addition to orienting their long axis, they also orient along a secondary axis.
	www.hallencyclopedia.com /Liquid_crystal (2944 words)

	NLO Liquid Crystals
		Chiral nematics are obtained by adding small quantities of chiral molecules to the material.
		The nonlinear optical response of a nematic is enhanced over two orders of magnitude, when small amount (~ 0.1%) of suitable dye is added to the material.
		The effect is quite general: it is observed both in the nematic phase and in the isotropic phase of the liquid crystal, and it should be present in any anisotropic absorbing liquid [D. Paparo et al.
	people.na.infn.it /~santamat/Lcuk.html (501 words)

	e-Prints Soton - Representation of pair correlations in nematics
		A complete expansion of equilibrium pair correlation functions for a uniaxial nematic phase composed of axially symmetric, non-polar and chiral molecules is proposed.
		Full advantage is taken of the symmetry of the nematic state and of the molecules.
		The explicit analysis and classification of the terms involving spherical harmonics with indices not exceeding 4 is given and illustrated using computer simulations for the nematic phase of a Gay-Berne mesogen.
	eprints.soton.ac.uk /19559 (183 words)

	Nematics
		Nematics have orientational order only, and, hence, among liquid crystals, they have the highest symmetry.
		The properties of nematics are fully described by the molecular director field n(r,t) or, equivalently, by their tensor order parameter Q
		The degeneration in the plane orthogonal to n reflects the uniaxial character of nematics.
	people.na.infn.it /~santamat/lc_tutorial/doc/nematics.htm (94 words)

	Rayleigh-Benard Instability in Nematics (Site not responding. Last check: 2007-11-01)
		We have shown that in a layer of a nematic liquid crystals, the mechanism of the Rayleigh-Bénard instabilities is drastically modified by the anisotropy of the thermal conductivity.
		In the presence of this distorsion the heat flux is deflected from the vertical direction due to the anisotropy of the thermal conductivity.
		From the same scheme it is also obvious that the convection of the heat by flows tends to cool the rising portions of the nematic and, as expected, leads to the "isotropic" feedback loop which has a stabilising action.
	www.lps.u-psud.fr /Collectif/gr_15/R_B_Inst_LC.htm (852 words)

	Anisotropic diffusion of light in large monodomain nematics
		Nematic phases scatter light due to local variations of the director.
		Large nematics are therefore opaque and diffuse light waves.
		We have performed time-resolved light diffusion experiments on liquid crystals in a monodomain nematic phase, which allowed us to observe the anisotropy in the diffusion constant for the first time.
	flux.aps.org /meetings/YR99/CENT99/abs/S8385010.html (198 words)

	OhioLINK ETD: Stojadinovic, Strahinja
		Dynamical properties of the nematic and isotropic phase of several relatively new bent-core liquid crystals, as contrasted to conventional straight-core ("calamitic") liquid crystals, have been systematically studied by dynamic light scattering.
		Observations: Nematic phases are rather uncommon in bent-core compounds because nematic structure occurs only if the molecules can rotate relatively freely around their long axis, the condition apparently met in only a fraction of bent-core materials synthesized so far.
		The obtained results show that the elasticity to viscosity ratio for uniaxial bent-core nematics is typically two orders of magnitude lower than for straight-core nematics, due evidently to the large viscosity associated with optic axis distortions in the bent-core case.
	www.ohiolink.edu /etd/view.cgi?kent1105330884 (398 words)

	Brazilian Journal of Physics - Thermotropic biaxial nematics: [1] highly desirable materials, still elusive? (Site not responding. Last check: 2007-11-01)
		Nevertheless, an indisputable example of a thermotropic biaxial nematic phase is surely expected to be found in the nearer future.
		Furthermore, another feasibility of the creation or promotion of the biaxial character of the nematic phase, focused on here, is conceivable and may lie in the flanks of the molecules due to intermolecularly side-to-side interacting forces of attraction and repulsion.
		Inadvertently, in a recent paper on biaxial nematic [11, page 256] one phenyl ring of their trimeric gigantocyclic oligomer was omitted.
	www.scielo.br /scielo.php?pid=S0103-97332002000300017&script=sci_arttext&tlng=en (3404 words)

	Topological defects in nematic liquid crystals
		Nematics being the liquid crystals made of thin long molecules which tend to line up their axes.
		the order parameter space of 2D nematic is circumference of the circle like in the case of planar spins but with the opposite points identified.
		The homotopy group of for the defects in nematics is the integers modulo 2
	www.rcp.ijs.si /dean/tdefect_revtex/node4.html (328 words)

	Liquid Crystals: a Simple View on a Complex Matter
		In nematics, the long molecular axes are preferably oriented in one direction, defined as the director n, (Fig.9), and molecular dipoles are compensated, so in equilibrium this mesophase is electrically neutral.
		Nematic LCs possess a relatively low viscosity; they can be deformed by even small external forces.
		Considering only weak distortions, the nematic phase formally acts as an elastic medium, and the deformations can be treated by the continuum theory of nematics.
	dept.kent.edu /spie/liquidcrystals/nematics1.html (244 words)

	About Liquid Crystals (Site not responding. Last check: 2007-11-01)
		Nematics are polarizable rod-like organic molecules on the order of 20 Angstroms in length.
		Because of their tendency to organize themselves in a parallel fashion, they demonstrate interesting and useful optical properties; the digital watch you used to wear back in the 80's functioned using nematic liquid crystals.
		Smectic Liquid crystals are different from nematics in that they have one more degree of orientational order than do the nematics.
	dwb.unl.edu /Teacher/NSF/C01/C01Links/www.lci.kent.edu/lc.html (311 words)

	Liquid Crystal Technology Homepage
		This helical internal structure is key to the operation of Twisted Nematic (TN) liquid crystal displays.
		In such displays a nematic is placed between two crossed polarizers and the molecules at the cell surfaces are aligned such that the director lies parallel to the polarizers (see Fig.
		Without the liquid crystal present light entering from the top of the cell would not be transmitted through the cell due to the crossed polarizers.
	www.eng.ox.ac.uk /lc/introduction/nematics_1.html (398 words)

	Liquid Crystals: a Simple View on a Complex Matter (Site not responding. Last check: 2007-11-01)
		Chiral molecules cause a twist in the nematic structure.
		They consist of quasi-nematic layers, whose individual directors are turned by a fixed angle on proceeding from one layer to the next (Fig.11).
		Although the nematics and cholesterics are similar in their basic structures, the optical properties of the cholesterics is significantly different due to the strong twisting.
	dept.kent.edu /spie/liquidcrystals/cholesterics1.html (207 words)

	Novel Glass-Forming Liquid Crystals. 6. High-Temperature Glassy Nematics
		To furnish new insight into structure-property relationships governing glassy nematic liquid crystals, novel material systems were synthesized and characterized.
		It was found that a linear nematogen, such as the cyanoterphenyl group, contributes to an elevated glass transition temperature and a wide nematic fluid temperature range with a mixed or an extended core structure.
		A stereochemical modification of the bicyclooctene ring from an exo-, exo- to an endo-, and exo-configuration, fluorination of the cyanophenylnaphthyl group, and a longer spacer to nematic pendants were found to depress T
	pubs.acs.org /cgi-bin/abstract.cgi/cmatex/2001/13/i12/abs/cm010266k.html (232 words)

	MicrotipsUSA \|\| Company
		A: Twisted Nematics (TN) was one of the earlier fluid technology that was implemented in LCDs TN type displays are primarily used in digital calculators, digital wristwatches, digital clocks and in some Caller ID boxes.
		Twisted Nematic uses a 90-degree twist to the molecules between one alignment layer and the other.
		Super Twisted Nematic displays improve on the more common TN screens by increasing the rotation of the molecules in their off state to over 260 degrees.
	www.microtipsusa.com /content/Products_FAQS.asp (2109 words)

	[No title]
		Phase conjugation in dye-activated nematics in the field of pulsed ruby laser radiation
		Phase conjugation of radiation from a free-running ruby laser by a thermal nonlinearity of dye-activated nematics was demonstrated.
		The temperature dependence of R was investigated theoretically and experimentally.
	www.turpion.org /php/paper.phtml?journal_id=qe&paper_id=473 (107 words)

	Rheo-NMR Publications
		Michail Lukaschek, Gerd Kothe, Claudia Schmidt, Alexandre E. Gomes, and Antonino Polimeno, Evaluation of the viscoelastic properties of a nematic dimer by cone-and-plate rheo-nuclear magnetic resonance spectroscopy and comparison with Leslie–Ericksen theory, J.
		Goncales LN, Casqhilho JP, Figueirinhas J, et al, NMR-study of the long-time, defect-controlled, magnetic reorientation of a nematic polymer liquid-crystal, Liq.
		ESNAULT, J.P. MARTINS and A. BLUMSTEIN, Reorientation Instabilities and Viscoelastic Measurements in a Main-Chain Thermotropic Nematic Polymer: Optical and NMR Studies., Liquid Crystals, 7, 607-628, (1990).
	www.rheo-nmr.com /researchpublications.php (1777 words)

	Correlation between Molecular Structure and Helicity of Induced Chiral Nematics in Terms of Short-Range and ...
		The helical structure of the chiral nematic phases induced by chiral dopants in nematic solvents provides a macroscopic image of the molecular chirality of the dopant promoted by the orientational order.
		Chiral biphenyls are challenging systems because their twisting ability shows a strong dependence on the molecular structure, which does not conform to empirical correlation rules.
		These are described, respectively, by a shape model and a reaction field method, having the common characteristics of a realistic representation of the structure and properties of the chiral dopants in terms of molecular surface, atom charges, and distributed polarizabilities.
	pubs.acs.org /cgi-bin/abstract.cgi/jacsat/2001/123/i32/abs/ja010406r.html (269 words)

	e-Prints Soton - NMR determination of the physical properties of nematics (Site not responding. Last check: 2007-11-01)
		Certain physical properties of nematics can be obtained from the field-induced static and dynamic director orientations in thin films.
		This powerful approach is illustrated with specifically deuteriated 4-pentyl-4'-cyanobiphenyl (5CB) subject to the magnetic field of the spectrometer and an electric field applied at an angle to it.
		When the electric field is applied to the nematic, the director moves from being parallel to the magnetic field to being at an angle to it (the turn-on process) because and are both positive for 5CB.
	eprints.soton.ac.uk /37674 (658 words)

	Physical properties of liquid crystals: Nematics - The IET (Site not responding. Last check: 2007-11-01)
		7.1 - Refractive indices of nematic mesophases D.A. Dunmur
		8.2 - Measurements of viscosities in nematics J.
		The Institution is a not for profit organisation, registered as a charity in the UK.
	www.iee.org /Publish/Books/EMIS/em025c.cfm (534 words)

	Physical Properties of Liquid Crystals: Nematics (Site not responding. Last check: 2007-11-01)
		This book provides a data source and insight into the properties of nematic liquid crystals governing the performance of liquid crystal display devices (LCDs).
		Display devices based on these crystals are a huge international industry and LCDs are part of the every-day life of many people.
		The physical properties of nematic liquid crystals determine the detailed operation of the various modes.
	www.booknews.co.uk /Books/1745.htm (110 words)

	ELECTROHYDRODYNAMIC INSTABILITY LIMITS OF NEMATICS (Site not responding. Last check: 2007-11-01)
		Zenginoglou HM, Kosmopoulos JA On the Cut-off Frequency In the Conduction Mode Electrohydrodynamic Instability of a Nematic Layer.
		Decay of spatially periodic patterns in a nematic liquid crystal
		Non-linear theory of flexoelectrically induced periodic distortions in nematic liquid crystals
	yako.physics.upatras.gr /zenginoglou/3-Research/Publications.html (1366 words)

	Lavrentovich Oleg D. -- Kent State University Liquid Crystal Institute
		S.V. Shiyanovskii, O.D. Lavrentovich, “3D Simulations of Nematic and Cholesteric Liquid Crystals in Complex Geometries,” SID Intnl.
		V.G. Nazarenko, O.D. Lavrentovich, “Anchoring Transition in a Nematic Liquid Crystal Composed of Centrosymmetric Molecules,” Phys.
		V.G. Bodnar, O.D. Lavrentovich and V.M. Pergamenshchik, "Threshold of structural hedgehog-ring transition in droplets of a nematic in an alternating electric field." Zh.Eksp.Teor.Fiz., v.101, 111-125 (1992)/ Sov.Phys.JETP, v.
	www.lci.kent.edu /PI/Lavrentovich.htm (3682 words)

	INI : Abstracts : PDSW02 : Microscopic models for collective motion: polar birdoids and active nematics. (Site not responding. Last check: 2007-11-01)
		The onset of collective motion in interacting particle systems is investigated via simple stochastic microscopic models, which can be regarded as a driven, out of equilibrium version of the simple Ising XY model.
		Interacting particles are characterized by an axial symmetry, either polar (polar birdoids) or apolar (active nematics) and are self propelled along their axis.
		Finally, comparison with experimental observations and theoretical predictions obtained from hydrodynamic-like mesoscopic equations is carried on.
	www.newton.cam.ac.uk /programmes/PDS/Poster2/ginelli.html (184 words)

	Physical Properties of Liquid Crystals: Nematics
		The demand for liquid crystals with better display parameters and lower power consumption has stimulated much research into their properties and characterization.
		A large team of over 50 leading researchers from the USA, Europe and Japan have focused their expertise to extract and review data on a wide range of properties of nematics, including those which are essential to the development of all types of liquid crystal device.
		Where appropriate these properties are also explained with expert commentary.
	www.knovel.com /knovel2/Toc.jsp?BookID=1135 (336 words)

	Citations: Oxford Workshop on Biaxial Nematics - see (ResearchIndex)
		113, 5971 5979 (2000) 1 Introducti5 Biaxial nematic phases have been a subject of great interest for some time and this interest is increasing as the chase for undisputed thermotropic biaxial nematics continues
		Part of this focused attention comes from the possibility of technological applications in the fast display area [2] but much of the fascination of the subject certainly originates from the basic research arena and from the hiatus between theoretical [3] and experimental predictions [4, 5]....
		....we 12 have found that a negative interaction biaxiality # # yields a stable and fairly wide biaxial nematic, that we have confirmed with a variety of observables.
	citeseer.ist.psu.edu /context/1900528/0 (250 words)

	The Society of Rheology: 69th Annual Meeting (Oct 1997) Abstract of Paper (Site not responding. Last check: 2007-11-01)
		Monodomains of liquid crystalline nematics were prepared between two parallel plates to study the effect of initial molecular orientation on shear.
		The director was initially aligned in the shear plane with a variation of alignment angle ranging from parallel with the shear direction, to parallel with the vorticity direction.
		The most recent experiments have focused on low molecular weight nematics such as 5-CB and MBBA.
	www.rheology.org /sor97a/abstract.asp?PaperID=169 (136 words)

	APS - 2006 APS March Meeting - Event - From Networks to Nematics -- Carbon Nanotubes as Soft Matter (Site not responding. Last check: 2007-11-01)
		APS - 2006 APS March Meeting - Event - From Networks to Nematics -- Carbon Nanotubes as Soft Matter
		Abstract: W4.00001 : From Networks to Nematics -- Carbon Nanotubes as Soft Matter
		Although we find remarkably low loading thresholds for elastic percolation, our results highlight a fundamental dilemma for the engineering of conducting carbon nanotube polymer composites; dispersion stability will often be achieved at the expense of electrical conductivity.
	meetings.aps.org /Meeting/MAR06/Event/45184 (277 words)

	UK-Italy Biaxiality Group (Site not responding. Last check: 2007-11-01)
		Please mark you talk with a footer indicating that the talk was given at the 2
		Molecular aspects and external field alignment of biaxial nematics
		New observations in the nematic and smectic phases formed from achiral bent-core molecules
	www.slci.soton.ac.uk /Biaxiality_meeting_Jan06.htm (139 words)

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