References of "Lagerwall, Jan 50002154"
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See detailCoaxial Electrospinning of Liquid Crystal-containing Poly(vinyl Pyrrolidone) Microfibers
Enz, Eva; Baumeister, Ute; Lagerwall, Jan UL

in Beilstein Journal of Organic Chemistry (2009), 5(58), 103762558

With the relatively new technique of coaxial electrospinning, composite fibres of poly(vinylpyrrolidone) with the liquid crystal 4-cyano-4′-octylbiphenyl in its smectic phase as core material could be ... [more ▼]

With the relatively new technique of coaxial electrospinning, composite fibres of poly(vinylpyrrolidone) with the liquid crystal 4-cyano-4′-octylbiphenyl in its smectic phase as core material could be produced. The encapsulation leads to remarkable confine- ment effects on the liquid crystal, inducing changes in its phase sequence. We conducted a series of experiments to determine the effect of varying the relative flow rates of inner and outer fluid as well as of the applied voltage during electrospinning on these composite fibres. From X-ray diffraction patterns of oriented fibres we could also establish the orientation of the liquid crystal molecules to be parallel to the fibre axis, a result unexpected when considering the viscosity anisotropy of the liquid crystal kept in its smectic phase during electrospinning. [less ▲]

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See detailOn the balance between syn- and anticlinicity in smectic phases formed by achiral hockey-stick mesogens with and without chiral dopants
Enz, Eva; Findeisen-Tandel, Sonja; Dabrowski, Roman et al

in Journal of Materials Chemistry (2009), 19(19), 2950-2957

A series of achiral hockey-stick-shaped mesogens forming tilted smectic liquid crystal phases of synclinic SmC- as well as anticlinic SmCa-type was prepared and characterized. While all homologues exhibit ... [more ▼]

A series of achiral hockey-stick-shaped mesogens forming tilted smectic liquid crystal phases of synclinic SmC- as well as anticlinic SmCa-type was prepared and characterized. While all homologues exhibit both phases, the balance shifts from anticlinic to synclinic order upon elongation of the terminal chain at the meta-position, defining the hockey-stick shape. The elongation also leads to an increased kinetic hindrance of the transition between syn- and anticlinic phases and a decreased transition enthalpy. These observations indicate that a well-defined kink (short meta-substituted chain) promotes the anticlinic structure while a higher flexibility between kinked and rod-shape (long meta-substituted chain) promotes synclinic order. An intermediate chain-length homologue was selected as host material for doping with syn- and anticlinic rod-shaped chiral dopants, respectively, at varying concentrations. Opposite of what might be expected the balance between syn- and anticlinic order was not simply dictated by the choice of dopant. Instead, both types of tilting order prevailed with roughly the same strength as in the achiral host regardless of which chiral material was added, up to concentrations well beyond normal doping conditions. Thus, at least with hockey-stick-shaped achiral hosts, syn- as well as anticlinic chiral compounds can be used effectively as chiral dopants without necessarily having an important impact on the clinicity of the resulting mixture. The hockey-stick design concept should be useful in producing achiral anticlinic-forming mesogens for low-polarization, long-pitch antiferroelectric liquid crystal mixtures. Finally, we point out that a mixture study like the one carried out here yields a conclusive means of establishing the clinicity of achiral tilted smectics, an endeavour that can sometimes be far from trivial. [less ▲]

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See detailElectrolyte effects on the stability of nematic and lamellar lyotropic liquid crystal phases – colligative and ion-specific aspects
Dawin, Ute; Lagerwall, Jan UL; Giesselmann, Frank

in Journal of Physical Chemistry B (2009), 113(33), 11414-11420

We investigated the electrolyte effects on the stability of nematic and lamellar lyotropic liquid crystalline (LLC) phases formed by the simple anionic surfactant cesium pentadecafluorooctanoate (CsPFO ... [more ▼]

We investigated the electrolyte effects on the stability of nematic and lamellar lyotropic liquid crystalline (LLC) phases formed by the simple anionic surfactant cesium pentadecafluorooctanoate (CsPFO) in water. To the lyotropic guest phase, at the constant CsPFO-mass fraction of 0.55, the series of electrolytes LiCl, NaCl, KCl, CsCl, CsI, and Cs2SO4, respectively, was added at concentrations ranging from 0.5 to 2.5 mol %. With increasing electrolyte concentration two substantially different effects were observed. At low concentrations all added electrolytes caused an increase of the thermal stability of the LLC phases, favoring the lamellar phase over the nematic phase. This behavior is, at least qualitatively, understood within the packing parameter model. The extent of the stabilization clearly depends on the chemical nature of the added cation. For a given cation, however, the effect is colligative, i.e., independent of the chemical nature of the added anion. At higher salt concentrations a salting-out-like phase separation was induced. This effect is clearly ion-specific as the salting-out concentration varied for each cation following the order of the Hofmeister series for cations. [less ▲]

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See detailMacroscopic-scale carbon nanotube alignment via self-assembly in lyotropic liquid crystals
Schymura, Stefan; Enz, Eva; Roth, Siegmar et al

in Synthetic Metals (2009), 159(21-22), 2177-2179

By dispersing carbon nanotubes (CNTs) in a lyotropic liquid crystalline matrix, uniaxial alignment of the nanotubes can easily be achieved over macroscopic areas. We briefly describe the principles behind ... [more ▼]

By dispersing carbon nanotubes (CNTs) in a lyotropic liquid crystalline matrix, uniaxial alignment of the nanotubes can easily be achieved over macroscopic areas. We briefly describe the principles behind the technique and then show that it can be applied to multiwall as well as single-wall nanotubes and that a variety of different dispersing materials can be used, from industrial surfactants to DNA. We also present a new microfluidics-based method for transferring the liquid crystal-dispersed CNTs to a substrate, maintaining a fair control of tube direction. (C) 2009 Elsevier B.V. All rights reserved. [less ▲]

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See detailCarbon nanotubes in liquid crystals
Lagerwall, Jan UL; Scalia, Giusy

in Journal of Materials Chemistry (2008), 18(25), 2890-2898

We review the research on carbon nanotube (CNT) dispersion in liquid crystals (LCs), focusing mainly on the approaches where the aim is to align CNTs along the LC director field, but also covering briefly ... [more ▼]

We review the research on carbon nanotube (CNT) dispersion in liquid crystals (LCs), focusing mainly on the approaches where the aim is to align CNTs along the LC director field, but also covering briefly the proposed possibility to enhance thermotropic LCs by CNT doping. All relevant LC types are considered: thermotropic LC hosts allowing dynamic CNT realignment, lyotropic LC hosts allowing very high concentration of CNTs uniformly aligned over macroscopic areas and consequent removal of the LC, and LC phases formed by CNTs themselves, used in spinning high-quality carbon nanotube fibres. We also discuss the issue of CNT dispersion in some detail, since successful nanotube separation is imperative for success in this field regardless of the type of LC that is considered. We end by defining a few major challenges for the development of the field over the next few years, critical for reaching the stage where industrially viable protocols for LC-based CNT alignment can be defined. [less ▲]

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See detailSpontaneous macroscopic carbon nanotube alignment via colloidal suspension in hexagonal columnar lyotropic liquid crystals
Scalia, Giusy; von Bühler, Clemens; Hägele, Constanze et al

in Soft Matter (2008), 4(3), 570-576

The self-assembly of amphiphilic molecules in aqueous solution into lyotropic liquid crystals (LCs), characterised by soft yet long-range ordered nanoscale structures, constitutes a fascinating phenomenon ... [more ▼]

The self-assembly of amphiphilic molecules in aqueous solution into lyotropic liquid crystals (LCs), characterised by soft yet long-range ordered nanoscale structures, constitutes a fascinating phenomenon at the heart of soft matter science which can be employed in a manifold of creative ways. Particularly interesting structures may arise as a result of functionalisation of the LC with appropriate guest molecules, adopting the order of their host. Here we combine cat- and anionic surfactants to form a liquid-crystalline colloidal suspension of carbon nanotubes (CNTs), which by virtue of the spontaneously formed hexagonal columnar LC structure are uniaxially aligned over macroscopic areas. The nanotube concentration can be so high, with sufficiently uniform alignment, that the mixture becomes a fluid linear polariser, the anisotropic optical properties of CNTs having been transferred to macroscopic scale by the LC. Moreover, thin and highly aligned filaments can be drawn and deposited in selected directions on arbitrary surfaces, after which the LC template can be rinsed away. Combined with recently developed methods for CNT fractionation according to chirality, the technique would yield an unprecedented degree of control in the practical realisation of carbon nanotube-based devices and materials. [less ▲]

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See detailCoaxial Electrospinning of Microfibres With Liquid Crystal in the Core
Lagerwall, Jan UL; McCann, J. T.; Formo, Eric et al

in Chemical Communications (2008), 42

Liquid crystal containing composite fibres were produced via coaxial electrospinning, demonstrating that this technique can be used for producing new functional fibres and/or to study the impact of ... [more ▼]

Liquid crystal containing composite fibres were produced via coaxial electrospinning, demonstrating that this technique can be used for producing new functional fibres and/or to study the impact of extreme confinement on liquid crystal phases. [less ▲]

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See detailAntiferroelectric liquid crystals with induced intermediate polar phases and the effects of doping with carbon nanotubes
Lagerwall, Jan UL; Dabrowski, R.; Scalia, G.

in Journal of Non-Crystalline Solids (2007), 353(47-51), 4411-4417

By mixing a commercial broad-temperature-range nematic liquid crystal mixture with a single-component antiferroelectric chiral smectic exhibiting two different chiral smectic-C-type phases as only ... [more ▼]

By mixing a commercial broad-temperature-range nematic liquid crystal mixture with a single-component antiferroelectric chiral smectic exhibiting two different chiral smectic-C-type phases as only mesophases, we have induced three phases which appear in neither of the two components; the paraelectric SmA* phase and the so-called intermediate phases SmC􏰀b and SmC􏰀c, antiferroelectric and heli- electric in nature, respectively. The generation of the two latter phases in mixtures where one component is an essentially non-chiral nematic is highly unexpected, since these phases are generally linked to high degree of smectic order and/or strong chiral interactions. It is probably made possible through microphase segregation driven by the incompatibility of the fluorinated tail of the smectic compo- nent with the non-fluorinated constituents of the nematic mixture. We also doped the nematic with single-wall carbon nanotubes (SWCNTs) before adding it to the smectic at the same concentration, allowing us to study the effect of SWCNTs on antiferroelectric liquid crystals. Although the final SWCNT concentration was very small (0.002 wt%) the phase sequence was radically altered, the ordin- ary SmC* phase now being present all the way between SmA* and crystallization, while all other variations of smectic-C-type order were suppressed. [less ▲]

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See detailCarbon nanotubes in liquid crystals as versatile functional materials
Scalia, Giusy; Lagerwall, Jan UL; Schymura, Stefan et al

in Physica Status Solidi B. Basic Research (2007), 244(11), 4212-4217

Liquid crystals can be easily aligned in desired directions by treated surfaces or by external fields. The least ordered liquid crystal phase, the nematic, exhibits orientational order that can be easily ... [more ▼]

Liquid crystals can be easily aligned in desired directions by treated surfaces or by external fields. The least ordered liquid crystal phase, the nematic, exhibits orientational order that can be easily transferred onto carbon nanotubes dispersed in it. The alignment of the carbon nanotubes can be demonstrated by po- larized Raman spectroscopy. Carbon nanotubes not only well integrate in the matrix but also, even at very low concentration, have a detectable effect on the liquid crystal properties that can be very attractive for display applications. The presence of big aggregates of carbon nanotubes, on the other hand, interfere strongly with the switching behaviour of the liquid crystal, as we can show following the local switching of liquid crystal molecules with Raman spectroscopy. [less ▲]

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See detailPartitioning and reorientational dynamics of phenylalcohols in SDS lyotropic liquid crystalline mesophases: An alc-μsr study
Martyniak, Aleksandra; Dilger, Herbert; Mckenzie, Iain et al

in Colloids and Surfaces A : Physicochemical and Engineering Aspects (2007), 309

Avoided level crossing muon spin resonance (ALC-􏰝SR) has been applied to monitor location and reorientational dynamics of two different sets of muoniated cyclohexadienyl radicals derived from 3 ... [more ▼]

Avoided level crossing muon spin resonance (ALC-􏰝SR) has been applied to monitor location and reorientational dynamics of two different sets of muoniated cyclohexadienyl radicals derived from 3-phenylpropan-1-ol and 5-phenylpentan-1-ol as tracer molecules in SDS–water–pentanol ternary mixtures and in SDS–water–pentanol–dodecane quaternary systems. The present results show a dependence of the phenylalcohol partitioning on the environment polarity and on the structure of the SDS dispersions. Both radicals tend to be incorporated within the mesophases at 25◦C. The low polarity sensed by the tracer molecule indicates that among all mesophases these species are immersed the deepest in the sponge phase. Alternatively, the effect could be explained by a dependence of the water gradient in the surfactant layer on the overall water versus hydrocarbon content of a system. The changing amplitudes, widths and shapes of the 􏰰1 resonances reveal a different extent of dynamics of three isomers of the muoniated 3-phenylpropan-1-ol radical in particular mesophases. The most extensive dynamics occurs in the hexagonal phase. The probe molecule chain length and the fractions of pentanol and dodecane are additional factors that affect partitioning. [less ▲]

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See detailMolecular model for de Vries type smectic-A–smectic-C phase transition in liquid crystals
Gorkunov, M. V.; Giesselmann, Frank; Lagerwall, Jan UL et al

in Physical Review. E : Statistical, Nonlinear, and Soft Matter Physics (2007), 75(6), 060701

We develop both phenomenological and molecular-statistical theory of smectic-A-smectic-C phase transition with anomalously weak smectic layer contraction. Using a general mean-field molecular model, we ... [more ▼]

We develop both phenomenological and molecular-statistical theory of smectic-A-smectic-C phase transition with anomalously weak smectic layer contraction. Using a general mean-field molecular model, we demonstrate that a relatively simple interaction potential suffices to describe the transition both in conventional and de Vries type smectics. The theoretical results are in excellent agreement with experimental data. The approach can be used to describe tilting transitions in other soft matter systems. [less ▲]

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See detailNanotube alignment using lyotropic liquid crystals
Lagerwall, Jan UL; Scalia, G.; Haluska, Miroslav et al

in Advanced Materials (2007), 19(3), 359-364

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See detailOrder-disorder molecular model of the smectic-A-smectic-C phase transition in materials with conventional and anomalously weak layer contraction
Gorkunov, M. V.; Osipov, M. A.; Lagerwall, Jan UL et al

in Physical Review. E : Statistical, Nonlinear, and Soft Matter Physics (2007), 76(5), 051706

We develop a molecular-statistical theory of the smectic-A-smectic-C transition which is described as a transition of the order-disorder type. The theory is based on a general expansion of the effective ... [more ▼]

We develop a molecular-statistical theory of the smectic-A-smectic-C transition which is described as a transition of the order-disorder type. The theory is based on a general expansion of the effective interaction potential and employs a complete set of orientational order parameters. All the order parameters of the smectic-C phase including the tilt angle are calculated numerically as functions of temperature for a number of systems which correspond to different transition scenario. The effective interaction potential and the parameters of the transition are also calculated for specific molecular models based on electrostatic and induction interaction between molecular dipoles. The theory successfully reproduces the main properties of both conventional and so-called ``de Vries-type'' smectic liquid crystals, clarifies the origin of the anomalously weak layer contraction and describes the tricritical behavior at the smectic-A-smectic-C transition. The ``de Vries behavior,'' i.e., anomalously weak layer contraction is also obtained for a particular molecular model based on interaction between longitudinal molecular dipoles. A simple phenomenological model is presented enabling one to obtain explicit expressions for the layer spacing and the tilt angle which are used to fit the experimental data for a number of materials. [less ▲]

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See detailSimultaneous alignment and dispersion of carbon nanotubes with lyotropic liquid crystals
Lagerwall, Jan UL; Scalia, G.; Haluska, Miroslav et al

in Physica Status Solidi B. Basic Research (2006), 243(13), 3046-3049

We demonstrate that single-wall carbon nanotubes (SWCNTs) can be macroscopically aligned by means of templating in a lyotropic nematic liquid crystal (LC), a self-assembling anisotropic fluid with orienta ... [more ▼]

We demonstrate that single-wall carbon nanotubes (SWCNTs) can be macroscopically aligned by means of templating in a lyotropic nematic liquid crystal (LC), a self-assembling anisotropic fluid with orienta- tional but no translational order. The CNTs spontaneously adopt the alignment of the host, as we verify by means of resonant Raman spectroscopy. The aqueous LC host, based on the surfactant SDS, simultane- ously keeps the nanotubes well dispersed over time scales of months or longer. The LC can be loaded with CNTs to almost the same extent as the standard isotropic 1% surfactant solutions normally used for dispersing CNTs without any optically visible bundling occurring. [less ▲]

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See detailThe peculiar optic, dielectric and x-ray diffraction properties of a fluorinated de vries asymmetric-diffuse-cone-model ferroelectric liquid crystal
Lagerwall, Jan UL; Coleman, D.; Körblova, E. et al

in Liquid Crystals (2006), 33(1), 17-24

A new semi-fluorinated chiral smectic liquid crystal, W504, is investigated by electro-optic, dielectric and X-ray scattering experiments. It exhibits a huge dielectric soft mode response, strong ... [more ▼]

A new semi-fluorinated chiral smectic liquid crystal, W504, is investigated by electro-optic, dielectric and X-ray scattering experiments. It exhibits a huge dielectric soft mode response, strong electroclinic effect and a birefringence which increases considerably with the director tilt angle theta; typical characteristics of a SmA - SmC transition following the de Vries asymmetric diffuse cone (ADC) model in which the non-zero director tilt in SmC arises through an ordering of tilting directions rather than an actual increase in average molecule tilt <theta(mol)>. In W504 a small increase in <theta(mol)> of about 4 degrees is however detected in the SmC phase. Although the increase in molecule inclination is much less than the increase in director tilt h, saturating close to 30 degrees, it leads to a shrinkage of the smectic layers by about 1 angstrom, a result of the large initial molecule tilt in the SmA phase, <theta(mol)>(SmA) approximate to 30 degrees. The tilting transition in W504 is thus mainly an ADC model disorder - order transition, but it also has a component of a structural transition. The semi- fluorinated molecular structure of W504 leads to a very weak electron density modulation along the layer normal, giving a vanishing form factor in bulk samples which exhibit no (001) X-ray scattering peak. In thin films the (001) peak is however observed, indicating that the electron density modulation is enhanced by the breaking of the head - tail symmetry of the liquid crystal phase at the LC - air interface. [less ▲]

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See detailOn the change in helix handedness at transitions between the sm-c* and sm-ca* phases in chiral smectic liquid crystals
Lagerwall, Jan UL; Giesselmann, Frank; Osipov, Mikhail A.

in Liquid Crystals (2006), 33(6), 625-633

Using a discrete model for the synclinic SmC* and the anticlinic SmC􏰀a phases we give a theoretical explanation for the fact that the helix twisting sense reverses at a transition between these phases ... [more ▼]

Using a discrete model for the synclinic SmC* and the anticlinic SmC􏰀a phases we give a theoretical explanation for the fact that the helix twisting sense reverses at a transition between these phases (direct transition or via the so-called chiral smectic C ‘subphases’) and we derive an explicit expression for the helical pitch in the SmC􏰀a phase. As the theory shows and as we also demonstrate experimentally, the reversal is of a different nature from helix inversions within a single phase, where the inversion is always coupled to a pitch divergence. At a clinicity change the common behaviour is instead pitch-shortening on approaching the phase transition and the associated helix twisting sense reversal. The phenomenon may be put to use in smart mixing in order to control the helix pitch, either for achieving long pitch for surface-stabilized ferroelectric and antiferroelectric liquid crystal displays; or a very short pitch, in the case of devices utilizing the deformed helix mode. [less ▲]

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See detailCurrent topics in smectic liquid crystal research
Lagerwall, Jan UL; Giesselmann, Frank

in Chemphyschem : A European Journal of Chemical Physics and Physical Chemistry (2006), 7(1), 20-45

Interest in the smectic liquid-crystalline state of matter received a substantial boost with the discovery by Meyer in the mid-1970s that a chiral smectic C (SmC*) phase exhibits a spontaneous elec- tric ... [more ▼]

Interest in the smectic liquid-crystalline state of matter received a substantial boost with the discovery by Meyer in the mid-1970s that a chiral smectic C (SmC*) phase exhibits a spontaneous elec- tric polarization, and with the subsequent demonstration by Clark and Lagerwall of the surface-stabilized SmC* ferroelectric liquid crystal at the beginning of the 1980s. Since then, chiral smectic phases and their plethora of polar effects have dominat- ed the research in this field, which today has reached a mature state where the first commercial microdisplay applications are now shipping in millions-per-year quantities. In this Review we discuss some of the topics of highest interest in current smectic liquid crystal research, and address application-relevant research (de Vries-type tilting transitions without defect generation and high-tilt antiferroelectric liquid crystals with perfect dark state) as well as more curiosity-driven research (the nature and origin of the chiral smectic C subphases and their intermediate frustrated states between ferro- and antiferroelectricity). [less ▲]

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See detailBook review: Crystals that flow
Lagerwall, Jan UL

in Technikgeschichte (2006), 73

Ein bekanntes Zitat von Mark Twain lautet "ein Klassiker ist ein Werk, das jeder gelesen ha- ben möchte, aber niemand lesen will". Mit dem ausgezeichneten Buch Crystals that flow - classic papers from the ... [more ▼]

Ein bekanntes Zitat von Mark Twain lautet "ein Klassiker ist ein Werk, das jeder gelesen ha- ben möchte, aber niemand lesen will". Mit dem ausgezeichneten Buch Crystals that flow - classic papers from the history of liquid crystals haben die drei Autoren Timothy J. Sluckin, David A. Dunmur und Horst Stegemeyer, vielen technik- und wissenschaftsinteressierten Le- sern das Klassikerlesen wesentlich erleichtert, da sie in diesem Buch 46 klassische Artikel aus der Geschichte der Erforschung und technischen Anwendung von Flüssigkristalle zu- sammengestellt haben. Sie erzählen damit die Geschichte, wie eine ‚akademische Kuriosität’, entdeckt Ende des neunzehnten Jahrhunderts, erst unsere Vorstellung von den Aggregatzu- ständen kondensierter Materie verändert hat, und danach zu einer Schlüsseltechnologie ent- wickelt wurde, die die Grundlagen der heutigen Multimillionen-Euro-Industrie der Flachbild- schirme liefert (LCD = Liquid Crystal Display, also Flüssigkristallanzeige). ... [less ▲]

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See detailEffect of phenyl rings in liquid crystal molecules on swcnts studied by raman spectroscopy
Scalia, G.; Lagerwall, Jan UL; Haluska, Miroslav et al

in Physica Status Solidi B. Basic Research (2006), 243(13), 3238-3241

Carbon nanotubes can be aligned by dispersing them in a liquid crystalline matrix. To control and opti- mize the obtained alignment it is important to understand the interactions between the molecules of ... [more ▼]

Carbon nanotubes can be aligned by dispersing them in a liquid crystalline matrix. To control and opti- mize the obtained alignment it is important to understand the interactions between the molecules of the liquid crystal host phase and the carbon nanotubes. To this end we have carried out resonant Raman spec- troscopy investigations of dispersions of single-wall carbon nanotubes (SWCNTs) in a liquid crystal com- pound comprising molecules with a biphenyl rigid core structure. We detect a distinct wavenumber shift of the radial breathing modes, confirming that the carbon nanotubes interact with the surrounding liquid crystal molecules, most likely through aromatic interactions (π-stacking). The interactions between liquid crystal host and nanotube guests are also evident from a polarizing microscopy study of the liquid crys- tal – isotropic phase transition in the proximity of bundles of nanotubes. The ordered liquid crystal phase is stable up to higher temperatures around the bundles than in areas without visible signs of CNTs. Con- versely, the transition from the disordered isotropic phase to the liquid crystal phase on cooling always nucleates at the carbon nanotube bundles. [less ▲]

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See detailFrustration between syn- and anticlinicity in mixtures of chiral and non-chiral tilted smectic-c-type liquid crystals
Lagerwall, Jan UL; Heppke, Gerd; Giesselmann, Frank

in European Physical Journal E. Soft Matter (2005), 18(1), 113-121

We study the effects of mixing ferroelectric and antiferroelectric liquid-crystal compounds (FLCs and AFLCs) when the former are strictly synclinic and the latter strictly anticlinic, i.e. one mixture ... [more ▼]

We study the effects of mixing ferroelectric and antiferroelectric liquid-crystal compounds (FLCs and AFLCs) when the former are strictly synclinic and the latter strictly anticlinic, i.e. one mixture component exhibits only SmC* and the other only SmCa* as tilted phase. Three different paths between syn- and anticlinicity were detected: transition directly between SmC* and SmCa*, transition via the SmCβ* and SmCγ* subphases, or by “escaping” the clinicity frustration by reducing the tilt to zero, i.e. the SmA* phase is extended downwards in temperature, separating SmC* from SmCa* in the phase diagram. The most common path is the one via the subphases, demonstrating that these phases appear as a result of frustration between syn- and anticlinic and, consequently, between syn- and antipolar order. For assessing the role of chirality, we also replaced the FLC with non-chiral synclinics. With one of the AFLCs, the route via supbhases was detected even in this case, suggesting that chirality —although necessary— does not have quite the importance that has previously been attributed to the appearance of the subphases. The path chosen in the mixture study seemed to be determined mainly by the synclinic component, the subphase induction occurring only when the SmA*-SmC* transition was second order. [less ▲]

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