Download or read book Structure Formation and Dynamics in Molecularly Thin Smectic Liquid Crystal Films written by Benjamin Schulz and published by . This book was released on 2013 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This doctoral thesis presents a study of thin films of smectic liquid crystals. This class of material shows the property to form stable films of only a few molecules thickness both on substrates and freely suspended in air. This feature together with the anisotropy of the material offers the possibility to prepare and investigate samples that cannot be formed by other materials. As the dimensions of the films are reduced, the physical properties are expected to change with respect to the observed surface structures and the dynamics in the film. For freely suspended films, the presented wor ...

Download or read book Structure and Dynamics of Freely Suspended Liquid Crystals written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-06-21 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: Smectic liquid crystals are phases of rod shaped molecules organized into one dimensionally (1 D) periodic arrays of layers, each layer being between one and two molecular lengths thick. In the least ordered smectic phases, the smectics A and C, each layer is a two dimensional (2D) liquid. Additionally there are a variety of more ordered smectic phases having hexatic short range translational order or 2D crystalline or quasi long range translational order within the layers. The inherent fluid-layer structure and low vapor pressure of smectic liquid crystals enables the long term stabilization of freely suspended, single component, layered fluid films as thin as 30A, a single molecular layer. The layering forces the films to be an integral number of smectic layers thick, quantizing their thickness in layer units and forcing a film of a particular number of layers to be physically homogeneous with respect to its layer structure over its entire area. Optical reflectivity enables the precise determination of the number of layers. These ultrathin freely suspended liquid crystal films are structures of fundamental interest in condensed matter and fluid physics. They are the thinnest known stable fluid structures and have the largest surface-to-volume ratio of any stable fluid preparation, making them ideal for the study of the effects of reduced dimensionality on phase behavior and on fluctuation and interface phenomena. Their low vapor pressure and quantized thickness enable the effective use of microgravity to extend the study of basic capillary phenomena to ultrathin fluid films. Freely suspended films have been a wellspring of new LC physics. They have been used to provide unique experimental conditions for the study of condensed phase transitions in two dimensions. They are the only system in which the hexatic has been unambiguously identified as a phase of matter, and the only physical system in which fluctuations of a 2D XY system and Kosterlitz Thouless phase tran

Download or read book The Molecular Dynamics of Liquid Crystals written by G.R. Luckhurst and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 612 pages. Available in PDF, EPUB and Kindle. Book excerpt: Liquid-crystalline phases are now known to be formed by an ever growing range of quite diverse materials, these include those of low molecular weight as well as the novel liquid-crystalline polymers, such phases can also be induced by the addition of a solvent to amphiphilic systems leading to lyotropic liquid crystals. Irrespective of the structure of the constituent molecules these numerous liquid-cl)'Stailine phases are characterised by their long range orientational order. In addition certain phases exhibit elements of long range positional order. Our understanding, both experimental and theoretical, at the molecular level of the static behaviour of these fascinating and important materials is now well advanced. In contrast the influence of the long range order; both orientational and positional, on the molecular dynamics in liquid Cl)'Stais is less well understood. In an attempt to address this situation a NATO Advanced Study Institute devoted to liquid ctystal dynamics was held at n Ciocco, Barga, Italy in September 1989. This brought together experimentalists and theoreticians concerned with the various dynamical processes occurring in all liquid crystals. The skills of the participants was impressively wide ranging; they spanned the experimental techniques used in the study of molecular dynamics, the nature of the systems investigated and the theoretical models employed to understand the results. While much was learnt it was also recognised that much more needed to be done in order to advance our understanding of molecular dynamics in liquid Cl)'Stais.

Download or read book Structure Hydrodynamics and Phase Transition of Freely Suspended Liquid Crystals written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-06-15 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt: Smectic liquid crystals are phases of rod shaped molecules organized into one dimensionally (1D) periodic arrays of layers, each layer being between one and two molecular lengths thick. In the least ordered smectic phases, the smectics A and C, each layer is a two dimensional (2D) liquid. Additionally there are a variety of more ordered smectic phases having hexatic short range translational order or 2D crystalline quasi long range translational order within the layers. The inherent fluid-layer structure and low vapor pressure of smectic liquid crystals enable the long term stabilization of freely suspended, single component, layered fluid films as thin as 30A, a single molecular layer. The layering forces the films to be an integral number of smectic layers thick, quantizing their thickness in layer units and forcing a film of a particular number of layers to be physically homogeneous with respect to its layer structure over its entire area. Optical reflectivity enables the precise determination of the number of layers. These ultrathin freely suspended liquid crystal films are structures of fundamental interest in condensed matter and fluid physics. They are the thinnest known stable condensed phase fluid structures and have the largest surface-to-volume ratio of any stable fluid preparation, making them ideal for the study of the effects of reduced dimensionality on phase behavior and on fluctuation and interface phenomena. Their low vapor pressure and quantized thickness enable the effective use of microgravity to extend the study of basic capillary phenomena to ultrathin fluid films. Freely suspended films have been a wellspring of new liquid crystal physics. They have been used to provide unique experimental conditions for the study of condensed phase transitions in two dimensions. They are the only system in which the hexatic has been unambiguously identified as a phase of matter, and the only physical system in which fluctuations of a 2D XY system and Kosterl

Download or read book Bent Shaped Liquid Crystals written by Hideo Takezoe and published by CRC Press. This book was released on 2017-07-20 with total page 290 pages. Available in PDF, EPUB and Kindle. Book excerpt: Bent-Shaped Liquid Crystals: Structures and Physical Properties provides insight into the latest developments in the research on liquid crystals formed by bent-shaped mesogens. After a historical introduction, the expert authors discuss different kinds of mesophase structures formed by bent-shaped molecules. This book devotes the majority of its pages to physical properties such as polar switching, optics and non-linear optics, and behavior in restricted geometries. However, as chemistry is often highly relevant to the emergence of new phases, particularly with reflection symmetry breaking, it also involves a broad spectrum of interesting chemistry viewpoints.

Download or read book Smectic and Columnar Liquid Crystals written by Patrick Oswald and published by CRC Press. This book was released on 2005-12-09 with total page 724 pages. Available in PDF, EPUB and Kindle. Book excerpt: Liquid crystals allow us to perform experiments that provide insight into fundamental problems of modern physics, such as phase transitions, frustration, elasticity, hydrodynamics, defects, growth phenomena, and optics. Smectic and Columnar Liquid Crystals: Concepts and Physical Properties Illustrated by Experiments is a result of personal research and of the graduate lectures given by the authors at the École Normale Supérieure de Lyon and the University of Paris VII, respectively. The book examines lamellar (smectic) and columnar liquid crystals, which, in addition to orientational order, possess 1D, 2D or 3D positional order. This volume illustrates original physical concepts using methodically numerous experiments, theoretical developments, and diagrams. Topics include rheology and plasticity, ferroelectricity, analogies with superconductors, hexatic order and 2D-melting, equilibrium shapes, facetting, and the Mullins-Sekerka instability, as well as phase transitions in free films and membrane vibrations. Nematic and cholesteric liquid crystals are covered by the authors in a separate volume entitled Nematic and Cholesteric Liquid Crystals: Concepts and Physical Properties Illustrated by Experiments. Smectic and Columnar Liquid Crystals is an ideal introduction and a valuable source of reference for theoretical and experimental studies of advanced students and researchers in liquid crystals, condensed matter physics, and materials science.

Download or read book Structure of Liquid Crystal Phases written by P. S. Pershan and published by World Scientific. This book was released on 1988 with total page 450 pages. Available in PDF, EPUB and Kindle. Book excerpt: Current understanding of different phases as well as the phase transitions between them has only been achieved following recent theoretical advances on the effects of dimensionality in statistical physics. P S Pershan explains the connection between these two separate areas and gives some examples of problems where the understanding is still not complete. The most important example is the second order phase transition between the nematic and smectic-A phase. Others include the relation between the several hexatic phases that have been observed and the first order restacking transitions between phases that were all previously identified as smectic-B, but which should more properly be identified as crystalline-B. Some relatively recent experimental developments on the discotic phase, liquid crystal surfaces and lyotropic phases are also included. The book includes 41 major reprints of some of the recent seminal work on the structure of liquid crystals. They are introduced by a brief review of the symmetries and other properties of liquid crystalline phases. In addition, there is a discussion of the differences between true liquid crystalline phases and others that were described as liquid crystalline in the early literature, but which have since been shown to be true three-dimensional crystals. The progression from the isotropic fluid, through the nematic, smectic, and various crystalline phases can be understood in terms of a systematic decrease in symmetry, together with an accompanying variation in structure is explained. A guide to the selected reprints and a sort of ?Rosetta Stone? for these various phases is provided. The goal of this book is to explain the systematics of this progression to students and others that are new to this field, as well as to provide a useful handbook for people already working in the field.

Download or read book Optical Studies of Liquid Crystal Films written by Hui Hsiung and published by . This book was released on 1986 with total page 194 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Optical Investigations of Molecular Arrangement of Smectic Liquid Crystals written by Xifeng Han and published by . This book was released on 2004 with total page 190 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Smectic Liquid Crystals written by G. W. Gray and published by . This book was released on 1984 with total page 266 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Dynamics and Defects in Liquid Crystals written by Patricia Cladis and published by CRC Press. This book was released on 1998-08-27 with total page 490 pages. Available in PDF, EPUB and Kindle. Book excerpt: During his distinguished scientific career, Alfred Saupe made important contributions to liquid crystal research, laying the groundwork on which much of the current knowledge and research in the physics of liquid crystals is based. This volume features papers presented by Prof. Saupe's colleagues, students and friends at a festschrift in honor of his 70th birthday. In addition, a selection of Prof. Saupe's articles are reprinted in the original German and in English translation, offering the reader a unique opportunity to see both the early work of this important scientist and widespread effect of that work on later discoveries in liquid crystal physics.

Download or read book Structure and Properties of Liquid Crystals written by Lev M. Blinov and published by Springer Science & Business Media. This book was released on 2010-10-26 with total page 448 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book by Lev M. Blinov is ideal to guide researchers from their very first encounter with liquid crystals to the level where they can perform independent experiments on liquid crystals with a thorough understanding of their behaviour also in relation to the theoretical framework. Liquid crystals can be found everywhere around us. They are used in virtually every display device, whether it is for domestic appliances of for specialized technological instruments. Their finely tunable optical properties make them suitable also for thermo-sensing and laser technologies. There are many monographs written by prominent scholars on the subject of liquid crystals. The majority of them presents the subject in great depth, sometimes focusing on a particular research aspect, and in general they require a significant level of prior knowledge. In contrast, this books aims at an audience of advanced undergraduate and graduate students in physics, chemistry and materials science. The book consists of three parts: the first part, on structure, starts from the fundamental principles underlying the structure of liquid crystals, their rich phase behaviour and the methods used to study them; the second part, on physical properties, emphasizes the influence of anisotropy on all aspects of liquid crystals behaviour; the third, focuses on electro-optics, the most important properties from the applications standpoint. This part covers only the main effects and illustrates the underlying principles in greater detail. Professor Lev M. Blinov has had a long carrier as an experimentalist. He made major contributions in the field of ferroelectric mesophases. In 1985 he received the USSR state prize for investigations of electro-optical effects in liquid crystals for spatial light modulators. In 1999 he was awarded the Frederiks medal of the Soviet Liquid Crystal Society and in 2000 he was honoured with the G. Gray silver medal of the British Liquid Crystal Society. He has held many visiting academic positions in universities and laboratories across Europe and in Japan.

Download or read book One and Two Dimensional Fluids written by Antal Jakli and published by CRC Press. This book was released on 2006-05-30 with total page 351 pages. Available in PDF, EPUB and Kindle. Book excerpt: Smectic and lamellar liquid crystals are three-dimensional layered structures in which each layer behaves as a two-dimensional fluid. Because of their reduced dimensionality they have unique physical properties and challenging theoretical descriptions, and are the subject of much current research. One- and Two-Dimensional Fluids: Properties of Smec

Download or read book A Review of the Structure and Physical Properties of Liquid Crystals written by Glenn Halstead Brown and published by . This book was released on 1971 with total page 106 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Liquid Crystals Fundamentals written by Shri Singh and published by World Scientific. This book was released on 2002-11-05 with total page 549 pages. Available in PDF, EPUB and Kindle. Book excerpt: Liquid crystals are partially ordered systems without a rigid, long-range structure. The study of these materials covers a wide area: chemical structure, physical properties and technical applications. Due to their dual nature — anisotropic physical properties of solids and rheological behavior of liquids — and easy response to externally applied electric, magnetic, optical and surface fields liquid crystals are of greatest potential for scientific and technological applications. The subject has come of age and has achieved the status of being a very exciting interdisciplinary field of scientific and industrial research.This book is an outgrowth of the enormous advances made during the last three decades in both our understanding of liquid crystals and our ability to use them in applications. It presents a systematic, self-contained and up-to-date overview of the structure and properties of liquid crystals. It will be of great value to graduates and research workers in condensed matter physics, chemical physics, biology, materials science, chemical and electrical engineering, and technology from a materials science and physics viewpoint of liquid crystals.

Download or read book Structure Formation in Thin Liquid liquid Films written by Stefan Bommer and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We revisit the problem of a liquid polymer that dewets from another liquid polymer substrate with the focus on the direct comparison of results from mathematical modeling, rigorous analysis, numerical simulation and experimental investigations of rupture, dewetting dynamics and equilibrium patterns of a thin liquid-liquid system. The experimental system uses as a model system a thin polystyrene (PS) / polymethylmethacrylate (PMMA) bilayer of a few hundred nm. The polymer systems allow for in situ observation of the dewetting process by atomic force microscopy (AFM) and for a precise ex situ imaging of the liquid-liquid interface. In the present study, the molecular chain length of the used polymers is chosen such that the polymers can be considered as Newtonian liquids. However, by increasing the chain length, the rheological properties of the polymers can be also tuned to a viscoelastic flow behavior. The experimental results are compared with the predictions based on the thin film models. The system parameters like contact angle and surface tensions are determined from the experiments and used for a quantitative comparison. We obtain excellent agreement for transient drop shapes on their way towards equilibrium, as well as dewetting rim profiles and dewetting dynamics.

Download or read book Physics And Chemistry Of Molecular Assemblies written by Kazuchika Ohta and published by World Scientific. This book was released on 2020-03-17 with total page 206 pages. Available in PDF, EPUB and Kindle. Book excerpt: The JLCS Excellent Book Award 2021 by Japanese Liquid Crystal SocietyIn nature, a number of molecules self-assemble to form various aggregation states. In these aggregation states, numerous functions, which have never been observed in one molecule, are developed. Even for the same compound, the different aggregation states exhibit totally different physical properties in density, hardness, optical and electrical properties, medicinal effect, etc. For pursuing the functionality of materials, it may be indispensable to understand the molecular aggregation states of crystals, liquid crystals, glass, colloids, etc. In this book, the author will focus on the basis of polymorphic phenomena of crystals and liquid crystals and their physical properties. After reading this book, you will be able to change your viewpoint of matter from traditional limited 'three states of matter' to novel 'numerous states of matter.'