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 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 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 Symmetry and Structure of Freely Suspended Liquid Crystal Films written by Darren R. Link and published by . This book was released on 1998 with total page 330 pages. Available in PDF, EPUB and Kindle. Book excerpt:

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 Freely Suspended Liquid Crystalline Films written by A. A. Sonin and published by John Wiley & Sons. This book was released on 1998 with total page 192 pages. Available in PDF, EPUB and Kindle. Book excerpt: Freely Suspended Liquid Crystalline Films Andrei A. Sonin Centre d'Etudes Atomiques de Saclay, France and Institute of Crystallography, Russian Academy of Sciences with a Foreword by Professor Noel Clark University of Colorado, USA This book provides a brief introduction to the physics of liquid crystals and to macroscopic physical parameters characterising freely suspended liquid crystalline (FSLC) films, and then reviews the experimental techniques for preparing these films, measuring their thicknesses, and investigating their physical properties and structural aspects. Molecular structures and defects of FSLC films and the problems of film stability, thinning and rupture are discussed in later chapters. Physical phenomena, such as orientational and phase transitions, Frederick's and flexoelectric effects, hydroelectrodynamics, etc., are also analysed. Finally, some applications of FSLC films in industry and in various branches of science are discussed. Specialists working in the physics of liquid crystals and in surface physics will find this book of interest. Industrial firms and their research centres investigating liquid crystals, biological membranes, detergent/surfactant/biomedical areas; and graduates and postgraduates in solid state physics and crystallography will also benefit from this book. The book has an easy-to-read style with just the minimum amount of mathematics necessary to explain important concepts. This is the first book dedicated exclusively to the physics of FSLC in almost a century since their discovery and last twenty years of their active studies. Andrei Sonin, a scientist in the area of FSLC and author of many articles on surface phenomena in liquid crystals, the properties and behaviour of thin liquid crystalline and surfactant films, has a long standing reputation in liquid crystals and surfactant systems and has been particularly active in issues involving surface interactions.

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 Characterization of Liquid Crystal Structure Using Freely Suspended Films written by Nattaporn Chattham and published by . This book was released on 2004 with total page 180 pages. Available in PDF, EPUB and Kindle. Book excerpt:

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 Fluctuational Effects in the Dynamics of Liquid Crystals written by E.I. Kats and published by Springer Science & Business Media. This book was released on 1994 with total page 200 pages. Available in PDF, EPUB and Kindle. Book excerpt: Liquid crystals, widely used in displays for electronic equipment and other applications, have highly unusual properties arising from the anisotropy of their molecules. It appears that some aspects of the fluid dynamics of liquid crystals, such as their viscosity, can be understood only by considering the role played by thermal fluctuations. In order to provide a theoretical framework for understanding the experimental results, the authors devote a large part of the book to a derivation of the nonlinear dynamic equations and to a discussion of linearized equations for the various types of liquid crystals. The diagrammatic and other techniques they use are of general use in condensed matter physics, and this exposition should thus be of interest to all condensed-matter theorists.

Download or read book Structure and Dynamics of Complex Liquids written by Eleanor Meyer De Groot and published by . This book was released on 1995 with total page 384 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Structural Defects and Instabilities in Freely Suspended Liquid Crystal Films written by Jinzhong Pang and published by . This book was released on 1995 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Structure and Dynamics of Partially Solidified Systems written by D. Loper and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 475 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume contains papers presented at the NATO Advanced Research Workshop on the Structure and Dynamics of Partially Solidified Systems held at Stanford Sierra Lodge, Tahoe, California, May 12-16, 1986. This work shop grew out of a realization that there was a significant amount of interest and activity in this topic in several unrelated disciplines, and that it would be mutually beneficial to bring together those mathemati' cians, scientists and engineers interested in this subject to share their knowledge and ideas with each other. Partially solidified systems occur in a variety of natural and man made environments. Perhaps the most well-known occurrence involves the solidification of metallic alloys. Typically as a molten alloy is cooled, the solid phase advances from the cold boundary into the liquid as a branching forest of dendritic crystals. This creates a region of mixed solid and liquid phases, commonly referred to as a mushy zone, in which the solid forms a rigidly connected framework with the liquid occurring in the intercrystalline gaps. In addition to the casting of metallic alloys, mushy zones can occur in weld pools, the Earth's core and. mantle, magma chambers, temperate glaciers, frozen soils, frozen lakes and sea ice. A second mechanical configuration for the solid phase is as a suspension of small crystals within the liquid; this is referred to as a slurry.

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 Of Liquid Crystal Phases written by Peter S Pershan and published by World Scientific. This book was released on 1988-10-01 with total page 443 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 Liquid Crystals written by Irina Carlescu and published by BoD – Books on Demand. This book was released on 2019-01-03 with total page 106 pages. Available in PDF, EPUB and Kindle. Book excerpt: Liquid Crystals - Self-Organized Soft Functional Materials for Advanced Applications is focused on both theoretical models and experimental results, pointing out the chemical and physical properties (thermodynamics, electro-optic switching behavior, and non-linear optic phenomena) of liquid crystals used in a wide range of devices. In this respect, the chapters cover the following topics: chemical structure and phase transitions in bent-core liquid crystals, phase and structural behavior of liquid crystals used to align carbon nanotubes, molecular alignment, and photorefractive effect in the ferroelectric phase, which has the potential to be used as transistors, for image storage, and in optical signal processing. It is expected that the book will be of interest to researchers in academia and industries, as well as advanced students.