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 (linear and non linear). This excellent volume meets the need for an up-to-date text on liquid crystals.Nematic and Cholesteric Liq
This important and timely book deals with the theoretical and experimental investigation of the phase transitions which occur in complex fluid systems, namely lyotropic systems, microemulsions, colloids, gels, polymers, biological membranes, Langmuir monolayers, and ferrofluids. It contains 20-odd review papers from the major contributors to this rapidly growing field of research, summarizing the main results obtained in the description and understanding of the phase transitions taking place between the isotopic, nematic, cholesteric, lamellar, hexagonal, and cubic mesophases of complex fluids.
This book brings together the many concepts and discoveries in liquid crystal colloids contributed over the last twenty years and scattered across numerous articles and book chapters. It provides both a historical overview of the development of the field and a clear perspective on the future applications in photonics. The book covers all phenomena observed in liquid crystal colloids with an emphasis on experimental tools and applications of topology in condensed matter, as well as practical micro-photonics applications. It includes a number of spectacular manifestations of new topological phenomena not found or difficult to observe in other systems. Starting from the early works on nematic colloids, it explains the basics of topological defects in ordered media, charge and winding, and the elastic forces between colloidal particles in nematics. Following a detailed description of experimental methods, such as optical tweezing and particle tracking, the book eases the reader into the theoretical part, which deals with elastic deformation of nematic liquid crystals due to inclusions and surface alignment. This is discussed in the context of basic mean field Landau-de Gennes Q-tensor theory, with a brief explanation of the free-energy minimization numerical methods. There then follows an excursion into the topology of complex nematic colloidal structures, colloidal entanglement, knotting and linking. Nematic droplets, shells, handlebodies and chiral topological structures are addressed in separate chapters. The book concludes with an extensive chapter on the photonic properties of nematic dispersions, presenting the concept of integrated soft matter photonics and discussing the concepts of nematic and chiral nematic microlasers, surface-sensitive photonic devices and smectic microfibers. The text is complemented by a large bibliography, explanatory sketches and beautiful micrographs.
This book provides a didactic derivation of the main theories of thermotropic and lyotropic liquid crystals, revealing the common molecular-theoretic framework that underpins both theories. This unified context will help young researchers in coming to grips with the basics of the simplest of liquid crystals, being uniaxial nematic liquid crystals, easing them into the intricacies of more complex forms of such materials irrespective of whether they are thermotropic or lyotropic. The coverage provides a theoretical understanding of the phase behaviour, that is, what drives molecules and particles to spontaneously align themselves, as well as an appreciation of the role of entropy, energy and so on. The focus here is on the main theories for the isotropic-nematic transition, being the Maier-Saupe and the Onsager theories, and how they are derived from a common description, known as (classical) density functional theory (DFT). This book will be a valuable resource for senior undergraduate and graduate students, and experimentalists and engineers who feel intimidated by more formal or rigorous theoretical accounts and textbooks. Exercises at the end of each chapter help the reader to apply the basic concepts also to other types of liquid crystal, in particular the smectic liquid crystal.
This new edition of the classic text incorporates the many advances in knowledge about liquid crystals that have taken place since its initial publication in 1974. Entirely new chapters describe the types and properties of liquid crystals in terms of both recently discovered phases and current insight into the nature of local order and isotropic-to-nematic transition. There is an extensive discussion of the symmetrical, macroscopic, dynamic, and defective properties of smectics and columnar phases, with emphasis on order-of-magnitude considerations, all illustrated with numerous descriptions of experimental arrangements. The final chapter is devoted to phase transitions in smectics, including the celebrated analogy between smectic A and superconductors. This new version's topicality and breadth of coverage will ensure that it remains an indispensable guide for researchers and graduate students in mechanics and engineering, and in chemical, solid state, and statistical physics.
This text is a primer for liquid crystals, polymers, rubber and elasticity. It is directed at physicists, chemists, material scientists, engineers and applied mathematicians at the graduate student level and beyond.
Nuclear Magnetic Resonance Probes of Molecular Dynamics describes the theoretical basis and experimental techniques that make modern NMR spectroscopy a powerful and flexible tool for probing molecular dynamics in chemical, physical, and biochemical systems. Individual chapters, written by leaders in the development and application of NMR from around the world, treat systems that range from synthetic polymers, liquid crystals, and catalysts to proteins and oligonucleotides and techniques that include deuterium NMR, magic angle spinning, multidimensional spectroscopy, and magnetic resonance imaging. A combination of elementary and advanced material makes the book a useful introduction to the field for students at the graduate level as well as an important reference for practising NMR spectroscopists.
Since the development of the laser in the early 1960's, light scattering has played an increasingly crucial role in the investigation of many types of phase transitions and the published work in this field is now widely dispersed in a large number of books and journals.A comprehensive overview of contemporary theoretical and experimental research in this field is presented here. The reviews are written by authors who have actively contributed to the developments that have taken place in both Eastern and Western countries.
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.
This book describes the state of the art of our understanding of liquid-crystal interfaces on a molecular level. The interactions of liquid crystal molecules with a surface play an essential role in the operation of liquid crystal displays (LCD's) and other LC devices that are based on the controllable anchoring of LC molecules on polymer coated surfaces. This book addresses the microscopic interaction between a macromolecule (liquid crystal, polymer) and a wall, using state of the art surface and interface-sensitive experimental techniques, such as Atomic Force Microscopy (AFM), Scanning Tunneling Microscopy (STM), Linear and Nonlinear Optical Microscopy and (Dynamic) Light Scattering (DLS). These experimental techniques were complemented with computer simulations and supra molecular chemistry methods to develop controllable polymeric surfaces.