The Hydrodynamics Of Biaxial Nematic Liquid Crystals

In the nematic liquid crystal phase, rod-shaped molecules move randomly but remain essentially parallel to one another. Biaxial nematics, which were first predicted in 1970 by Marvin Freiser, have their molecules differentially oriented along two axes. They have the potential to create displays with fast switching times and may have applications in thin-film displays and other liquid crystal technologies. This book is the first to be concerned solely with biaxial nematic liquid crystals, both lyotropic and thermotropic, formed by low molar mass as well as polymeric systems. It opens with a general introduction to the biaxial nematic phase and covers: • Order parameters and distribution functions • Molecular field theory • Theories for hard biaxial particles • Computer simulation of biaxial nematics • Alignment of the phase • Display applications • Characterisation and identification • Lyotropic, thermotropic and colloidal systems together with material design With a consistent, coherent and pedagogical approach, this book brings together theory, simulations and experimental studies; it includes contributions from some of the leading figures in the field. It is relevant to students and researchers as well as to industry professionals working in soft matter, liquid crystals, liquid crystal devices and their applications throughout materials science, chemistry, physics, mathematics and display engineering.

This is a book on the dissipative dynamics of ordered fluids, with a particular focus on liquid crystals. It covers a whole range of different theories, mainly concerned with nematic liquid crystals in both their chiral and nonchiral variants. The authors begin by giving a detailed account of the molecular origins of orientational order in fluids. They then go on to develop a general framework in which continuum theories for ordered fluids can be phrased. Within this unified setting, they cover both well-established classical theories and new ones with aspects that are not yet completely settled. The book treats a wide range of hydrodynamic theories for liquid crystals, from the original 1960s works by Ericksen and Leslie to new, fast-developing ideas of liquid crystal science. The final chapter is devoted to nematoacoustics and its applications. Old experiments on the propagation of ultrasound waves in nematic liquid crystals are interpreted and explained in the light of a new theory developed within the general theoretical infrastructure proposed in the body of the book. This book is intended both for graduate students and professional scholars in mathematics, physics, and engineering of advanced materials. It delivers a solid framework for liquid crystal hydrodynamics and shows the unifying concepts at the basis of the classical theories. It illustrates how these concepts can also be applied to a wide variety of modern topics. Andre M. Sonnet is in the Department of Mathematics and Statistics at the University of Strathclyde, Glasgow (Scotland) and Epifanio G. Virga is in the Department of Mathematics at the University of Pavia (Italy). They have a long history of working together in liquid crystal science and have contributed, in particular, to the theories of defects and biaxial nematics.

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.

In the last 20 years the study of nonlinear nonequilibrium phenomena in spa tially extended systems, with particular emphasis on pattern-forming phenomena, has been one of the very active areas in physics, exhibiting interesting ramifi cations into other sciences. During this time the study of the "classic" systems, like Rayleigh-Benard convection and Taylor vortex flow in simple fluids, has also been supplemented by the study of more complex systems. Here liquid crystals have played, and are still playing, a major role. One might say that liquid crystals provide just the right amount and right kind of complexity. They are full of non linearities and give rise to new symmetry classes, which are sometimes actually simpler to deal with qualitatively, but they still allow a quantitative description of experiments in many cases. In fact one of the attractions of the field is the close contact between experimentalists and theorists. Hydrodynamic instabilities in liquid crystals had already experienced a period of intense study in the late 1960s and early 1970s, but at that time neither the ex perimental and theoretical tools nor the concepts had been developed sufficiently far to address the questions that have since been found to be of particular interest. The renewed interest is also evidenced by the fact that a new series of workshops has evolved. The first one took place in 1989 in Bayreuth and united participants from almost all groups working in pattern formation in liquid crystals.

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

Much more than a slight revision, this second edition of the successful "Handbook of Liquid Crystals" is completely restructured and streamlined, with updated as well as completely new topics, 100% more content and a new team of editors and authors. As such, it fills the gap for a definitive, single source reference for all those working in the field of organized fluids and will set the standard for the next decade. The Handbook's new structure facilitates navigation and combines the presentation of the content by topic and by liquid-crystal type: A fundamentals volume sets the stage for an understanding of the liquid crystal state of matter, while individual volumes cover the main types and forms, with a final volume bringing together the diverse liquid crystal phases through their applications. This unrivaled, all-embracing coverage represents the undiluted knowledge on liquid crystals, making the Handbook a must-have wherever liquid crystals are investigated, produced or used, and in institutions where their science and technology is taught. Also available electronically on Wiley Online Library, www.wileyonlinelibrary.com/ref/holc Volume 1: Fundamentals of Liquid Crystals Volume 2: Physical Properties and Phase Behavior of Liquid Crystals Volume 3: Nematic and Chiral Nematic Liquid Crystals Volume 4: Smectic and Columnar Liquid Crystals Volume 5: Non-Conventional Liquid Crystals Volume 6: Nanostructured and Amphiphilic Liquid Crystals Volume 7: Supermolecular and Polymeric Liquid Crystals Volume 8: Applications of Liquid Crystals

Essentially there are two variational theories of liquid crystals explained in this book. The theory put forward by Zocher, Oseen and Frank is classical, while that proposed by Ericksen is newer in its mathematical formulation although it has been postulated in the physical literature for the past two decades. The newer theory provides a better explanation of defects in liquid crystals, especially of those concentrated on lines and surfaces, which escape the scope of the classical theory. The book opens the way to the wealth of applications that will follow.