Download or read book Molecular Simulation of a Model Liquid Crystal written by Manoj K. Chalam and published by . This book was released on 1991 with total page 296 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 Liquid Crystal Sensors written by Albert Schenning and published by CRC Press. This book was released on 2017-09-01 with total page 164 pages. Available in PDF, EPUB and Kindle. Book excerpt: Liquid Crystal Sensors discusses novel applications of liquid crystals that lie beyond electrically driven optical switches and displays. The main focus is on recent progress in the area of sensors based on low molar mass and polymer liquid crystals. This area of research became "hot" in recent years since the possibilities for applications of liquid crystal sensors are growing in many areas, ranging from the detection of mechanical displacements to the detection of environmental pollutants and chemical agents. This book is well-suited for students, as well as scientists from different backgrounds. For students and researchers new to the field, it gives a thorough introduction. For experienced researchers it shows the latest breakthroughs and serves as an inspiration for solving problems or sparking new ideas. Key Features: Emphasizes how liquid crystals are extremely sensitive to external stimuli and therefore can be used for the construction of stimuli-responsive devices, such as sensors Includes the contributions of editors who are deeply involved in the field and author chapters on hot topics such as the sensitivity of liquid crystals to pollutants, UV light, and strain Provides an exclusive on LC sensors where having the data in one place will be very useful to the community Gives more information on sensors and broadens the scope by having a contributed volume rather than authored Combines recent data on advances in the area of liquid crystal sensors that includes many types of liquid crystal materials

Download or read book Molecular Simulation of Liquid Crystal Polymer Flow written by Radha Nayak and published by . This book was released on 1998 with total page 748 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Advances in the Computer Simulatons of Liquid Crystals written by Paolo Pasini and published by Springer Science & Business Media. This book was released on 2013-11-11 with total page 435 pages. Available in PDF, EPUB and Kindle. Book excerpt: Computer simulations provide an essential set of tools for understanding the macroscopic properties of liquid crystals and of their phase transitions in terms of molecular models. While simulations of liquid crystals are based on the same general Monte Carlo and molecular dynamics techniques as are used for other fluids, they present a number of specific problems and peculiarities connected to the intrinsic properties of these mesophases. The field of computer simulations of anisotropic fluids is interdisciplinary and is evolving very rapidly. The present volume covers a variety of techniques and model systems, from lattices to hard particle and Gay-Berne to atomistic, for thermotropics, lyotropics, and some biologically interesting liquid crystals. Contributions are written by an excellent panel of international lecturers and provides a timely account of the techniques and problems in the field.

Download or read book Molecular Aggregation written by Angelo Gavezzotti and published by OUP Oxford. This book was released on 2007 with total page 446 pages. Available in PDF, EPUB and Kindle. Book excerpt: This title provides a brief but accurate summary of all the basic ideas, theories, methods, and conspicuous results of structure analysis and molecular modelling of the condensed phases of organic compounds.

Download or read book Liquid Crystals and Their Computer Simulations written by Claudio Zannoni and published by Cambridge University Press. This book was released on 2022-07-31 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Standing as the first unified textbook on the subject, Liquid Crystals and Their Computer Simulations provides a comprehensive and up-to-date treatment of liquid crystals and of their Monte Carlo and molecular dynamics computer simulations. Liquid crystals have a complex physical nature, and, therefore, computer simulations are a key element of research in this field. This modern text develops a uniform formalism for addressing various spectroscopic techniques and other experimental methods for studying phase transitions of liquid crystals, and emphasises the links between their molecular organisation and observable static and dynamic properties. Aided by the inclusion of a set of Appendices containing detailed mathematical background and derivations, this book is accessible to a broad and multidisciplinary audience. Primarily intended for graduate students and academic researchers, it is also an invaluable reference for industrial researchers working on the development of liquid crystal display technology.

Download or read book Ionic Liquid Crystals written by Giacomo Saielli and published by MDPI. This book was released on 2019-06-24 with total page 108 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this book we have collected a series of state-of-the art papers written by specialists in the field of ionic liquid crystals (ILCs) to address key questions concerning the synthesis, properties, and applications of ILCs. New compounds exhibiting ionic liquid crystalline phases are presented, both of calamitic as well as discotic type. Their dynamic and structural properties have been investigated with a series of experimental techniques including differential scanning calorimetry, polarized optical spectroscopy, X-ray scattering, and nuclear magnetic resonance, impedance spectroscopy to mention but a few. Moreover, computer simulations using both fully atomistic and highly coarse-grained force fields have been presented, offering an invaluable microscopic view of the structure and dynamics of these fascinating materials.

Download or read book Computer Simulations of Liquid Crystals and Polymers written by Paolo Pasini and published by Springer Science & Business Media. This book was released on 2005-08-11 with total page 368 pages. Available in PDF, EPUB and Kindle. Book excerpt: Liquid crystals, polymers and polymer liquid crystals are soft condensed matter systems of major technological and scientific interest. An understanding of the macroscopic properties of these complex systems and of their many and interesting peculiarities at the molecular level can nowadays only be attained using computer simulations and statistical mechanical theories. Both in the Liquid Crystal and Polymer fields a considerable amount of simulation work has been done in the last few years with various classes of models at different special resolutions, ranging from atomistic to molecular and coarse-grained lattice models. Each of the two fields has developed its own set of tools and specialized procedures and the book aims to provide a state of the art review of the computer simulation studies of polymers and liquid crystals. This is of great importance in view of a potential cross-fertilization between these connected areas which is particularly apparent for a number of experimental systems like, e.g. polymer liquid crystals and anisotropic gels where the different fields necessarily merge. An effort has been made to assess the possibilities of a coherent description of the themes that have developed independently, and to compare and extend the theoretical and computational techniques put forward in the different areas.

Download or read book Computer Simulation of Cyclic Siloxane Based Liquid Crystals Molecular Dynamics and X Ray Scattering written by and published by . This book was released on 1992 with total page 59 pages. Available in PDF, EPUB and Kindle. Book excerpt: The molecular dynamics technique is employed in the present study to investigate molecular models of a liquid crystal (LC) based on cyclic penta(methylsiloxane) with combinations of cholesteryl4'-allyloxybenzoate and biphenyl-4'allyloxybenzoate mesogens, which is of technological importance because of attributes related to light processing media. The packing and structure exhibited by these commercially available cholesteric LC's show unusually well-defined interlayer order giving rise to high order X-ray reflections. The purpose of this investigation was to: (1) Investigate the conformational flexibility of the molecular arrangements and organization of this cyclic siloxane-based LC at room temperature, providing insight into the relative stability of the various models proposed. (2) Serve as an instructional reference describing the basic theory and use of molecular mechanics and dynamics for the study of large molecular systems. Results from the molecular dynamics calculations indicate the degree of conformational flexibility among the pendant mesogens of this molecular system, and its effects on interdigitation. In particular, the isolated disk model exhibits the most flexibility and greatest stability as indicated by mean dihedral angles and range for certain key torsions. The dynamics simulation of the cylinder pairs suggests a large conformational flexibility of the siloxane rings. Also, movements of the interdigitated mesogens were much higher for a fixed rings system than for the case where the ring atoms were free to move. X-ray scattering pattern calculations for the structures generated during the dynamics run demonstrate higher order than for the initial models.

Download or read book Biaxial Nematic Liquid Crystals written by Geoffrey R. Luckhurst and published by John Wiley & Sons. This book was released on 2015-02-23 with total page 408 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.

Download or read book Variational Principle for Nonequilibrium Steady States Tested by Molecular Dynamics Simulation of Model Liquid Crystal Systems written by Sten Sarman and published by . This book was released on 2019 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The purpose of the work presented in this chapter is to test a recently proven variational principle according to which the irreversible energy dissipation rate is minimal in the linear regime of a nonequilibrium steady state. This test is carried out by performing molecular dynamics simulations of liquid crystals subject to velocity gradients and temperature gradients. Since the energy dissipation rate varies with the orientation of the director of the liquid crystal relative to these gradients and is minimal at certain orientations, this is a stringent test of the variational principle. More particularly, a nematic liquid crystal model based on the Gay-Berne potential, which can be regarded as a Lennard-Jones fluid generalized to elliptical molecular cores, is studied under planar Couette flow, planar elongational flow, and under a temperature gradient. It is found that the director of a nematic liquid crystal consisting of rod-like molecules lies in the vorticity plane at an angle of about 20° to the stream lines in the planar Couette flow. In the elongational flow, it is parallel to the elongation direction, and it is perpendicular to the temperature gradient in a heat flow. These orientations are the ones where the irreversible energy dissipation rate is minimal, so that the variational principle is fulfilled in these three cases.

Download or read book Liquid Crystals and Their Interactions with Colloidal Particles and Phospholipid Membranes written by Evelina B. Kim and published by . This book was released on 2004 with total page 188 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Molecular Dynamics written by Perla Balbuena and published by Elsevier. This book was released on 1999-04-22 with total page 971 pages. Available in PDF, EPUB and Kindle. Book excerpt: The latest developments in quantum and classical molecular dynamics, related techniques, and their applications to several fields of science and engineering. Molecular simulations include a broad range of methodologies such as Monte Carlo, Brownian dynamics, lattice dynamics, and molecular dynamics (MD). Features of this book: • Presents advances in methodologies, introduces quantum methods and lists new techniques for classical MD • Deals with complex systems: biomolecules, aqueous solutions, ice and clathrates, liquid crystals, polymers • Provides chemical reactions, interfaces, catalysis, surface phenomena and solids Although the book is not formally divided into methods and applications, the chapters are arranged starting with those that discuss new algorithms, methods and techniques, followed by several important applications.

Download or read book Liquid Crystals and their Computer Simulations written by Claudio Zannoni and published by Cambridge University Press. This book was released on 2022-07-28 with total page 703 pages. Available in PDF, EPUB and Kindle. Book excerpt: A comprehensive introduction to liquid crystals and their computer simulations suitable for students, researchers and industrial scientists.

Download or read book Molecular Modeling of Liquid Crystals Molecular Simulations and Statistical Mechanical Theories written by Anjali A. Khare and published by . This book was released on 1997 with total page 266 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Molecular Simulation of Cholesteric Liquid Crystal Polyesteramides written by Mercedes P√©rez M√©ndez and published by . This book was released on 2020 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Molecular modeling techniques are applied to polyesteramides designed as PNOBDME (C34H38N2O6)n and PNOBEE (C26H22N2O6)n, synthesized and characterized as cholesteric liquid crystals -through the condensation reaction between 4 and 4,Ä≤-(terephthaloyl- diaminedibenzoic chloride (NOBC) and racemic glycol: DL-1,2 dodecanediol, or DL-1,2-butanediol, respectively, being chemical modifications of precursor multifunctional cholesteric LC polyesters, adding new properties but holding their helical macromolecular structures. Although the starting raw materials were racemic, these cholesteric LC polymers exhibit unexpected optical activity and chiral morphology. For that reason, conformational analysis is studied on the monomer models of PNOBDME and PNOBEE. Four helical conformers models, experimentally observed by NMR, are proposed for each cholesteric polyesteramide: Rgg, Rgt, Sgg, Sgt. Polymerization of the monomeric conformers, with minima energies, have been simulated and used to reproduce the crystalline fraction observed by x-ray diffraction. Three orders of chirality are observed in the structure of the polymer chains: One due to the asymmetric carbon atoms, a second chirality due to the two successive rotations of the benzene groups, along the main chain, within the monomer which implies the formation of helical molecules, for both R and S chirality and still, a third chirality corresponding to the twisting of the rigid/semirigid cholesteric LC polymer chains. All these factors contributing to the net optical activity observed in these materials. Crystal packing is simulated in triclinic primitive P1cells, with molecular chains oriented parallel to the z-axis (c lattice parameter equal to the pitch length of each simulated polymer helix) and parameters a, b, Œ±, Œ≤ and Œ≥, obtained by Pawley refinement from the known structures of precursor polyesters. The simulated x-ray diffraction patterns of the proposed crystal models fit, after successive Pawley and Rietveld refinement cycles, the experimental WAXS. Powder Quantitative Phase Analysis applied to an ideal mixture with the four possible helical conformers, for each degree of polymerization, allows to refine their relative weight and determine the major phase relative amount. These results would confirm the theory of a preferable recrystallization, among the four possible helical diastereoisomers, depending on the synthetic conditions.