Download or read book Synthesis and Characterization of Salicylideneaniline Functionalized Molecular Rotors written by Ira Owen Staehle and published by . This book was released on 2014 with total page 250 pages. Available in PDF, EPUB and Kindle. Book excerpt: Artificial molecular machines have drawn much interest over the past twenty years. Several physical organic chemists have been actively involved in the study and development of different types of molecular machines. In nature many biological macromolecules have the ability to act as "molecular machines" and generate work. The most well known example of this is ATPsynthase, which functions by rotation of a central stock in order to convert ADP to ATP. These biological "molecular machines" are typically highly complex and consist of several subunits. However it is in this complexity that the function of these biological machines is manifested. In order to attain this level of complexity in artificial molecular machines, a gradual development of concepts and a deeper understanding of intermolecular interactions are required. Several molecular machine motifs have been identified and further functionality has been explored by many physical organic chemists, incorporating useful material properties. One way to create artificial molecular machines is by controlling non-brownian motion. A common motif is a system that has two distinct energy states that can interconvert between one another in response to an external stimulus. These types of molecular machine motifs can be used for generating materials that are capable of energy harnessing. Research in the Garcia-Garibay group has focused on the use of light as an external stimulus to facilitate a conformational change between two distinct states in a molecular rotor. Chapter 2 of this thesis will discuss the functionalization of molecular rotors with salicylideneanilines rotators. In work done in collaboration with Dr. Braulio Rodriguez-Molina, three different photoresponsive molecular rotors were synthesized, characterized, and crystallized. The photochromism of these solids was tested, with all systems converting from the low energy cis-enol to the transient trans-keto. The best performing of these three different molecular rotors was identified by the generation of the most trans-keto upon photoexcitation. A deuterated rotator analog was synthesized and the activation energy for rotation in the solid state was determined. Prior to this work, the preferred isomerization pathway for salicylidenenanilines was through a bicycle pedal mechanism, which does not account for rotation. The ssNMR data for the deuterated analog indicated that isomerization could also occur through rotation. Chapters 3 and 4 will discuss the functionalization of molecular rotors with salicylideneanilines stators to act as potential molecular brakes. In chapter 3, an amino substituted stator was synthesized and characterized. Crystallization proved challenging due to the preference of these compounds for the formation of spherulites, which are radial fibrous microcrystalline aggregate structures. Nonetheless, solid-state photochromism of the spherulites was determined for both systems by diffuse reflectance with the generation of a transient trans-keto form after photoexcitation. In chapter 4, an ester-substituted stator was synthesized and characterized. Single crystals could not be obtained and ssNMR was utilized to explore both the photochromism and thermochromism of the salicyladenanilines. In chapter 5 of this thesis, I will discuss the synthesis and characterization of tetra-substituted salicylideneaniline adamantanes. Adamantanes are unique because they are the simplest diamonds and provide a rigid framework with minimal stress. Furthermore, tetra-substitution of adamantane generates a tetrahedral geometry around the adamantane core. Two adamantane systems were synthesized and single crystals were grown. However, only the connectivity was determined, due to poor quality crystals. These generated molecules could have up to 64 isomers, depending on the conformations of the four salicylideneanilines moieties. The photochromism of these solids was then tested with both systems generating the transient trans-keto species.
Download or read book The Design Synthesis and Characterization of Crystalline Molecular Machines with High Structural and Dynamic Complexities written by Xing Jiang and published by . This book was released on 2016 with total page 224 pages. Available in PDF, EPUB and Kindle. Book excerpt: Molecular machines are molecular and supramolecular entities capable of producing quasi-mechanical movements. While many examples of functional artificial molecular machines have been studied in solution, crystalline aggregates of molecular machines have been explored infrequently because of the limited freedom of motion in closely packed solids. Although previous work on amphidynamic crystals has demonstrated that rotational dynamics in crystals could be achieved and engineered by proper structural design, the existing examples are limited to simple structures and small dynamic groups. As part of the efforts to prepare artificial molecular machines capable of performing useful work, the goals of my doctoral research were to design and synthesize crystalline molecular rotors with complex structures and explore their dynamics with solid-state NMR spectroscopy. I have prepared two shape-persistent dendritic molecular rotors with molecular weight over 2000 Da by different synthetic strategies. The molecular rotor prepared by a convergent synthesis provided crystals with a low packing density, which allowed megahertz rotation of all aromatic groups in the rotor. The softening of local environments with temperature, resulting from the dynamics of virtually all components in the crystal, led to a new concept of crystal fluidity. The divergent strategy used in the synthesis of the other macromolecular rotor made it possible to incorporate large rotator groups in the structure. When a bulky triptycene group was used, the shape-persistent rotor was able to support its kilohertz rotation in a semicrystalline sample. In order to realize faster triptycene rotations and to understand the structural elements required for effective solid-state gearing motions, I designed and prepared three pillared paddlewheel MOFs. I demonstrated that megahertz rotation of triptycene could be realized in a catenation-free framework, which offered a loose environment for the rotator. Since the rotator is in close contact only with the solvent molecules, its rotation is dictated solely by the hydrodynamic behavior of DMF and constitutes a diffusion-controlled process. As a result, the temperature dependence of observed rotation could shed light on the effective viscosity change of trapped solvents with temperature.
Download or read book Toward the Development of Molecular Devices written by Tiechao Li and published by . This book was released on 1994 with total page 240 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Design Synthesis and Characterization of Novel Functional Rod like and Disc shaped Molecules written by Wenmiao Shu and published by . This book was released on 2001 with total page 172 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Metal Organic Frameworks written by Leonard R. MacGillivray and published by John Wiley & Sons. This book was released on 2010-12-17 with total page 440 pages. Available in PDF, EPUB and Kindle. Book excerpt: Metal-organic frameworks represent a new class of materials that may solve the hydrogen storage problem associated with hydrogen-fueled vehicles. In this first definitive guide to metal-organic framework chemistry, author L. MacGillivray addresses state-of-art developments in this promising technology for alternative fuels. Providing professors, graduate and undergraduate students, structural chemists, physical chemists, and chemical engineers with a historical perspective, as well as the most up-to-date developments by leading experts, Metal-Organic Frameworks examines structure, symmetry, supramolecular chemistry, surface engineering, metal-organometallic frameworks, properties, and reactions.
Download or read book New Frontiers in Photochromism written by Masahiro Irie and published by Springer Science & Business Media. This book was released on 2013-05-27 with total page 298 pages. Available in PDF, EPUB and Kindle. Book excerpt: Photochromism is the reversible phototransformation of a chemical species between two forms having different absorption spectra. During the phototransformation not only the absorption spectra but also various physicochemical properties change, such as the refractive index, dielectric constant, oxidation/reduction potential, and geometrical structure. The property changes can be applied to photonic equipment such as erasable memory media, photo-optical switch components, and display devices. This book compiles the accomplishments of the research project titled “New Frontiers in Photochromism” supported by the Ministry of Education, Culture, Sports, Science and Technology of Japan. The project focused not only on the above-mentioned classical subjects in photochromism, such as color changes, optical memory, and optical switches, but also on fundamental physicochemical studies and unprecedented application fields that have not yet been explored in photochromism. The latter topics include light-driven mechanical motion, photocontrol of surface wettability, metal deposition on solid materials, photocontrol of chiral properties, ultrafast decoloration dyes, and femtosecond laser experiments, among others.
Download or read book Molecular Devices written by Andrei A. Gakh and published by John Wiley & Sons. This book was released on 2018-08-07 with total page 352 pages. Available in PDF, EPUB and Kindle. Book excerpt: Comprehensive look at mechanical molecular devices that mimic the behavior of man-made devices Molecular devices and molecular machines are individual molecules and molecular systems capable of providing valuable device-like functions. Many of them have distinct conventional prototypes and therefore can be identified as technomimetic molecules. The last decade has seen an increasing rate of practical applications of molecular devices and machines, primarily in biomedical and material science fields. Molecular devices: An Introduction to Technomimetics and its Biological Applications focuses on mechanical molecular devices, including the early set of technomimetic molecules. Topics covered include the many simple molecular devices such as container compounds, gearing systems, belts and tubes, and tweezers. It touches upon each molecular machine and discusses in great detail the importance of their applications as well as the latest progress in the fields of chemistry, physics, and biotechnology. Interdisciplinary: Must-have content for physicists, chemists, and biologists Comprehensive: Details an extensive set of mechanical technomimetic molecular devices Thorough: Starts with the fundamental material characterization and finishes with real-world device application Molecular devices: An Introduction to Technomimetics and its Biological Applications is an important book for graduate students, researchers, scientists, and engineers in the fields of chemistry, materials science, molecular physics, engineering, biotechnology, and molecular medicine.
Download or read book Molecular Materials written by Duncan W. Bruce and published by John Wiley & Sons. This book was released on 2011-04-04 with total page 455 pages. Available in PDF, EPUB and Kindle. Book excerpt: “... the book does an excellent job of putting together several different classes of materials. Many common points emerge, and the book may facilitate the development of hybrids in which the qualities of the “parents” are enhanced.” –Angew. Chem. Int. Ed. 2011 With applications in optoelectronics and photonics, quantum information processing, nanotechnology and data storage, molecular materials enrich our daily lives in countless ways. These materials have properties that depend on their exact structure, the degree of order in the way the molecules are aligned and their crystalline nature. Small, delicate changes in molecular structure can totally alter the properties of the material in bulk. There has been increasing emphasis on functional metal complexes that demonstrate a wide range of physical phenomena. Molecular Materials represents the diversity of the area, encapsulating magnetic, optical and electrical properties, with chapters on: Metal-Based Quadratic Nonlinear Optical Materials Physical Properties of Metallomesogens Molecular Magnetic Materials Molecular Inorganic Conductors and Superconductors Molecular Nanomagnets Structured to include a clear introduction, a discussion of the basic concepts and up-to-date coverage of key aspects, each chapter provides a detailed review which conveys the excitement of work in that field. Additional volumes in the Inorganic Materials Series: Low-Dimensional Solids | Molecular Materials | Porous Materials | Energy Materials
Download or read book Functional Polymer Coatings written by Limin Wu and published by John Wiley & Sons. This book was released on 2015-06-15 with total page 366 pages. Available in PDF, EPUB and Kindle. Book excerpt: Focusing on a variety of coatings, this book provides detailed discussion on preparation, novel techniques, recent developments, and design theories to present the advantages of each function and provide the tools for better product performance and properties. • Presents advantages and benefits of properties and applications of the novel coating types • Includes chapters on specific and novel coatings, like nanocomposite, surface wettability tunable, stimuli-responsive, anti-fouling, antibacterial, self-healing, and structural coloring • Provides detailed discussion on recent developments in the field as well as current and future perspectives • Acts as a guide for polymer and materials researchers in optimizing polymer coating properties and increasing product performance
Download or read book Organic Optoelectronic Materials written by Yongfang Li and published by Springer. This book was released on 2015-05-30 with total page 402 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume reviews the latest trends in organic optoelectronic materials. Each comprehensive chapter allows graduate students and newcomers to the field to grasp the basics, whilst also ensuring that they have the most up-to-date overview of the latest research. Topics include: organic conductors and semiconductors; conducting polymers and conjugated polymer semiconductors, as well as their applications in organic field-effect-transistors; organic light-emitting diodes; and organic photovoltaics and transparent conducting electrodes. The molecular structures, synthesis methods, physicochemical and optoelectronic properties of the organic optoelectronic materials are also introduced and described in detail. The authors also elucidate the structures and working mechanisms of organic optoelectronic devices and outline fundamental scientific problems and future research directions. This volume is invaluable to all those interested in organic optoelectronic materials.
Download or read book Physical Networks written by Walther Burchard and published by Springer Science & Business Media. This book was released on 1990-05-31 with total page 444 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Metallo Supramolecular Polymers written by Masayoshi Higuchi and published by Springer Nature. This book was released on 2019-11-12 with total page 89 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book introduces the synthesis, electrochemical and photochemical properties, and device applications of metallo-supramolecular polymers, new kinds of polymers synthesized by the complexation of metal ions and organic ditopic ligands. Their electrochemical and photochemical properties are also interesting and much different from conventional organic polymers. The properties come from the electronic intra-chain interaction between the metal ions and the ligands in the polymer chain. In this book, for example, the electrochromism that the Fe(II)-based metallo-supramolecular polymer exhibits is described: the blue color of the polymer film disappears by the electrochemical oxidation of Fe(II) ions to Fe(III) and the colorless film becomes blue again by the electrochemical reduction of Fe(III) to Fe(II). The electrochromism is explained by the disappearance/appearance of the metal-to-ligand charge transfer absorption. The electrochromic properties are applicable to display devices such as electronic paper and smart windows.
Download or read book Organic Solid State Chemistry written by Gautam R. Desiraju and published by Elsevier Publishing Company. This book was released on 1987 with total page 580 pages. Available in PDF, EPUB and Kindle. Book excerpt: With the growing recognition that many organic reactions may be conducted easily in the solid state and that organic solids may have unique optical/electronic properties, there has been much interest - in both academia and industry - in the subject of organic solid state chemistry. This book provides, for the first time, a coherent, unified view of the subject. It describes the packing of molecular crystals and how this packing influences chemical reactions in the solid state. It is concerned with various means of studying the chemistry and physics of molecules in constrained environments. Both experimental and theoretical approaches are discussed. Finally, it tackles the question of prediction of crystal packing, or crystal engineering'. The strength of the book lies in the twin approach adopted, namely that both conceptual and comprehensive chapters are present, in almost equal numbers.
Download or read book Mechanically Responsive Materials for Soft Robotics written by Hideko Koshima and published by John Wiley & Sons. This book was released on 2020-02-18 with total page 442 pages. Available in PDF, EPUB and Kindle. Book excerpt: Offers a comprehensive review of the research and development of mechanically responsive materials and their applications in soft robots Mechanically Responsive Materials for Soft Robotics offers an authoritative guide to the current state of mechanically responsive materials for the development of soft robotics. With contributions from an international panel of experts, the book examines existing mechanically responsive materials such as crystals, polymers, gels, and composites that are stimulated by light and heat. The book also explores the application of mechanical materials to soft robotics. The authors describe the many excellent mechanical crystals developed in recent years that show the ability to bend, twist, rotate, jump, self-heal, and shape memory. Mechanical polymer materials are described for evolution into artificial muscles, photomobile materials, bioinspired soft actuators, inorganic-organic hybrid materials, multi-responsive composite materials, and strain sensor materials. The application of mechanical materials to soft robots is just the beginning. This book reviews the many challenging and versatile applications, such as soft microrobots made from photoresponsive elastomers, four-dimensional printing for assembling soft robots, self-growing of soft robots like plants, and biohybrid robots using muscle tissue. This important book: -Explores recent developments in the use of soft smart materials in robotic systems -Covers the full scope of mechanically responsive materials: polymers, crystals, gels, and nanocomposites -Deals with an interdisciplinary topic of advanced smart materials research -Contains extensive descriptions of current and future applications in soft robotics Written for materials scientists, polymer chemists, photochemists, physical chemists, solid state chemists, inorganic chemists, and robotics engineers, Mechanically Responsive Materials for Soft Robotics offers a comprehensive and timely review of the most recent research on mechanically responsive materials and the manufacture of soft robotics.
Download or read book Photochromism Molecules and Systems written by Heinz Dürr and published by Elsevier. This book was released on 2003-03-12 with total page 1221 pages. Available in PDF, EPUB and Kindle. Book excerpt: Photochromism is simply defined as the light induced reversible change of colour. The field has developed rapidly during the past decade as a result of attempts to improve the established materials and to discover new devices for applications.As photochromism bridges molecular, supramolecular and solid state chemistry, as well as organic, inorganic and physical chemistry, such a treatment requires a multidisciplinary approach and a broad presentation. The first edition (1990) provided an enormous amount of new concepts and data, such as the presentation of main families based on the pericyclic reaction mechanism, the review of new families, some bimolecular photocycloadditions and some promising systems. This new edition provides an efficient entry into this flourishing field, with the core content retained from the original work to provide a basic introduction into the different subjects. *Second edition of a work first published in 1990, now revised due to constant development of research. *Including updated lists of references (1989-2001), offering immediate access to recent developments.*Providing great basic interest and high application potential bringing scientists together from chemistry, physics and engineering.
Download or read book Gene and Cell Therapy Biology and Applications written by Giridhara R. Jayandharan and published by Springer. This book was released on 2018-09-12 with total page 316 pages. Available in PDF, EPUB and Kindle. Book excerpt: Recent advances in stem cell biology, nanotechnology and gene therapy have opened new avenues for therapeutics. The availability of molecular therapeutics that rely on the delivery of DNA, RNA or proteins, harnessing enhanced delivery with nanoparticles, and the regenerative potential of stem cells (adult, embryonic or induced pluripotent stem cells) has had a tremendous impact on translational medicine. The chapters in this book cover a range of strategies for molecular and cellular therapies for human disease, their advantages, and central challenges to their widespread application. Potential solutions to these issues are also discussed in detail. Further, the book addresses numerous advances in the field of molecular therapeutics that will be of interest to the general scientific community. Lastly, the book provides specific examples of disease conditions for which these strategies have been transferred to the clinic. As such, it will be extremely useful for all students, researchers and clinicians working in the field of translational medicine and molecular therapeutics.
Download or read book Molecular Networks written by Mir Wais Hosseini and published by Springer Science & Business Media. This book was released on 2009-06-29 with total page 173 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the future, many modern materials will be increasingly based on the assembly of preformed molecular entities. Their structural characteristics and functional prop- ties will be programmed at the molecular level and their formation as a completed entity will be achieved by self-assembly processes. This in essence is a bottom-up approach and its success will require a deep understanding not only of the chemistry of intermolecular interactions and associations but also of self-assembly processes in the condensed phase. Among various interesting innovations brought about by the development of supramolecular chemistry, supramolecular synthesis is a part- ularly powerful approach for the design and generation of molecular architectures displaying both structural and functional complexity. The combination of mol- ular synthesis (which allows chemists to design and prepare extremely sophis- cated biotic and abiotic molecules through the interconnection of atoms or group of atoms by strong covalent bonds) and supramolecular synthesis (which orch- trates the association of molecules by recognition processes through the use of weak and reversible interactions) opens up endless structural and functional possibilities. Following the perceptive observation by Dunitz that "A crystal is, in a sense, the supramolecule par excellence", molecular crystals may be seen as in'nite periodic architectures resulting from the interconnection of building blocks or tectons ca- ble of self-assembling through speci'c recognising events.
