Download or read book Substituent Effects on Exchange Coupling Controlling the Interactions Between Unpaired Electrons written by and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Design, synthesis, and characterization of novel high-spin species are critical for advancing the field of molecular magnetism, and subsequently creating new magnetic materials. As a means of grasping an understanding of how it is that one can control the electronic, hence magnetic interactions within a high-spin species, this study focuses on structure- property relationships in a series of bis(semiquinone) biradicals. The biradical moiety is the simplest of exchange-coupled systems. As electron-withdrawing, -donating and neutral substituents are placed on the coupler or spin carrier fragment of the biradicals under study, it is shown that there is a substituent effect operating within the series of ferromagnetically coupled m-phenylene bis(semiquinone) moieties.
Download or read book Substituent Effects on Exchange Coupling written by Tashni-Ann Coote and published by . This book was released on 2006 with total page 139 pages. Available in PDF, EPUB and Kindle. Book excerpt: Keywords: Biradicals, Magnetism, Exchange Coupling, Substituent Effect, Semiquinone.
Download or read book Substituent Effects on Spin Density Distribution and Exchange Coupling in Semiquinone Complexes written by and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Substituent Effects on Spin Density Distribution and Exchange Coupling in Semiquinone Complexes written by Joseph C. Sloop and published by . This book was released on 2003 with total page 172 pages. Available in PDF, EPUB and Kindle. Book excerpt: Keywords: exchange coupling, electrochemistry, magnetometry, Hammett correlation, Semiquinone, spin density.
Download or read book Electronic Studies of High Spin Organic Molecules From the Effects of Substituents on Exchange Coupling to New Heterospin Species written by and published by . This book was released on 2002 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Design, synthesis, and characterization of novel high-spin species are critical in better understanding the field of molecular magnetism. It is also critical in advancing the field to a level of application, where new magnetic materials can be used in daily life. In this work, structure-property relationships of bis(semiquinone)s (SQ's) were studied, substituent effects on exchange coupling were investigated, and a series of novel, heterospin, complexes were synthesized and characterized. A strong comparison of exchange coupling to mixed valency is made in a bis(SQ) based on magnetic and electrochemistry data. This comparison is possible because of the isostructural species involved in the study, a Trimethylenemethane-Type (TMM) coupled bis(SQ), and a similarly mediated mixed-valent species. The sole difference between the two species being a single electron. A substituent effect was found to operate in an isostructural series of three meta-phenylene-Type (MPH), ferromagnetically coupled bis(SQ)s. Using common electron donating, withdrawing, and 'neutral' substituents, (NMe2, NO2, and t-Bu respectively) it was shown that both donating and withdrawing groups attenuate the singlet-triplet gap in the ground-state triplet species. A relatively simple HÜckle molecular orbital explanation describes the effect. It is the first time that a singlet-triplet gap of a ground-state triplet biradical has been affected by substituents. Finally, a series of new heterospin complexes consisting of a nitronyl nitroxide (NN), semiquinone (SQ), and metal (II) ion were synthesized and characterized. These species are among the limited few examples of a molecular species containing up to three entirely different spin-carriers. Also, of great importance, is the novel variation on the TMM-type coupling within the complexes. This ferromagnet coupling between the nitronyl nitroxide and the semiquinone portions of the complex is so strong (lower limit of + 310 cm−1).
Download or read book Substituent Effects on the Spin exchange Interaction in Flexible Organic Biradicals written by Jonathan David Ball and published by . This book was released on 1997 with total page 304 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Structural Effects on Electronic Exchange Coupling in Bis arylnitrene Systems written by Christopher Ling and published by . This book was released on 1994 with total page 374 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Redox Active Ligands written by Marine Desage-El Murr and published by John Wiley & Sons. This book was released on 2024-02-05 with total page 373 pages. Available in PDF, EPUB and Kindle. Book excerpt: Redox-Active Ligands Authoritative resource showcasing a new family of ligands that can lead to better catalysts and promising applications in organic synthesis Redox-Active Ligands gives a comprehensive overview of the unique features of redox-active ligands, describing their structure and synthesis, the characterization of their coordination complexes, and important applications in homogeneous catalysis. The work reflects the diversity of the subject by including ongoing research spanning coordination chemistry, organometallic chemistry, bioinspired catalysis, proton and electron transfer, and the ability of such ligands to interact with early and late transition metals, lanthanides, and actinides. The book is divided into three parts, devoted to introduction and concepts, applications, and case studies. After the introduction on key concepts related to the field, and the different types of ligands and complexes in which ligand-centered redox activity is commonly observed, mechanistic and computational studies are described. The second part focuses on catalytic applications of redox-active complexes, including examples from radical transformations, coordination chemistry and organic synthesis. Finally, case studies of redox-active guanidine ligands, and of lanthanides and actinides are presented. Other specific sample topics covered include: An overview of the electronic features of redox-active ligands, covering their historical perspective and biological background The versatility and mode of action of redox-active ligands, which sets them apart from more classic and tunable ligands such as phosphines or N-heterocyclic carbenes Preparation and catalytic applications of complexes of stable N-aryl radicals Metal complexes with redox-active ligands in H+/e- transfer transformations By providing up-to-date information on important concepts and applications, Redox-Active Ligands is an essential reading for researchers working in organometallic and coordination chemistry, catalysis, organic synthesis, and (bio)inorganic chemistry, as well as newcomers to the field.
Download or read book Facets of Coordination Chemistry written by B. V. Agarwala and published by World Scientific. This book was released on 1993 with total page 282 pages. Available in PDF, EPUB and Kindle. Book excerpt: A concise account of coordination chemistry since its inception is given here together with some of the newer significant facets. This book covers a broad spectrum of various topics on Environment, Cyclic Voltammetry, Chromatography, Metal Complexes of biological interest, Alkoxides, NMR spectroscopy and others. These are useful to the scientific community engaged in the field of Inorganic Chemistry and Analytical Chemistry.
Download or read book Multinuclear NMR written by J. Mason and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 642 pages. Available in PDF, EPUB and Kindle. Book excerpt: With the power and range of modern pulse spectrometers the compass of NMR spec troscopy is now very large for a single book-but we have undertaken this. Our book covers the Periodic Table as multinuclear spectrometers do, and introductory chapters are devoted to the essentials of the NMR experiment and its products. Primary products are chemical shifts (including anisotropies), spin-spin coupling constants, and relaxation times; the ultimate product is a knowledge of content and constitution, dynamic as well as static. Our province is chemical and biochemical rather than physical or technical; only passing reference is made to metallic solids or unstable species, or to practical NMR spectroscopy. Our aim is depth as well as breadth, to explain the fundamental processes, whether of nuclear magnetic shielding, spin-spin coupling, relaxation, or the multiple pulse sequences that have allowed the development of high-resolution studies of solids, multidimensional NMR spectroscopy, techniques for sensitivity enhancement, and so on. This book therefore combines the functions of advanced textbook and reference book. For reasonably comprehensive coverage in a single volume we have sum marized the information in tables and charts, and included all leading references.
Download or read book Substituent Effects on the Geminal Coupling Constant in an Allylic Methylene Group written by Bruce F. Raby and published by . This book was released on 1970 with total page 128 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Organic Reaction Mechanisms 1993 written by A. C. Knipe and published by John Wiley & Sons. This book was released on 2008-04-30 with total page 635 pages. Available in PDF, EPUB and Kindle. Book excerpt: The only book series to summarize the latest progress on organic reaction mechanisms, Organic Reaction Mechanisms, 1993 surveys the development in understanding of the main classes of organic reaction mechanisms reported in the primary scientific literature in 1993. The 29th annual volume in this highly successful series highlights mechanisms of stereo-specific reactions. Reviews are compiled by a team of experienced editors and authors, allowing advanced undergraduates, graduate students, postdocs, and chemists to rely on the volume's continuing quality of selection and presentation.
Download or read book Substituent Effects on Chemical Shifts and Geminal Coupling Constants of Benzylic Protons written by Roger N. Renaud and published by . This book was released on 1970 with total page 250 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book EPR of Free Radicals in Solids written by Anders Lund and published by Springer Science & Business Media. This book was released on 2013-06-29 with total page 649 pages. Available in PDF, EPUB and Kindle. Book excerpt: EPR of Free Radicals in Solids: Trends in Methods and Applications presents methods and applications of modern EPR for the study of free radical processes in solids, which so far are only available in the journal literature. The first part of the book, covering trends in methods, contains experimentally oriented chapters on continuous wave and pulsed EPR techniques and special methods involving muon magnetic resonance and optical detection and theory for dynamic studies. New simulation schemes, including the influence of dynamics, are presented as well as advances in the calculation of hyperfine and electronic g-tensors. The second part of the book presents applications involving studies of radiation and photo-induced inorganic and organic radicals in inert matrices, including novel results of quantum effects in small radicals. High-spin molecules and complexes are also considered as well as radical processes in photosynthesis. Recent advances in EPR dosimetry are summarized.
Download or read book Nuclear Magnetic Resonance written by G A Webb and published by Royal Society of Chemistry. This book was released on 2007-10-31 with total page 587 pages. Available in PDF, EPUB and Kindle. Book excerpt: As a spectroscopic method, nuclear magnetic resonance (NMR) has seen spectacular growth, both as a technique and in its applications. Today's applications of NMR span a wide range of scientific disciplines, from physics to biology to medicine. Each volume of Nuclear Magnetic Resonance comprises a combination of annual and biennial reports which together provide comprehensive coverage of the literature on this topic. This Specialist Periodical Report reflects the growing volume of published work involving NMR techniques and applications, in particular NMR of natural macromolecules, which is covered in two reports: NMR of Proteins and Nucleic Acids; and NMR of Carbohydrates, Lipids and Membranes. For those wanting to become rapidly acquainted with specific areas of NMR, Nuclear Magnetic Resonance provides unrivalled scope of coverage. Seasoned practitioners of NMR will find this an invaluable source of current methods and applications. Specialist Periodical Reports provide systematic and detailed review coverage in major areas of chemical research. Compiled by teams of leading experts in their specialist fields, this series is designed to help the chemistry community keep current with the latest developments in their field. Each volume in the series is published either annually or biennially and is a superb reference point for researchers. www.rsc.org/spr
Download or read book Crystal Engineering From Molecules and Crystals to Materials written by Dario Braga and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 502 pages. Available in PDF, EPUB and Kindle. Book excerpt: Crystal engineering is an interdisciplinary area that cuts across the traditional subdivisions of chemistry. Fuelled by our increasingly precise understanding of the chemistry and properties of supramolecular systems, interest in the potential of the field has increased rapidly. The topics discussed in the 28 contributions in this book provide a state-of-the-art description of the field and offer new research ideas that, if pursued, will serve to strengthen the field at the interface between supramolecular chemistry and materials science.
Download or read book Lanthanide Single Molecule Magnets written by Jinkui Tang and published by Springer. This book was released on 2015-04-24 with total page 219 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book begins by providing basic information on single-molecule magnets (SMMs), covering the magnetism of lanthanide, the characterization and relaxation dynamics of SMMs and advanced means of studying lanthanide SMMs. It then systematically introduces lanthanide SMMs ranging from mononuclear and dinuclear to polynuclear complexes, classifying them and highlighting those SMMs with high barrier and blocking temperatures – an approach that provides some very valuable indicators for the structural features needed to optimize the contribution of an Ising type spin to a molecular magnet. The final chapter presents some of the newest developments in the lanthanide SMM field, such as the design of multifunctional and stimuli-responsive magnetic materials as well as the anchoring and organization of the SMMs on surfaces. In addition, the crystal structure and magnetic data are clearly presented with a wealth of illustrations in each chapter, helping newcomers and experts alike to better grasp ongoing trends and explore new directions. Jinkui Tang is a professor at Changchun Institute of Applied Chemistry, Chinese Academy of Sciences. Peng Zhang is currently pursuing his PhD at Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, with a specific focus on the molecular magnetism of lanthanide compounds under the supervision of Prof. Jinkui Tang.
