Download or read book Uranyl Complexes with Nitrogen and Sulfur Donor Bidentate Ligands a Computational Modeling of Coordination Geometries Thermodynamic Parameters and Ligand Substituent Effects written by Patrick Bailey Hogsed and published by . This book was released on 2021 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Actinides represent a special group of metal ions that need to be extensively studied due to their presence in the environment with the construction of nuclear power plants, processing of minerals, and weapon production. Radioactive waste produced by nuclear fission contains several lanthanide and actinide metals, including uranium. The extraction of uranium from nuclear waste is an active area of research. To this end, numerous sulfur and nitrogen-donor ligands have been studied to assist with the nuclear extraction process. Computational chemistry investigations of actinide complexes will provide important insight into metal-ligand bonding and their thermodynamic properties in order to design effective actinide extracting agents. Current research work is focused on studying the coordination chemistry behavior and reaction energetics of a series of uranyl metal complexes with ethylenediamine, 1,2-ethanedithiol, and cysteamine ligands using density functional theory (DFT). Coordination preferences using nitrogen and sulfur-based chelation were evaluated in the gas phase. Nitrogen donor ethylenediamine ligand produced the lowest reaction Gibbs free energies, and sulfur donor cysteamine ligands had the highest values. Ligand substitution effects on uranyl metal-ligand bonding were studied using four substituent groups, CH3, CN, OCH3, and Cl. Electron donor CH3 and OCH3 groups provided relatively shorter metal-ligand bond distances and lower reaction Gibbs free energies. Electron withdrawing substituents resulted in longer metal-ligand bonding and higher reaction Gibbs free energies. Disubstitution of the chelating ligands amplifies the above effects. Future work will focus on exploring more substituents and solvent effects on uranyl metal-ligand complexation reaction using the above ligands.
Download or read book Reactivity and Electronic Structures of Uranium Complexes with Nitrogen and Oxygen Donors in Axial Symmetries written by Kimberly C. Mullane and published by . This book was released on 2017 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The effects of the ligand field are generally on the same order of magnitude as spin-orbit coupling for uranium complexes. However, significant impacts on the electronic structure, reactivity, and stability of uranium complexes have been observed as a result of changing the ligand framework. In the work presented here, uranium complexes in a variety of ligand frameworks are synthesized, and their unique electronic structures and reactivities are studied. Uranium imido complexes with varying substitution at the imido nitrogen are contrasted with uranium oxo complexes, showing that their ability to impart an inverse trans influence, a thermodynamic phenomenon in which strong donor ligands gain stability from trans axial geometries, was comparable. We also synthesized uranium complexes with a weakly donating phosphino-anilide ancillary ligand. This ligand stabilized the uranium (III/IV) couple and allowed the synthesis of a rare uranium (IV) parent imido moiety. In contrast, the bis(trimethysilyl)amide ligand framework resulted in more reducing complexes and afforded reactivity in which reactive amide radical anions could be stabilized, and other carbonyl functional groups were reduced. In this same ancillary ligand framework, we synthesized uranium (VI) oxo phenyl(acetylide) complexes and observed that distal para aryl substituents could affect covalency in U-C bonding.
Download or read book Synthesis Characterization and Structure of a Uranyl Complex with a Disulfide Ligand Bis di n propylammonium Disulfidobis di n propylthiocarbamato dioxouranate VI written by and published by . This book was released on 1982 with total page 4 pages. Available in PDF, EPUB and Kindle. Book excerpt: Olive green crystals of the title compound, [(n-C3H7)2NH2+]2[UO2((n-C3H7)2NCOS)2(S2)]2-, are orthorhombic, space group Pcan, with a = 15.326 (6) Å, b = 17.474 (6) Å, c = 14.728 (6) Å, and Z = 4 (dx = 1.45 g/cm3). For 1833 data, I > ?, R= 0.052, and Rw = 0.069. In this paper, the structure was revealed by single-crystal X-ray diffraction studies to consist of [(n-C3H7)2NH2]+ cations and [UO2((n-C3H7)2NCOS)2(S2)]2- anions with the uranium atom at the center of an irregular hexagonal bipyramid. The uranyl oxygen atoms occupy the axial positions. The equatorial coordination plane contains the disulfide (S22-) group bonded in a "side-on" fashion and two oxygen and two sulfur donor atoms from the mono-thiocarbamate ligands. Interatomic distances are S-S = 2.05 (1) Å and U-S = 2.711 (3) Å (disulfide), U-S = 2.873 (3) Å and U-O = 2.48 (1) Å (thiocarbamate), and U-O = 1.82 (1) Å (uranyl). Finally, the nitrogen atom in the dipropylammonium cation is hydrogen bonded to the uranyl oxygen atoms.
Download or read book Machine Learning in Chemistry written by Jon Paul Janet and published by American Chemical Society. This book was released on 2020-05-28 with total page 189 pages. Available in PDF, EPUB and Kindle. Book excerpt: Recent advances in machine learning or artificial intelligence for vision and natural language processing that have enabled the development of new technologies such as personal assistants or self-driving cars have brought machine learning and artificial intelligence to the forefront of popular culture. The accumulation of these algorithmic advances along with the increasing availability of large data sets and readily available high performance computing has played an important role in bringing machine learning applications to such a wide range of disciplines. Given the emphasis in the chemical sciences on the relationship between structure and function, whether in biochemistry or in materials chemistry, adoption of machine learning by chemistsderivations where they are important
Download or read book Mechanistic Study of Nitrogen sulphur Donor Atom Bidentate Ligand Influence on the Iodomethane Oxidative Addition to Carbonylphosphinerhodium I Complexes written by Gideon Jacobus Joubert Steyn and published by . This book was released on 1994 with total page 181 pages. Available in PDF, EPUB and Kindle. Book excerpt:
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.
Download or read book Metal Complexes in Aqueous Solutions written by Arthur E. Martell and published by Springer Science & Business Media. This book was released on 2013-06-29 with total page 259 pages. Available in PDF, EPUB and Kindle. Book excerpt: Stability constants are fundamental to understanding the behavior of metal ions in aqueous solution. Such understanding is important in a wide variety of areas, such as metal ions in biology, biomedical applications, metal ions in the environment, extraction metallurgy, food chemistry, and metal ions in many industrial processes. In spite of this importance, it appears that many inorganic chemists have lost an appreciation for the importance of stability constants, and the thermodynamic aspects of complex formation, with attention focused over the last thirty years on newer areas, such as organometallic chemistry. This book is an attempt to show the richness of chemistry that can be revealed by stability constants, when measured as part of an overall strategy aimed at understanding the complexing properties of a particular ligand or metal ion. Thus, for example, there are numerous crystal structures of the Li+ ion with crown ethers. What do these indicate to us about the chemistry of Li+ with crown ethers? In fact, most of these crystal structures are in a sense misleading, in that the Li+ ion forms no complexes, or at best very weak complexes, with familiar crown ethers such as l2-crown-4, in any known solvent. Thus, without the stability constants, our understanding of the chemistry of a metal ion with any particular ligand must be regarded as incomplete. In this book we attempt to show how stability constants can reveal factors in ligand design which could not readily be deduced from any other physical technique.
Download or read book Supramolecular Chemistry in the 3rd Millennium written by Catherine E. Housecroft and published by MDPI. This book was released on 2021-08-18 with total page 264 pages. Available in PDF, EPUB and Kindle. Book excerpt: This Special Issue is one of the first for the new MDPI flagship journal Chemistry (ISSN 2624-8549) which has a broad remit for publishing original research in all areas of chemistry. The theme of this issue is Supramolecular Chemistry in the 3rd Millennium and I am sure that this topic will attract many exciting contributions. We chose this topic because it encompasses the unity of contemporary pluridisciplinary science, in which organic, inorganic, physical and theoretical chemists work together with molecular biologists and physicists to develop a systems-level understanding of molecular interactions. The description of supramolecular chemistry as 'chemistry beyond the molecule' (Jean-Marie Lehn, Nobel Lecture and Gautam R. Desiraju, Nature, 2001, 412, 397) addresses the wide variety of weak, non-covalent interactions that are the basis for the assembly of supramolecular architectures, molecular receptors and molecular recognition, programed molecular systems, dynamic combinatorial libraries, coordination networks and functional supramolecular materials. We welcome submissions from all disciplines involved in this exciting and evolving area of science.
Download or read book Comprehensive Coordination Chemistry II written by J. A. McCleverty and published by Newnes. This book was released on 2003-12-03 with total page 11845 pages. Available in PDF, EPUB and Kindle. Book excerpt: Comprehensive Coordination Chemistry II (CCC II) is the sequel to what has become a classic in the field, Comprehensive Coordination Chemistry, published in 1987. CCC II builds on the first and surveys new developments authoritatively in over 200 newly comissioned chapters, with an emphasis on current trends in biology, materials science and other areas of contemporary scientific interest.
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 Surface Organometallic Chemistry Molecular Approaches to Surface Catalysis written by Jean-Marie Basset and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 340 pages. Available in PDF, EPUB and Kindle. Book excerpt: Surface organometallic chemistry is a new field bringing together researchers from organometallic, inorganic, and surface chemistry and catalysis. Topics ranging from reaction mechanisms to catalyst preparation are considered from a molecular basis, according to which the "active site" on a catalyst surface has a supra-molecular character. This. the first book on the subject, is the outcome of a NATO Workshop held in Le Rouret. France, in May. 1986. It is our hope that the following chapters and the concluding summary of recommendations for research may help to provide a definition of surface organometallic chemistry. Besides catalysis. the central theme of the Workshop, four main topics are considered: 1) Reactions of organometallics with surfaces of metal oxides, metals. and zeolites; 2) Molecular models of surfaces, metal oxides, and metals; 3) Molecular approaches to the mechanisms of surface reactions; 4) Synthesis and modification of zeolites and related microporous solids. Most surface organometallic chemistry has been carried out on amorphous high-surf ace-area metal oxides such as silica. alumina. magnesia, and titania. The first chapter. contributed by KNOZINGER. gives a short summary of the structure and reactivity of metal oxide surfaces. Most of our understanding of these surfaces is based on acid base and redox chemistry; this chemistry has developed from X-ray and spectroscopic data, and much has been inferred from the structures and reactivities of adsorbed organic probe molecules. There are major opportunities for extending this understanding by use of well-defined (single crystal) oxide surfaces and organometallic probe molecules.
Download or read book Infrared and Raman Spectra of Inorganic and Coordination Compounds Part A written by Kazuo Nakamoto and published by John Wiley & Sons. This book was released on 2008-12-22 with total page 350 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Sixth Edition of this classic work comprises the most comprehensive and current guide to infrared and Raman spectra of inorganic, organometallic, bioinorganic, and coordination compounds. From fundamental theories of vibrational spectroscopy to applications in a variety of compound types, this has been extensively updated. New topics include the theoretical calculations of vibrational frequencies (DFT method), chemical synthesis by matrix co-condensation reactions, time-resolved Raman spectroscopy, and more. This volume is a core reference for chemists and medical professionals working with infrared or Raman spectroscopies and an excellent textbook for graduate courses.
Download or read book Modern Organonickel Chemistry written by Yoshinao Tamaru and published by John Wiley & Sons. This book was released on 2006-03-06 with total page 346 pages. Available in PDF, EPUB and Kindle. Book excerpt: Organonickel chemistry plays an increasingly important role in organic chemistry, and interest in this topic is now just as keen as in organopalladium chemistry. While there are numerous, very successful books on the latter, a book specializing in organonickel chemistry is long overdue. Edited by one of the leading experts in the field, this volume covers the many discoveries made over the past 30 years, and previously scattered throughout the literature. Active researchers working at the forefront of organonickel chemistry provide a comprehensive review of the topic, including cross-coupling reactions, asymmetric synthesis and heterogeneous catalysis reaction types. A must-have for both organometallic chemists and synthetic organic chemists.
Download or read book Handbook of Pyrrolidone and Caprolactam Based Materials 6 Volume Set written by Osama M. Musa and published by John Wiley & Sons. This book was released on 2021-07-06 with total page 2665 pages. Available in PDF, EPUB and Kindle. Book excerpt: HANDBOOK OF PYRROLIDONE AND CAPROLACTAM BASED MATERIALS Brings together, for the first time, a comprehensive review of all aspects of pyrrolidone- and caprolactam-based materials This comprehensive, six-volume set describes the broad technical universe of γ- and ε- lactams, reviewing in-depth the chemistry of the small lactam-based molecules, uncovering their unique properties and showing how they have enabled a myriad of commercially important applications. From synthesis, through production and into applications, this extensive work targets significant and recent trends in γ- and ε-lactam science and technology and addresses all key aspects of pyrrolidone- and caprolactam-based materials to produce a definitive overview of the field. Handbook of Pyrrolidone and Caprolactam Based Materials provides a detailed and modern portrait of the impact of pyrrolidone- and caprolactam-based materials on the world, as well as potential future possibilities. Volume One presents the chemistry of small lactam-based molecules and uncovers their unique properties. Volume Two covers polymeric materials, including polyvinyl pyrrolidone and polyvinyl caprolactam, and reviews homopolymerization, copolymerization, controlled radical polymermization and acrylate based pyrrolidone polymerizations. Volume Three examines the physical chemistry and molecular interactions of pyrrolidone and caprolactam based materials. Volume Four expands upon the characterization theme from the third volume, and includes detailed discussions of nuclear magnetic resonance (NMR) and Fourier transform-infrared (FT-IR) spectroscopy, thermal and mechanical properties, and imaging techniques. Volume Five explores pharmaceutical applications in both ingredients and materials, as well as the antimicrobial properties and applications of pyrrolidone and caprolactam-based materials, and their toxicology. Volume Six covers personal and home care, skin care, transdermal applications and wound care, oral care, adhesion related applications and digital applications such as inkjet technology. Handbook of Pyrrolidone and Caprolactam Based Materials will appeal to industrial scientists and engineers interested in polymer development and manufacturing. It will also benefit academic researchers working in the fields of chemistry, materials science, and chemical and process engineering.
Download or read book Core Concepts in Supramolecular Chemistry and Nanochemistry written by Jonathan W. Steed and published by John Wiley & Sons. This book was released on 2007-04-30 with total page 320 pages. Available in PDF, EPUB and Kindle. Book excerpt: Supramolecular chemistry and nanochemistry are two strongly interrelated cutting edge frontiers in research in the chemical sciences. The results of recent work in the area are now an increasing part of modern degree courses and hugely important to researchers. Core Concepts in Supramolecular Chemistry and Nanochemistry clearly outlines the fundamentals that underlie supramolecular chemistry and nanochemistry and takes an umbrella view of the whole area. This concise textbook traces the fascinating modern practice of the chemistry of the non-covalent bond from its fundamental origins through to it expression in the emergence of nanochemistry. Fusing synthetic materials and supramolecular chemistry with crystal engineering and the emerging principles of nanotechnology, the book is an ideal introduction to current chemical thought for researchers and a superb resource for students entering these exciting areas for the first time. The book builds from first principles rather than adopting a review style and includes key references to guide the reader through influential work. supplementary website featuring powerpoint slides of the figures in the book further references in each chapter builds from first principles rather than adopting a review style includes chapter on nanochemistry clear diagrams to highlight basic principles
Download or read book Chemical Thermodynamics of Uranium written by Ingmar Grenthe and published by Elsevier Science & Technology. This book was released on 1992 with total page 744 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume provides a comprehensive overview on the chemical thermodynamics of those elements that are of particular importance in the safety assessment of radioactive waste disposal systems. This is the first volume in a series of critical reviews to be published on this subject. The book provides an extensive compilation of chemical thermodynamic data for uranium. A description of procedures for activity corrections and uncertainty estimates is given. A critical discussion of data needed for nuclear waste management assessments, including areas where significant gaps of knowledge exist is presented. A detailed inventory of chemical thermodynamic data for inorganic compounds and complexes of uranium is listed. Data and their uncertainty limits are recommended for 74 aqueous complexes and 199 solid and 31 gaseous compounds containing uranium, and on 52 aqueous and 17 solid auxiliary species containing no uranium. The data are internally consistent and compatible with the CODATA Key Values. The book contains a detailed discussion of procedures used for activity factor corrections in aqueous solution, as well as including methods for making uncertainty estimates.
Download or read book Recent Advances in Density Functional Methods written by Delano Pun Chong and published by World Scientific. This book was released on 1995 with total page 344 pages. Available in PDF, EPUB and Kindle. Book excerpt: Of all the different areas in computational chemistry, density functional theory (DFT) enjoys the most rapid development. Even at the level of the local density approximation (LDA), which is computationally less demanding, DFT can usually provide better answers than Hartree-Fock formalism for large systems such as clusters and solids. For atoms and molecules, the results from DFT often rival those obtained by ab initio quantum chemistry, partly because larger basis sets can be used. Such encouraging results have in turn stimulated workers to further investigate the formal theory as well as the computational methodology of DFT.This Part II expands on the methodology and applications of DFT. Some of the chapters report on the latest developments (since the publication of Part I in 1995), while others extend the applications to wider range of molecules and their environments. Together, this and other recent review volumes on DFT show that DFT provides an efficient and accurate alternative to traditional quantum chemical methods. Such demonstration should hopefully stimulate frutiful developments in formal theory, better exchange-correlation functionals, and linear scaling methodology.
