Download or read book Synthesis Electronic Delocalization and Applications of Octahedral Bis imino pyridine Group 13 Metal Complexes written by Amela Arnold (Drljevic) and published by . This book was released on 2020 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation discusses the synthesis, characterization and electronic delocalization of bis(imino)pyridine (I2P) complexes of the Group 13 metals Al, Ga and In. This work aims to understand the electronic communication between redox-active ligands bridged by a main group metal and apply this research for storing multiple electrons in nonaqueous redox-flow battery applications. The introduction to this dissertation details the background on redox-active ligands, mixed valency and redox flow batteries. A future outlook on this field is presented. The work presented here has contributed to our understanding of delocalization of charge in organic molecules, and how delocalization is affected by increasing charge, appending electron-donating or withdrawing functional groups or varying the metal bridge. Evidence for a symmetric nonaqueous redox flow battery is presented. In Chapter 2, ligand-based mixed valency is introduced. Water stable organic mixed valence (MV) compounds were prepared by reaction of reduced bis(imino)pyridine ligands (I2P) with the trichloride salts of Al, Ga, and In. Coordination of two tridentate ligands to each ion affords octahedral complexes that are accessible with five ligand charge states: [(I2P0)(I2P−)M]2+, [(I2P−)2M]+, (I2P−)(I2P2−)M, [(I2P2−)2M]−, [(I2P2−)(I2P3−)M]2−, and for M = Al only, [(I2P3−)2M]3−. In solid-state structures the anionic members of the redox series are stabilized by intercalation of Na+ cations within the ligands. The MV members of the redox series, (I2P−)(I2P2−)M and [(I2P2−)(I2P3−)M]2−, show characteristic intervalence transitions, in the near-infrared region between 6800 - 7400 and 7800 - 9000 cm-1, respectively. Cyclic voltammetry (CV), NIR spectroscopic, and X-ray structural studies support the assignment of Class II for compounds [(I2P2−)(I2P3−)M]2− and Class III for M = Al and Ga in (I2P−)(I2P2−)M. All compounds containing a singly reduced I2P− ligand exhibit a sharp, low energy transition in the region 5100 - 5600 cm−1 that corresponds to a [pi]* - [pi]* transition. CV studies demonstrate that the electron transfer events in each of the redox series, Al, Ga, and In span 2.2, 1.4 and 1.2 V, respectively. In Chapter 3, ligand-based mixed valent (MV) complexes of Al(III) incorporating electron donating (ED) and electron withdrawing (EW) substituents on bis(imino)pyridine ligands (I2P) are presented. The MV states (I2P−)(I2P2−)Al and [(I2P2−)(I2P3−)Al]2− prepared containing EW groups are both assigned as Class II/III. The MV states prepared with incorporation of ED functional groups are Class III and Class II/III in the (I2P−)(I2P2−)Al and [(I2P2−)(I2P3−)Al]2− charge states, respectively. The assignments of the delocalized electronic structures were made using cyclic voltammetry (CV), and near infra-red (NIR) spectroscopy. The MV ligand charge states (I2P−)(I2P2−)Al and [(I2P2−)(I2P3−)Al]2− show intervalence charge transfer (IVCT) transitions at 6850-7740 and 7410-9780 cm−1, respectively. Alkali metal cations in solution had no effect on the IVCT bands of [(I2P2−)(I2P3−)Al]2− complexes containing ED -PhNMe2 substituents or EW -PhF5 substituents on the I2P ligands. Localization of charge in [(I2P2−)(I2P3−)Al]2− was observed when -PhOMe substituents are included on the I2P ligands, so that those complexes are Class II/III with K+ and Class III with K:(18-crown-6)+. In Chapter 4, the application of these redox-active octahedral Al(III) complexes as analytes for symmetric nonaqueous redox flow batteries is presented. Redox flow batteries (RFBs) operate by storing electrons on soluble molecular anolytes and catholytes, however large increases in the energy density of RFBs could be achieved if multiple electrons could be stored in each molecular analyte. Others have suggested and employed various transition element - redox active ligands combinations to realize multi-electron storage in anolytes, and a challenge with those efforts has been the analyte's stability over extended charging and discharging of multi-electron cycles. We reported an organoaluminum analyte in which four electrons can be stored on organic ligands, and for which charging and discharging cycles performed in a symmetric nonaqueous RFB configuration remain stable for over 100 cycles at 70% state of charge and 97% Coulombic efficiency. Stability is promoted by the kinetic inertness of the anolyte to trace water in solvents and by the redox stability of the Al(III) ion to the applied current. Proof-of principle experiments performed with an asymmetric NRFB configuration further demonstrate that up to four electrons can be stored in the cell with no degradation of the analyte over multiple cycles that show 96% Coulombic efficiency.
Download or read book Bis imino pyridine Iron and Cobalt Complexes written by Amanda Catherine Bowman and published by . This book was released on 2010 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The synthesis, reactivity and electronic structures of a series of bis(imino)pyridine iron and cobalt complexes was investigated. A series of monomeric bis(imino)pyridine cobalt dinitrogen complexes was investigated using a combination of 1H NMR and infrared spectroscopies, X-ray crystallography, EPR spectroscopy, solution and solid state magnetic measurements and density functional theory. The neutral bis(imino)pyridine cobalt dinitrogen complexes have doublet ground states and are best described as low-spin cobalt(I) centers with an unpaired electron on the singly reduced chelate, while the anionic bis(imino)pyridine cobalt dinitrogen complexes are also best described as low-spin cobalt(I) centers with dianionic chelates. These investigations established that reduction of monochloride precursors occurs at the metal center, in contrast to the related bis(imino)pyridine iron bis(dinitrogen) complex, (iPrPDI)Fe(N2)2, where reduction of the chelate is observed. A series of bis(imino)pyridine iron imide complexes was also investigated. A combination of Xray crystallography, variable temperature SQUID magnetization data and Mössbauer spectroscopy was used to elucidate the electronic structures of these complexes. In contrast to the previously reported N-aryl substituted bis(imino)pyridine iron imide complexes, where an iron(III) metal center and a singly reduced chelate was observed, an iron(IV) metal center and a triplet diradical chelate was observed for N-alkyl substituted bis(imino)pyridine iron imide complexes. For (iPrPDI)FeN(2Ad) (iPrPDI = 2,6-(2,6-iPr2-C6H3-N=CMe)2C5H3N), thermal spin crossover from S = 0 to S = 1 was observed when warming from 15 K to 200 K. (ArPDI)FeNR compounds with an S = 0 ground state promoted C-H bond activation of both imine methyl groups of the bis(imino)pyridine ligand. The C-H bond activation with (iPrPDI)FeN(CyOct) was firstorder in iron with a rate constant of k = 3.4(2)x10-5 s-1 at 25 °C and a primary kinetic isotope effect of 3.3(2), consistent with a rate-determining step of intramolecular C-H bond activation. In contrast, no C-H bond activation of the ligand was observed for the iron imide complexes that are S = 1 at 23 °C. The reactivity of bis(imino)pyridine iron imide compounds with hydrogen, silanes, terminal alkynes and organic azides, and the electronic structures of the resulting iron complexes, was also investigated.
Download or read book The Facile Preparation of Bis imino pyridine Complexes Via Mechanochemistry and Inorganic Synthons Via Benign Reductants written by Thomas E. Shaw IV and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis is comprised of two key themes: (i) leveraging mechanochemical synthetic methods for the green preparation of bis(imino)pyridine ligands and associated first row transition metal coordination complexes, and (ii) the preparation and characterization of both historic and novel mid-valent inorganic synthons via the use of dimethylphenylsilane as a stoichiometric reducing agent. The first portion of this thesis highlights the utilization of solvent-free vibratory ball-milling in lieu of traditional, solvent-based refluxes. A variety of both bis(imino)pyridine ligands and complexes were formed in drastically reduced timeframes with solvent-economical work-up procedures. This methodology was also leveraged for the isolation of acetyl(imino)pyridine ligands which, in turn, provided direct access to an unsymmetrical bis(imino)pyridine ligand in good yield. The second portion of this thesis is centered on the preparation of ether-coordinated, mid-valent, early transition metal chloride precursors. First, well-established, reproducible syntheses and characterization libraries were developed for the classic molybdenum(IV) and tungsten(IV) chloride diethyl ether- and dimethoyxethane-coordinated synthons. Then, the utilization of commercially available dimethylphenylsilane as a stoichiometric reducing agent provided direct access to single crystals of the classic edge-sharing bioctahedral dimer Mo2Cl6(dme)2, whose single crystal x-ray structure and electronic structure had remained ambiguous for nearly 40 years. This work laid the foundation for the preparation of intriguingly reactive, uncoordinated, mid-valent binary chlorides of the heavier Group 5 and Group 6 transition metals. Utilization of the acquired binary chlorides resulted in both less expensive, easier routes to traditional synthons and the formation of novel, ether-coordinated complexes of niobium and tantalum. Synthesis, characterization, and computational studies are presented and discussed.
Download or read book Catalysis by Metal Complexes and Nanomaterials written by Meng Zhou (Chemistry professor) and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: "Catalysis is truly an interdisciplinary field to which chemists, biologists, physicists, and engineers have made seminal contributions. This book aims to address the notably diverse topic of transition-metal catalysis in a single volume. The first half of the book is dedicated to the discrete and atomically precise metal complexes for homogeneous catalysis. Bimetallic, organometallic, and coordination complexes of early, late, and post-transition metals are described. Catalytic hydrogenation, oxidation, and coupling reactions are presented. The second half of the book focuses on three distinct types of nanomaterials: (1) zero- valent metallic nanoparticles, (2) titanium dioxide semiconductors, and (3) the porous coordination polymer known as the metal-organic framework. The chapters illustrate how deeply catalysis is influenced by other disciplines (e.g., coordination chemistry, bioinorganic chemistry, organometallic chemistry, computational chemistry, organic synthesis, photochemistry, materials science, environmental chemistry, green chemistry, and renewable energy). Advancements in these areas fuel the rapid growth of catalysis science. This book allows readers to reach a high-level of understanding in catalysis by learning from the perspectives of active practitioners. Unlike a textbook that provides a systematic, comprehensive, and historical education on the general topics of catalysis, this book offers critical case studies on select topics. Substantial emphasis is placed on the structural and fundamental properties that dictate catalyst performance, enabling readers to quickly understand and apply knowledge from cutting-edge studies and applications detailed within. This book can be utilized as a handbook, a textbook or textbook supplement, or a reference to guide future work"--
Download or read book Dithiolene Chemistry written by Edward I. Stiefel and published by John Wiley & Sons. This book was released on 2004-01-16 with total page 752 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Progress in Inorganic Chemistry series provides inorganic chemistry with a forum for critical, authoritative evaluations of advances in every area of the discipline. Volume 52, Dithiolene Chemistry: Synthesis, Properties, and Applications continues this forum with a focus on dithiolene chemistry and a significant, up-to-date selection of papers by internationally recognized researchers. Dithiolene complexes have a remarkable set of properties, a fact which has made them the object of intense study for new materials and sensors.
Download or read book Beauty in Chemistry written by Luigi Fabbrizzi and published by Springer Science & Business Media. This book was released on 2012-02-22 with total page 180 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Beauty of Chemistry in the Words of Writers and in the Hands of Scientists, by Margherita Venturi, Enrico Marchi und Vincenzo Balzani Living in a Cage Is a Restricted Privilege, by Luigi Fabbrizzi Inner and Outer Beauty, by Kenneth N. Raymond und Casey J. Brown The Mechanical Bond: A Work of Art, by Carson J. Bruns und J. Fraser Stoddart The Beauty of Knots at the Molecular Level, by Jean-Pierre Sauvage und David B. Amabilino
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 Vanadium Catalysis written by Manas Sutradhar and published by Royal Society of Chemistry. This book was released on 2020-11-05 with total page 526 pages. Available in PDF, EPUB and Kindle. Book excerpt: Vanadium is one of the more abundant elements in the Earth’s crust and exhibits a wide range of oxidation states in its compounds making it potentially a more sustainable and more economical choice as a catalyst than the noble metals. A wide variety of reactions have been found to be catalysed by homogeneous, supported and heterogeneous vanadium complexes and the number of applications is growing fast. Bringing together the research on the catalytic uses of this element into one essential resource, including theoretical perspectives on proposed mechanisms for vanadium catalysis and an overview of its relevance in biological processes, this book is a useful reference for industrial and academic chemists alike.
Download or read book Redox Active Ligands written by Marine Desage-El Murr and published by John Wiley & Sons. This book was released on 2024-01-31 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 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 Immobilized Catalysts written by Andreas Kirschning and published by Springer Science & Business Media. This book was released on 2004-11-22 with total page 354 pages. Available in PDF, EPUB and Kindle. Book excerpt: R. Haag, S. Roller: Polymeric Supports for the Immobilisation of Catalysts .- J. Horn, F. Michalek, C.C. Tzschucke, W. Bannwarth: Non-Covalently Solid-Phase Bound Catalysts for Organic Synthesis .- Y. Uozumi: Recent Progress in Polymeric Palladium Catalysts for Organic Synthesis .- D.E. Bergbreiter, J. Li: Applications of Catalysts on Soluble Supports .- B. Desai, C.O. Kappe: Microwave-Assisted Synthesis Involving Immobilized Catalysts .- A. Kirschning, G. Jas: Applications of Immobilized Catalysts in Continuous Flow Processes .- N. End, K.-U. Schöning: Immobilized Catalysts in Industrial Research and Application .- N. End, K.-U. Schöning: Immobilized Biocatalysts in Industrial Research and Production
Download or read book Nomenclature of Inorganic Chemistry written by International Union of Pure and Applied Chemistry and published by Royal Society of Chemistry. This book was released on 2005 with total page 379 pages. Available in PDF, EPUB and Kindle. Book excerpt: The 'Red Book' is the definitive guide for scientists requiring internationally approved inorganic nomenclature in a legal or regulatory environment.
Download or read book Inorganometallic Chemistry written by Thomas P. Fehlner and published by Springer Science & Business Media. This book was released on 2013-11-22 with total page 409 pages. Available in PDF, EPUB and Kindle. Book excerpt: There is a certain fascination associated with words. The manipulation of strings of symbols according to mutually accepted rules allows a language to express history as well as to formulate challenges for the future. But language changes as old words are used in a new context and new words are created to describe changing situations. How many words has the computer revolution alone added to languages? "Inorganometallic" is a word you probably have never encountered before. It is one created from old words to express a new presence. A strange sounding word, it is also a term fraught with internal contradiction caused by the accepted meanings of its constituent parts. "In organic" is the name of a discipline of chemistry while "metallic" refers to a set of elements constituting a subsection of that discipline. Why then this Carrollian approach to entitling a set of serious academic papers? Organic, the acknowledged doyenne of chemistry, is distinguished from her brother, inorganic, by the prefix "in," i. e. , he gets everything not organic. Organometallic refers to compounds with carbon-metal bonds. It is simple! Inorganometallic is everything else, i. e. , compounds with noncarbon-metal element bonds. But why a new term? Is not inorganic sufficient? By virtue of training, limited time, resources, co-workers, and so on, chemists tend to work on a specific element class, on a particular compound type, or in a particular phase. Thus, one finds element-oriented chemists (e. g.
Download or read book Hydrogen Transfer Reactions written by Gabriela Guillena and published by Springer. This book was released on 2016-09-27 with total page 393 pages. Available in PDF, EPUB and Kindle. Book excerpt: The series Topics in Current Chemistry Collections presents critical reviews from the journal Topics in Current Chemistry organized in topical volumes. The scope of coverage is all areas of chemical science including the interfaces with related disciplines such as biology, medicine and materials science. The goal of each thematic volume is to give the non-specialist reader, whether in academia or industry, a comprehensive insight into an area where new research is emerging which is of interest to a larger scientific audience. Each review within the volume critically surveys one aspect of that topic and places it within the context of the volume as a whole. The most significant developments of the last 5 to 10 years are presented using selected examples to illustrate the principles discussed. The coverage is not intended to be an exhaustive summary of the field or include large quantities of data, but should rather be conceptual, concentrating on the methodological thinking that will allow the non-specialist reader to understand the information presented. Contributions also offer an outlook on potential future developments in the field.
Download or read book Electron Spin Echo Envelope Modulation ESEEM Spectroscopy written by Sergei A. Dikanov and published by CRC Press. This book was released on 1992-07-27 with total page 432 pages. Available in PDF, EPUB and Kindle. Book excerpt: The first volume devoted entirely to Electron Spin Echo Envelope Modulation (ESEEM) Spectroscopy This valuable book provides an introduction and broad survey of topics in ESEEM spectroscopy, including the theory, instrumentation, peculiarities of ESE experiments, and analysis of experimental data with particular emphasis on orientationally disordered systems. Applications of ESEEM spectroscopy to study chemically and biologically important paramagnetic centers in single crystals, amorphous solids, and powders are discussed as well. Electron Spin Echo Envelope Modulation (ESEEM) Spectroscopy will benefit specialists in magnetic resonance spectroscopy, physicists, chemists, and biologists who use magnetic resonance in their research.
Download or read book Computational Molecular Spectroscopy written by Per Jensen and published by John Wiley & Sons. This book was released on 2000-11-02 with total page 696 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book describes the use of modern computational methods in predicting high resolution molecular spectra, which allows the experimental spectroscopist to interpret and assign real spectra. * Offers a comprehensive treatment of modern computation techniques. * Provides a collection of material from different areas of theoretical chemistry and physics. * Bridges the gap between traditional quantum chemistry and experimental molecular spectroscopy.
Download or read book Electronic Absorption Spectroscopy and Related Techniques written by D. N. Sathyanarayana and published by Universities Press. This book was released on 2001 with total page 556 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides a conceptual and experimental basis for the interpretation of electronic absorption spectroscopy and related techniques. The basic theories, instrumentation and interpretation of the spectra of organic and coordination compounds for structural studies are presented step-by-step, in an easily understandable style. related topics of emission spectroscopes are covered as well.
