Download or read book Platinum Ligand Pi Bonding Interactions written by Yuen-Chi Law and published by . This book was released on 2017-01-27 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation, "Platinum-ligand PI Bonding Interactions: the Ligand-to-ligand Charge Transfer Transitions and Supramolecular Chemistry of Platinum(II) Acetylide and Thiolate Complexes" by Yuen-chi, Law, 羅婉芝, was obtained from The University of Hong Kong (Pokfulam, Hong Kong) and is being sold pursuant to Creative Commons: Attribution 3.0 Hong Kong License. The content of this dissertation has not been altered in any way. We have altered the formatting in order to facilitate the ease of printing and reading of the dissertation. All rights not granted by the above license are retained by the author. Abstract: Abstract of thesis entitled PLATINUM-LIGAND PI BONDING INTERACTIONS: THE LIGAND-TO-LIGAND CHARGE TRANSFER TRANSITIONS AND SUPRAMOLECULAR CHEMISTRY OF PLATINUM(II) ACETYLIDE AND THIOLATE COMPLEXES Submitted by Law Yuen Chi for the degree of Doctor of Philosophy at The University of Hong Kong in November 2006 Platinum(II) complexes have attracted considerable interest for decades, namely due to their luminescent properties and molecular aggregations. A wide emission spectral range and the enhancement of emission properties, such as quantum yields and emission lifetimes, can be achieved by choosing suitable substituents on ligands of platinum(II) complexes. The aggregation and deaggregation alter the photophysical and/or physical properties of platinum(II) chemistry. The syntheses, characterization, spectroscopic, and photophysical properties of platinum(II) acetylide and thiolate complexes are described, and four systems examined in detail. Tuning of the spectroscopic and photophysical properties of terpyridyl platinum(II) complexes bearing alkynyl auxiliaries, namely [Pt(N DEGREESN DEGREESN)C≡C(C H C≡C) R] [(N DEGREESN DEGREESN) = 6 4 n-1 4,4′,4′′-trichloro-2,2′ 6′,2′′-terpyridine or 4,4′,4′′-tri-tert-butyl-2,2′ 6′,2″-terpyridine ( Bu tpy); n = 1-3; R = aryl or alkyl] by varying the acetylide chain length and substituents on the terpyridine and acetylide ligands, is presented. The effects of acetylide chain length n of X = H and N(CH ) of 3 2 t + [Pt( Bu tpy)C≡C(C H C≡C) C H -X-4] [n = 1-3] on the absorption energies are 3 6 4 n-1 6 4 varied due to different electron delocalization in the coordinated arylacetylide. t + n Resonance Raman spectra of [Pt( Bu tpy)(C≡CR)] (R = Bu, Ph, or C H -OCH -4) 3 6 4 3 revealed that the low-energy absorption bands are derived from two different transition states. The triplet emissive-states of the alkylacetylide complexes are assigned to an admixture of [d (Pt) → π*(tpy)] metal-to-ligand charge transfer 3 3 3 ( MLCT) and [π(C≡C) → π*(tpy)] ligand-to-ligand charge transfer ( LLCT) 3 transitions, whereas those of the arylacetylide complexes are ascribed to [π(C≡CAr) → π*(tpy)] ( LLCT) transition. A phosphorescent binuclear terpyridyl platinum(II) complex with the bridging ligand 2,5-bis-(4-ethynylphenyl)-[1,3,4]oxadiazole gelates in various solvents. Based on powder X-ray diffraction, small angle X-ray scattering, UV-vis absorption, emission, variable temperature H NMR measurements, and the X-ray crystal structure of monomeric terpyridyl platinum(II) complex of 2,5-diaryl-[1,3,4]oxadiazole, the driving force for the gelation is proposed to be intermolecular π-π interactions between [( Bu tpy)PtC≡C] moieties in staggered fashion, even though the role of electrostatic, dipole-dipole, and van der Waals interactions could not be excluded. Oligomeric complexes of [Pt(tpy)] moieties tethered by C≡C were found to have interesting thermal behavior as observed by variable temperature H NMR spectroscopy. This thermal behavior is attributed to molecular interactions, such as intermolecular Pt---Pt and π-π interactions. The extent of molecular interactions could be controlled by varying the substituent on acetylide ligand. The absorp

Download or read book The Nature of the Ligand metal Bonding in Platinum II Complexes where One Or More of the Ligands Has a Pi system written by Nelson Flagge Phelan and published by . This book was released on 1970 with total page 392 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Small Molecule Binding to Electrophilic Trigonal Pyramidal Platinum Palladium and Nickel written by Charlene Tsay and published by . This book was released on 2013 with total page 266 pages. Available in PDF, EPUB and Kindle. Book excerpt: Chapter 1 A general introduction to the concepts and background of several types of transition metal complexes that motivate and inform the research described herein. These include a-complexes and molecular adducts of dinitrogen, dihydrogen, and carbon dioxide. Chapter 2 Trigonal bipyramidal platinum(II) complexes of the monoanionic, tetradentate, triphosphine [SiPR3 ([SiP3R]- = [(2-R2PC6H4)3Si]-; R = Ph, iPr) ligand are prepared and shown to provide access to cationic species with divergent behavior. The less electron-rich phenyl-substituted ligand renders the platinum center extremely electrophilic, leading to structurally characterized examples of weakly-donating ligands bound in the fifth, apical coordination site. Of particular interest is the structure of the toluene adduct, which suggests a possible interaction between the platinum center and an aryl C-H bond. When the ligand phosphines are instead substituted by the more electron-rich isopropyl groups, the electrophilicity of the cationic platinum is shown to be mitigated, allowing access to a four-coordinate, trigonal pyramidal platinum center. The crystallographically characterized geometry for this divalent platinum is in contrast to the canonical square planar configuration for d8, 16-electron transition metal complexes. The palladium analogue is also synthesized and shown to possess the same coordination. Chapter 3 Cationic nickel complexes of the [SiPR3] ligand are synthesized and, in contrast to their platinum and palladium congeners, facilitate the surprising binding of molecular dinitrogen to electrophilic nickel(II) centers. The extremely high stretching frequencies of these bound N2 moieties attest to their minimal activation, and the stability of these complexes is shown to arise from increased adonation from the N2 to the cationic nickel center, which compensates for the relative lack of it back-bonding that stabilizes N2 adducts in less electrophilic systems. These cationic nickel species are additionally shown to form thermally stable adducts of molecular dihydrogen. The relative binding strengths of N2 and H2 to these nickel centers are explored and shown to be modulated by the ligand phosphine substituents. Furthermore, evidence of linear binding of carbon dioxide is presented, representing an electrophilic approach to carbon dioxide activation that is in contrast to the low-valent, nucleophilic metal paradigm. Chapter 4 The four-coordinate neutral nickel boratrane (TPiPrB = (2-iPr2PC6H4)3B) reported in the literature represents an isostructural counterpart to the cationic {[SiiPr3]Ni}+ species presented in Chapter 3. Though these two compounds are formally separated by two oxidation states of nickel, the Lewis-acidic nature of the Z-type borane ligand in (TP'PrB)Ni renders it valence-isoelectronic with {[SiiPr3]Ni}+. The reactivity toward N2 and H2 of (TPiPr'B)Ni, as well as that of the new compound (TPPhB)Ni, is explored and discussed in context of what is observed for the {[SiPR3]Ni}+ system. The neutral (TPiPr'B)Ni, while presumably a better [pi] back-bonder than cationic {I[SiPip' 3]Ni}T, is demonstrated not to bind N2, though a very weak, fluxional interaction with H2 at low temperature is hypothesized. The more electrophilic (TP PhB)Ni exhibits room temperature interactions with both N2 and H2, though the nature of these interactions has yet to be confirmed. These results thus underline the importance of [sigma]-donation in stabilizing N2 and H2 adducts of poorly 7r back-bonding metal centers. Chapter 5 Cobalt(I) complexes of [SiPR3] provide an additional isostructural, isoelectronic point of comparison to the cationic nickel species presented in Chapter 3. The dinitrogen adducts [SiP'i' 3]Co(N2) and [SiPPh3]Co(N2), previously reported from our laboratory, feature strongly bound N2 ligands that are not labile to vacuum. The corresponding dihydrogen adducts are generated slowly under an H2 atmosphere. The intact nature of both dihydrogen ligands, which also are not labile to vacuum, is reflected in their NMR spectroscopic parameters. The thermal stability of these compounds enabled crystallization of [SiPi'' 3]Co(H2) which, along with the related (TP'i'B)Co(H2) complex also developed in our laboratory, represent the first structurally characterized dihydrogen adducts of cobalt. Additional comparisons are made between the relative N2 and H2 binding strengths of this system and those of the structurally and electronically related family of [SiPR3] and (TpRB) metal complexes. Appendix A The asymmetric dinucleating ligand [NOPPh], designed to contain both a hard, N-donor binding site and a soft-P-donor binding site, is synthesized and shown to form a diiron complex that features asymmetric bonding to the bridging acetates. The corresponding symmetric, allphosphine dinucleating ligand [POPPh], proves to be more conducive to further study, and provides access to the symmetric diiron, di-([mu]-bromide) starting material {[POPPh ]Fe 2Br2} {BArF4 }. Addition of hydrazine generates the asymmetric, unbridged N2H4 adduct, which features localized diamagnetic and paramagnetic iron centers. The conformation of this species additionally demonstrates the flexibility of this ligand framework. Reduction of the diiron(II) starting material in the presence of PMe3 results in formation of a putative asymmetric iron(O)/iron(I) dimetallic complex, in which an N2 molecule is bound to the diamagnetic iron center, while the PMe3 is ligated to the high-spin iron center and rendered NMR silent. The N2 ligand is shown to be reversibly displaced by H2 , suggesting the formation of a dihydrogen adduct, as well as by CO2, which is postulated to bind as a bent, [eta]2(C,O) ligand.

Download or read book Metal Ligand Interactions From Atoms to Clusters to Surfaces written by Dennis R. Salahub and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 428 pages. Available in PDF, EPUB and Kindle. Book excerpt: Metal-ligand interactions are currently being studied in different fields, from a variety of points of view, and recent progress has been substantial. Whole new classes of compounds and reactions have been found; an arsenal of physical methods has been developed; mechanistic detail can be ascertained to an increasingly minute degree; and the theory is being developed to handle systems of ever-growing complexity. As usual, such multidisciplinarity leads to great opportunities, coupled with great problems of communication between specialists. It is in its promotion of interactions across these fields that Metal-Ligand Interactions: From Atoms, to Clusters, to Surfaces makes its timely contribution: the tools, both theoretical and experimental, are highly developed, and fundamental questions remain unanswered. The most fundamental of these concerns the nature of the microscopic interactions between metal atoms (clusters, surfaces) and ligands (atoms, molecules, absorbates, reagents, products) and the changes in these interactions during physical and chemical transformation. In Metal-Ligand Interactions, leading experts discuss the following, vital aspects: ab initio theory, semi-empirical theory, density functional theory, complexes and clusters, surfaces, and catalysis.

Download or read book Metal Catalyzed Polymerization written by Samir Chikkali and published by CRC Press. This book was released on 2017-08-03 with total page 227 pages. Available in PDF, EPUB and Kindle. Book excerpt: The proposed book focusses on metal mediated/catalyzed “controlled/living radical polymerization” (CRP/LRP) methods. It surveys a wide variety of catalyzed polymerization reactions, making it essentially a “one stop” review in the field. A significant contribution to polymer science is “metathesis polymerization” discovered by Grubbs and others. The book will cover various metathesis polymerization methods and implications in polymer industry.

Download or read book Organometallic and Coordination Chemistry of Platinum written by Umberto Belluco and published by . This book was released on 1974 with total page 728 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Organo Transition Metal Compounds and Related Aspects of Homogeneous Catalysis written by B. L. Shaw and published by Elsevier. This book was released on 2016-06-06 with total page 231 pages. Available in PDF, EPUB and Kindle. Book excerpt: Organo-Transition Metal Compounds and Related Aspects of Homogeneous Catalysis covers compounds that possess carbon atoms bonded to metal and to other carbon atoms. The order in which the substances appear in the book is based on the number of carbon atoms it have. The first section is about the alkyl, aryl, ethynyl, acyl, and carbene complexes. The second section deals with olefin and chelating diolefin complexes and complexes formed from acetylene. The following section covers the p-allylic complexes. The structures, stability, and bonding of alkyl and aryl complexes are fully covered. The magnetic moments and electronic spectra are discussed in detail.The fourth section discusses the conjugated diolefinic complexes that contain butadiene or cyclobutadiene. The rest of the book focuses on cyclopentadienyls, arene complexes, tropylium complexes, and complexes formed from cyclo-octatetraene or azulene. The book will be a useful tool for chemists, chemical engineers, and students and researchers in the field of chemistry.

Download or read book Introduction to Metal Complex Chemistry written by M. Tsutsui and published by Springer Science & Business Media. This book was released on 2013-06-29 with total page 220 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Plenum Press series, Monographs in Inorganic Chemistry, is intended to fill an obvious need for high-level surveys of recent research in that area, particularly in matters which go beyond the traditional or classical bound aries of the subject. The study of n-bonding of hydrocarbon groups (and their derivatives) to metals is exactly that kind of subject, for it provides a new way of understanding the behavior of metals (which constitute four-fifths of all the chemical elements). In addition, n-bonding has expanded the intriguing area of organometallic chemistry threefold, bringing in all the transition metals, the lanthanides, and the actinides. So much has been discovered and developed in the area of n-bonded "complexes" of the metals that important new industrial processes based on such substances have been developed. A truly comprehensive review of all n-bonded compounds of the metals would now result in an impossibly large and expensive volume, and would require monthly revision. Instead, the present authors have wisely decided to write a survey which outlines the general aspects of preparation, properties, structure, reactions, and uses of such compounds-a survey which can serve as a textbook, but which can also lead the more experienced practitioner to the most advanced literature on the subject. They have clarified and condensed the subject by means of good organization and a liberal use of diagrams-features which will please the general reader.

Download or read book Techniques in Inorganic Chemistry written by Jr., John P. Fackler and published by CRC Press. This book was released on 2010-07-16 with total page 219 pages. Available in PDF, EPUB and Kindle. Book excerpt: Inorganic chemistry continues to generate much current interest due to its array of applications, ranging from materials to biology and medicine. Techniques in Inorganic Chemistry assembles a collection of articles from international experts who describe modern methods used by research students and chemists for studying the properties and structure

Download or read book Supramolecular Coordination Complexes written by Sankarasekaran Shanmugaraju and published by Elsevier. This book was released on 2022-10-28 with total page 498 pages. Available in PDF, EPUB and Kindle. Book excerpt: Supramolecular Coordination Complexes: Design, Synthesis, and Applications discusses the growth of the field and explores the advantages, opportunities and latest applications of supramolecular complexes. Beginning with an introduction to design principles, synthetic methods, and post-synthetic functionalization of supramolecular complexes, the book goes on to compile the different analytical and computational modeling methods used to understand the structure and functional properties of supramolecular structures. Applications of supramolecular complexes in biomedicine, sensing, catalysis and materials are then explored in detail. Drawing on the knowledge of a global team of experts, this book provides a wealth of interesting information for students and researchers working in the design, synthesis or application of such complexes. Discusses cutting-edge approaches for the investigation of supramolecular coordination chemistry Summarizes a varied range of supramolecular coordination, complex designs and applications Highlights the interdisciplinary connections between supramolecular chemistry and the fields of biology and materials science

Download or read book The Organometallic Chemistry of the Transition Metals written by Robert H. Crabtree and published by John Wiley & Sons. This book was released on 2005-06-14 with total page 600 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fully updated and expanded to reflect recent advances, this Fourth Edition of the classic text provides students and professional chemists with an excellent introduction to the principles and general properties of organometallic compounds, as well as including practical information on reaction mechanisms and detailed descriptions of contemporary applications.

Download or read book Non covalent Interactions in the Synthesis and Design of New Compounds written by Abel M. Maharramov and published by John Wiley & Sons. This book was released on 2016-05-03 with total page 481 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book aims to overview the role of non-covalent interactions, such as hydrogen and halogen bonding, π-π, π-anion and electrostatic interactions, hydrophobic effects and van der Waals forces in the synthesis of organic and inorganic compounds, as well as in design of new crystals and function materials. The proposed book should allow to combine, in a systematic way, recent advances on the application of non-covalent interactions in synthesis and design of new compounds and functional materials with significance in Inorganic, Organic, Coordination, Organometallic, Pharmaceutical, Biological and Material Chemistries. Therefore, it should present a multi- and interdisciplinary character assuring a rather broad scope. We believe it will be of interest to a wide range of academic and research staff concerning the synthesis of new compounds, catalysis and materials. Each chapter will be written by authors who are well known experts in their respective fields.

Download or read book Current Trends in X Ray Crystallography written by Annamalai Chandrasekaran and published by BoD – Books on Demand. This book was released on 2011-12-16 with total page 452 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book on X-ray Crystallography is a compilation of current trends in the use of X-ray crystallography and related structural determination methods in various fields. The methods covered here include single crystal small-molecule X-ray crystallography, macromolecular (protein) single crystal X-ray crystallography, and scattering and spectroscopic complimentary methods. The fields range from simple organic compounds, metal complexes to proteins, and also cover the meta-analyses of the database for weak interactions.

Download or read book Metal Interactions with Boron Clusters written by Russell N. Grimes and published by Springer Science & Business Media. This book was released on 2013-11-11 with total page 335 pages. Available in PDF, EPUB and Kindle. Book excerpt: Molecular clusters, in the broad sense that the term is commonly understood, today comprise an enormous class of species extending into virtually every important area of chemistry: "naked" metal clusters, transition metal carbonyl clusters, hydrocarbon cages such as cubane (C H ) and dodecahedrane (C H ), 8 8 20 20 organometallic cluster complexes, enzymes containing Fe S or MoFe S 4 4 3 4 cores, high polymers based on carborane units, and, of course, the many kinds of polyhedral borane species. So large is the area spanned by these diverse classes that any attempt to deal with them comprehensively in one volume would, to say the least, be ambitious-and also premature. We are presently at a stage where intriguing relationships between the various cluster families are becoming apparent (particularly in terms of bonding descriptions), and despite large dif ferences in their chemistry an underlying unity is gradually developing in the field. For example, structural changes occurring in Fe S cores as electrons are 4 4 pumped in and out, in some measure resemble those observed in boranes and carboranes. The cleavage of alkynes via incorporation into carborane cages and subsequent cage rearrangement, a sequence familiar to boron chemists, is a thermodynamically favored process which may be related to the behavior of unsaturated hydrocarbons on metal surfaces; analogies of this sort have drawn attention from theorists and experimentalists.

Download or read book Encyclopedia of Spectroscopy and Spectrometry written by and published by Academic Press. This book was released on 2010-04-09 with total page 7207 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Second Edition of the Encyclopedia of Spectroscopy and Spectrometry pulls key information into a single source for quick access to answers and/or in-depth examination of topics. "SPEC-2" covers theory, methods, and applications for researchers, students, and professionals—combining proven techniques and new insights for comprehensive coverage of the field. The content is available in print and online via ScienceDirect, the latter of which offers optimal flexibility, accessibility, and usability through anytime, anywhere access for multiple users and superior search functionality. No other work gives analytical and physical (bio)chemists such unprecedented access to the literature. With 30% new content, SPEC-2 maintains the "authoritative, balanced coverage" of the original work while also breaking new ground in spectroscopic research. Incorporates more than 150 color figures, 5,000 references, and 300 articles (30% of which are new), for a thorough examination of the field Highlights new research and promotes innovation in applied areas ranging from food science and forensics to biomedicine and health Features a new co-editor: David Koppenaal of Pacific Northwest National Laboratory, Washington, USA, whose work in atomic mass spectrometry has been recognized internationally

Download or read book Catalysis written by James J Spivey and published by Royal Society of Chemistry. This book was released on 2007-10-31 with total page 482 pages. Available in PDF, EPUB and Kindle. Book excerpt: There is an increasing challenge for chemical industry and research institutions to find cost-efficient and environmentally sound methods of converting natural resources into fuels chemicals and energy. Catalysts are essential to these processes and the Catalysis Specialist Periodical Report series serves to highlight major developments in this area. This series provides systematic and detailed reviews of topics of interest to scientists and engineers in the catalysis field. The coverage includes all major areas of heterogeneous and homogeneous catalysis and also specific applications of catalysis such as NOx control kinetics and experimental techniques such as microcalorimetry. Each chapter is compiled by recognised experts within their specialist fields and provides a summary of the current literature. This series will be of interest to all those in academia and industry who need an up-to-date critical analysis and summary of catalysis research and applications. Catalysis will be of interest to anyone working in academia and industry that needs an up-to-date critical analysis and summary of catalysis research 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 Electrocatalysis on Non metallic Surfaces written by Alan D. Franklin and published by . This book was released on 1976 with total page 396 pages. Available in PDF, EPUB and Kindle. Book excerpt: