Download or read book Spectroscopic Studies of Chromium III Complexes written by Whiting Newton Shepard and published by . This book was released on 1970 with total page 226 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Synthesis and Spectroscopic Studies of Chromium III Amino Acid Complexes written by Ahmad Rostam-Kolayi and published by . This book was released on 1974 with total page 98 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Synthesis and Structural Studies of N and P donor Ligands in Chromium III Complexes written by Nicholas Frederick Brennan and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The fundamental knowledge of Cr(III) chemistry has been enhanced via detailed structural and spectroscopic studies of largely novel compounds that may potentially be active tri- and tetramerisation precursors. The compounds are based on various monodentate and bidentate nitrogen and phosphorus ligands which have been coordinated to [CrCl3 (thf) 3]. The few compounds that have been synthesised previously have in this study been made via novel synthetic routes and incorporate a combination of new and more detailed analysis than was carried out previously. The eight structures determined, in addition to offering novel crystallographic data, also provided insights into the synthetic pathways leading to compound formation. The isolation of monomeric structures suggests direct ligand substitution, while the cationic-anionic structures suggest the presence of dimeric intermediates which have been cleaved asymmetrically. Infrared and Raman spectra of these structures were able to add weight to these pathway proposals and, by means of vibrational comparisons, assisted in the general band assignments of the compounds' spectra where structures were not available. Vibrational shifts relative to the free ligands, as well as metal ligand vibrations in the far infrared region, were also of significant value in terms of ligand coordination and geometry. Closely associated with the infrared and Raman spectra analysis was the generation of theoretical spectra using Density Functional Theory calculations. The excellent agreement between the calculated and experimental spectra confirmed the vibrational assignments. Also generated by computational means were the highest occupied and lowest unoccupied molecular orbitals (HOMO and LUMO) of the compounds which indicated the sites of potential nucleophilic and electrophilic attack. 1H NMR spectroscopy is a technique normally avoided when studying paramagnetic materials. However, by employing a largely novel approach, information pertaining to both ligand coordination and reaction times was obtained. FAB-MS assisted in the confirmation that the single crystal determinations did indeed reflect the composition of the bulk precipitated samples. It also provided additional structural information through the identification of fragmentation patterns which could not be gained by techniques such as elemental analysis.
Download or read book Phosphorus The Carbon Copy written by Keith B. Dillon and published by John Wiley & Sons. This book was released on 1998-03-06 with total page 704 pages. Available in PDF, EPUB and Kindle. Book excerpt: Phosphorus: The Carbon Copy examines the extraordinary similarity between low coordinate phosphorus compounds and unsaturated carbon compounds. Written by three of the leading researchers in the field of modern phosphorus chemistry, Phosphorus: The Carbon Copy focuses on the interface between phosphorus and the transition metal elements and deals with the most recent aspects of unsaturated organophosphorus compounds and their coordination chemistry. Aimed at graduate students as well as academic and industrial researchers, this concise volume publicisies the extraordinary potential of these new phosphorus compounds for applications in catalysis, molecular materials and biochemistry.
Download or read book The Polarographic and Spectroscopic Studies of Cis and Trans Coordination Compounds of Chromium III Rhodium III and Cobalt III written by Ting-Tung Lea and published by . This book was released on 1975 with total page 96 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Spectroscopic Properties of Superexchange coupled Binuclear Chromium III Complexes written by Li Chen and published by . This book was released on 1988 with total page 300 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Spectra of Chromium iii Complexes written by Leslie S. Forster and published by . This book was released on 1967 with total page 65 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Nutritional Biochemistry of Chromium III written by John Vincent and published by Elsevier. This book was released on 2018-09-18 with total page 400 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Nutritional Biochemistry of Chromium(III), Second Edition, reviews the fields of chromium biochemistry and nutrition and how they have dramatically changed in the last decade. Editor John Vincent has lead much of the research that has resulted in new discoveries and reversals of previously held beliefs, such as health concerns surrounding the toxicity of chromium(III). New sections include a review of new evidence showing why chromium may not be an essential element, why national recommendations may need updating, and new data on the use of chromium supplementation in animal feeds. Discussions on the controversial topic of the role of chromium(III) at the molecular level in insulin signaling and information on cell cultures and in vitro assays of chromium toxicity are also covered. Examines all of the significant research surrounding chromium, providing discussion on both sides of controversial issues Features new evidence that shows why chromium may not be an essential element Details why national recommendations may need updating Edited by leading expert in the field of chromium, with new contributions from leaders in different aspects of chromium research
Download or read book The Bioinorganic Chemistry of Chromium written by John B. Vincent and published by John Wiley & Sons. This book was released on 2012-10-04 with total page 259 pages. Available in PDF, EPUB and Kindle. Book excerpt: Chromium exists in nature as complexes of two stable oxidation states – trivalent chromium(III) and hexavalent chromium(VI). Although trivalent chromium is required in trace amounts for sugar and lipid metabolism in humans and its deficiency may cause a disease called chromium deficiency; hexavalent chromium is toxic and carcinogenic. As chromium compounds were used in dyes and paints and the tanning of leather, these compounds are often found in soil and groundwater at abandoned industrial sites, now needing environmental cleanup and remediation. The Bioinorganic Chemistry of Chromium: From Biochemistry to Environmental Toxicology takes a critical look at what the biochemical data indicate about chromium's role in the body and the biological mechanisms of its toxicology. Topics covered include: What do we know about the biochemical roles and mechanisms of chromium? Is chromium an essential element in the mammalian diet? Is chromium(III) effective as a nutraceutical, a therapeutic agent, and as a supplement in animal feed? What is the biochemistry behind the toxicology of chromium(III) and chromium(VI):the mechanisms of metabolism, genetic and epigenetic effects, and disruption of cell signalling? What are the current chromium(VI) policies and positions from regulatory agencies? The Bioinorganic Chemistry of Chromium: From Biochemistry to Environmental Toxicology is an important contribution to the bioinorganic and trace element biochemical fields which will find a place on the bookshelves of bioinorganic chemists, biochemists, inorganic chemists, toxicologists, nutritionists and regulatory affairs professionals.
Download or read book The Electronic Spectra and Electronic Energy Levels of Tetragonal Chromium III Complexes written by Bohdan Hindulak Schatschneider and published by . This book was released on 2001 with total page 126 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Study of Some Chromium III Coordination Complexes by Luminescence Spectroscopy written by D. J. D. Palacio and published by . This book was released on 1978 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Some Kinetic Studies of Chromium III Complexes written by Robert Le Johnson and published by . This book was released on 1958 with total page 220 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book High Resolution EPR written by Graeme Hanson and published by Springer Science & Business Media. This book was released on 2009-06-19 with total page 666 pages. Available in PDF, EPUB and Kindle. Book excerpt: Metalloproteins comprise approximately 30% of all known proteins, and are involved in a variety of biologically important processes, including oxygen transport, biosynthesis, electron transfer, biodegradation, drug metabolism, proteolysis, and hydrolysis of amides and esters, environmental sulfur and nitrogen cycles, and disease mechanisms. EPR spectroscopy has an important role in not only the geometric structural characterization of the redox cofactors in metalloproteins but also their electronic structure, as this is crucial for their reactivity. The advent of x-ray crystallographic snapshots of the active site redox cofactors in metalloenzymes in conjunction with high-resolution EPR spectroscopy has provided detailed structural insights into their catalytic mechanisms. This volume was conceived in 2005 at the Rocky Mountain Conference on Analytical Chemistry (EPR Symposium) to highlight the importance of high-resolution EPR spectroscopy to the structural (geometric and electronic) characterization of redox active cofactors in metalloproteins. We have been fortunate to have enlisted internationally recognized experts in this joint venture to provide the scientific community with an overview of high-resolution EPR and its application to metals in biology. This volume, High-Resolution EPR: Applications to Metalloenzymes and Metals in Medicine, covers high-resolution EPR methods, iron proteins, nickel and copper enzymes, and metals in medicine. An eloquent synopsis of each chapter is provided by John Pilbrow in the Introduction. A second volume, Metals in Biology: Applications of High-Resolution EPR to Metalloenzymes, will appear later this year covering the complement of other metalloproteins. One of the pioneers in the development of pulsed EPR and its application to metalloproteins was Arthur Schweiger, whose contribution we include in this volume. Unfortunately, he passed away suddenly during the preparation of this volume. The editors and coauthors are extremely honored to dedicate this volume to the memory of Arthur Schweiger in recognition of his technical advances and insights into pulsed EPR and its application to metalloproteins. Arthur was extremely humble and treated everyone with equal respect. He was a gifted educator with an ability to explain complex phenomena in terms of simple intuitive pictures, had a delightful personality, and continues to be sadly missed by the community. It is an honor for the editors to facilitate the dissemination of these excellent contributions to the scientific community. Suggestions for future volumes are always appreciated.
Download or read book Thermal Studies of Chromium III Complexes written by Chen Ling Liong and published by . This book was released on 1999 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Electronic Structure and Excited State Dynamics of Chromium III Complexes written by Joel Nicholas Schrauben and published by . This book was released on 2010 with total page 734 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Optical Spectra and Chemical Bonding in Transition Metal Complexes written by Thomas Schönherr and published by Springer Science & Business Media. This book was released on 2004-09-30 with total page 332 pages. Available in PDF, EPUB and Kindle. Book excerpt: With contributions by numerous experts
Download or read book Polarized Crystal Spectra of Quadrate Chromium III Complexes written by Robert L. Klein (Jr.) and published by . This book was released on 1971 with total page 67 pages. Available in PDF, EPUB and Kindle. Book excerpt: The polarized crystal spectra of a series of tetragonal trans- diacidobis (ethylenediamine) chromium (III) complexes, trans-[Cr(en)2XY], where X= Y = Br-, H2O, F-, Cl- and X= H2O, Y = OH-, F-, have been measured at liquid nitrogen temperature, achieving better resolution of the split components of the cubic spin-allowed bands, and also definite energy level assignments. The observed band positions have been fitted with the predicted transition energies by the use of the appropriate energy equations for d^3 configuration immersed in tetragonal fields with full configuration interaction. The ligand field parameters, which include the cubic and axial, and the electron correlation parameter B have been evaluated by such a fitting. The derived parameters have been analyzed and their significance discussed. Using thick crystals, we have uncovered a rich doublet structure in some of the complexes and tentative values of the electron correlation parameter C have been obtained for all the complexes.
