Download or read book Application of Electron Paramagnetic Resonance Spectroscopy to the Study of Surface Defects and Adsorbed Molecules written by Jack H. Lunsford and published by . This book was released on 1966 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Electron Paramagnetic Resonance Spectroscopy written by Patrick Bertrand and published by Springer. This book was released on 2021-02-04 with total page 433 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book shows how the fundamentals of electron paramagnetic resonance (EPR) spectroscopy are practically implemented and illustrates the diversity of current applications. The technique is used at various levels, and applications are presented in order of increasing difficulty, with reference to theoretically obtained results. This book features a diverse array of application examples, from fields such as ionizing radiation dosimetry, neurodegenerative diseases, structural transitions in proteins, and the origins of terrestrial life. The final chapter of this book highlights the principles and applications of the technique of ferromagnetic resonance spectroscopy, followed by a brief introduction to advanced EPR techniques such as electron spin echo envelope modulation (ESEEM), hyperfine sub-level correlation (HYSCORE), pulsed electron-electron double resonance (PELDOR), and continuous wave electron nuclear double resonance (ENDOR) experiments.
Download or read book Application of Electron Paramagnetic Resonance Spectroscopy to the Study of Surface Defects and Adsorbed Molecules written by Jack H. Lunsford and published by . This book was released on 1966 with total page 19 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Electron Paramagnetic Resonance written by Bruce C Gilbert and published by Royal Society of Chemistry. This book was released on 2012-11-30 with total page 323 pages. Available in PDF, EPUB and Kindle. Book excerpt: Specialist Periodical Reports provide systematic and critical review coverage in major areas of chemical research. Compiled by teams of leading authorities in the relevant subject, the series creates a unique service for the active research chemist with regular critical in-depth accounts of progress in particular areas of chemistry. Subject coverage of all volumes is very similar and publication is on an annual or biennial basis. As EPR continues to find new applications in virtually all areas of modern science, including physics, chemistry, biology and materials science, this series caters not only for experts in the field, but also those wishing to gain a general overview of EPR applications in a given area.
Download or read book Electron Paramagnetic Resonance Studies of Point Defects in AlGaN and SiC written by Xuan Thang Trinh and published by Linköping University Electronic Press. This book was released on 2015-05-12 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt: Point defects in semiconductor materials are known to have important influence on the performance of electronic devices. For defect control, knowledge on the model of defects and their properties is required. Information on defects, such as the symmetry and the localization of spins, is essential for identification of defects and understanding their electronic structure. Such information can be obtained from Electron Paramagnetic Resonance (EPR). In many cases, the energy levels of defects can be determined from photoexcitation EPR (photo-EPR) or temperature dependence of the EPR signal. The thesis contains six papers, focusing on the identification and electronic structure investigation of defects and impurities in AlxGa1-xN (x~0.7-1) and silicon carbide (SiC) using EPR in combination with other electrical characterizations and density functional theory calculations. The two first papers concern EPR studies of silicon (Si) in AlGaN alloys. Due to its direct and wide band gap which can be tailored from 3.4 eV for GaN to 6.2 eV for AlN, high-Al-content wurtzite AlxGa1-xN (x?0.7) has been considered as a promising material for fabrication of compact, high-efficiency and non-toxic deep ultraviolet light-emitting diodes (LEDs) and laser diodes (LDs) for replacing low-efficiency and toxic mercury lamps in water/air purification and sterilization. Si is commonly used for n-type doping in AlGaN and AlN, but the conductivity of Si-doped AlxGa1-xN was often reported to drop abruptly at high Al content (x>0.7) and the reason was often speculated to be due to either carrier compensation by other deep levels or Si itself when it transforms from a shallow donor to a DX (or negative-U) center which acts as an acceptor. In paper 1, we showed that Si already forms a stable DX center in AlxGa1-xN with x ~0.77. However, with the Fermi level locating only ~3 meV below the neutral charge state, Ed, Si still behaves as a shallow donor. Negligible carrier compensation by oxygen (O) in Al0.77Ga0.23N:Si layers was observed, suggesting that at such Al content, O does not seem to hinder the n-type doping in the material. In paper 2, we found the coexistence of two Si DX centers, the stable DX1 and the metastable DX2, in AlxGa1-xN for x?0.84. For the stable DX1 center, abrupt deepening of the energy level of the negative charge state DX–, EDX, which determines the ionization energy Ea of the Si donor, with increasing of the Al content for x?0.83 was observed. The dependence of Ea on the Al content in AlxGa1-xN:Si layers (0.79?x?1) was determined. The results explain the drastic decrease of the conductivity as often reported for AlxGa1-xN:Si in previous transport studies. For the metastable DX2 center, we found that the EDX level remains close to Ed for x=0.84÷1. SiC is a wide band-gap semiconductor having high-thermal conductivity, high breakdown field, and large saturated electron drift velocity which are essential properties for high-voltage and high-power devices. In paper 3, the identification of niobium (Nb) in 4Hand 6H-SiC grown by high-temperature chemical vapor deposition (CVD) by EPR and theoretical calculations is presented. We showed that the incorporated Nb formed asymmetric split-vacancy defect (NbSiVC) in which Nb locates in a divacancy, closer to the Si vacancy, and prefers only the hexagonal-hexagonal configuration. In papers 4 and 5, we present the identification and the electronic structure of the negative-U Z1/Z2 center in 4HSiC. The Z1/Z2 defect is known to be the most common deep level revealed by Deep Level Transient Spectroscopy (DLTS) in 4H-SiC epitaxial layers grown by CVD. The center is also known to be the lifetime killer in as-grown CVD material and, therefore, attracts much attention. Using high-doped n-type free-standing 4H-SiC layers irradiated with low-energy (250 keV) electrons, which mainly displace carbon atoms creating C vacancies (VC), C interstitials and their associated defects, it was possible to increase the irradiation dose and, hence, the defect concentration, allowing the application of EPR and DLTS on the same samples. In paper 4, using EPR, photo-EPR, DLTS and capacitance-voltage measurements, we showed that the Z1/Z2 center is related to the (2-|0) level of VC and its higher-lying levels Z1 and Z2 are related to the (-|0) levels of VC at the hexagonal (h) and quasi-cubic (k) sites, respectively. In paper 5, combining EPR and supercell calculations, the negatively charged VC at the k-site was identified. We obtained the excellent agreement in the energy levels of Z1/Z2 determined by DLTS and energy levels of VC calculated by supercell calculations and observed clear negative-U behaviors of the negatively charged VC at both k and h-sites by EPR measurements, consolidating our assignment of the Z1/Z2 levels to the negatively charged states of VC. In paper 6, we studied a defect related to displaced C atoms in n-type 4H-SiC irradiated by low-energy electrons. In irradiated layers, we observed an EPR center at room temperature. After annealing at temperatures in the range of 300-500 °C, this center transforms to a second configuration which is observed in darkness and can be changed back to the first configuration under illumination. Based on the observed 29Si and 13C hyperfine structures, two observed configurations of the EPR center were suggested to be related to different configurations of a carbon interstitial cluster. The annealing, bistable behaviors and energy levels of this EPR center are discussed.
Download or read book Electron Paramagnetic Resonance written by Victor Chechik and published by Royal Society of Chemistry. This book was released on 2018-11-02 with total page 187 pages. Available in PDF, EPUB and Kindle. Book excerpt: Electron Paramagnetic Resonance (EPR) applications remain very significant in modern analytical science and this volume compiles critical coverage of developments in the recent literature by a handpicked group of researchers at the cutting-edge of the field. The topics covered in this volume describe contrasting types of EPR application, including light induced hyperpolarization and disordered proteins to spin labels and nanomaterials. Providing a snap shot of the area, this book is a useful addition to any library supporting this research.
Download or read book Electron Paramagnetic Resonance Investigations of Biological Systems by Using Spin Labels Spin Probes and Intrinsic Metal Ions Part B written by and published by Academic Press. This book was released on 2015-10-08 with total page 659 pages. Available in PDF, EPUB and Kindle. Book excerpt: Electron Paramagnetic Resonance Investigations of Biological Systems by Using Spin Labels, Spin Probes, and Intrinsic Metal Ions Part A & B, are the latest volumes in the Methods in Enzymology series, continuing the legacy of this premier serial with quality chapters authored by leaders in the field. This volume covers research methods centered on the use of Electron Paramagnetic Resonance (EPR) techniques to study biological structure and function. Timely contribution that describes a rapidly changing field Leading researchers in the field Broad coverage: Instrumentation, basic theory, data analysis, and applications
Download or read book Electron Paramagnetic Resonance with Applications to Selected Problems in Biology written by George Feher and published by . This book was released on 1970 with total page 156 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Electron Paramagnetic Resonance in Biochemistry and Medicine written by Rafik Galimzyanovich Sajfutdinov and published by Springer Science & Business Media. This book was released on 2006-04-11 with total page 276 pages. Available in PDF, EPUB and Kindle. Book excerpt: Electron Paramagnetic Resonance (EPR) spectroscopy - also sometimes termed Electron Spin Resonance spectroscopy - has manifold potential uses in biochemistry and medicine. The paramount importance of EPR spectroscopy applied to biological tissues and fluids is that it identifies the changes in redox processes that contribute to disease. EPR spectroscopy has come a long way from its original use to detect malignant tumors. For example, the development and later refinement of methods of low-temperature registration of biological tissues widened the scope of EPR spectroscopy. Innovations made possible by the introduction of spin labels, probes, and traps made EPR spectroscopy ever more applicable to biochemistry and medicine, to the point where in vivo studies are being carefully considered. This comprehensive book discusses spectra of many tissues and bodily fluids, and the quantitative nature of paramagnetic centers in both normal individuals and patients suffering from a variety of diseases. Special attention is given to the EPR examination of bio-molecules, such as enzymes, polypeptides, vitamins, lipids, hydrocarbons, etc., which play an essential role in human activity. This book will be of great interest to physicians specializing in many different areas. Similarly, biologists, biochemists, biophysicists, and chemists will find this book very useful. It has also been written so that it may be used as a textbook at graduate level.
Download or read book Electron Paramagnetic Resonance Spectroscopy written by Patrick Bertrand and published by Springer Nature. This book was released on 2020-02-03 with total page 420 pages. Available in PDF, EPUB and Kindle. Book excerpt: Although originally invented and employed by physicists, electron paramagnetic resonance (EPR) spectroscopy has proven to be a very efficient technique for studying a wide range of phenomena in many fields, such as chemistry, biochemistry, geology, archaeology, medicine, biotechnology, and environmental sciences. Acknowledging that not all studies require the same level of understanding of this technique, this book thus provides a practical treatise clearly oriented toward applications, which should be useful to students and researchers of various levels and disciplines. In this book, the principles of continuous wave EPR spectroscopy are progressively, but rigorously, introduced, with emphasis on interpretation of the collected spectra. Each chapter is followed by a section highlighting important points for applications, together with exercises solved at the end of the book. A glossary defines the main terms used in the book, and particular topics, whose knowledge is not required for understanding the main text, are developed in appendices for more inquisitive readers.
Download or read book Electron Paramagnetic Resonance written by Bruce C Gilbert and published by Royal Society of Chemistry. This book was released on 2007-10-31 with total page 302 pages. Available in PDF, EPUB and Kindle. Book excerpt: Specialist Periodical Reports provide systematic and detailed review coverage of progress in the major areas of chemical research. Written by experts in their specialist fields the series creates a unique service for the active research chemist, supplying regular critical in-depth accounts of progress in particular areas of chemistry. For over 80 years the Royal Society of Chemistry and its predecessor, the Chemical Society, have been publishing reports charting developments in chemistry, which originally took the form of Annual Reports. However, by 1967 the whole spectrum of chemistry could no longer be contained within one volume and the series Specialist Periodical Reports was born. The Annual Reports themselves still existed but were divided into two, and subsequently three, volumes covering Inorganic, Organic and Physical Chemistry. For more general coverage of the highlights in chemistry they remain a 'must'. Since that time the SPR series has altered according to the fluctuating degree of activity in various fields of chemistry. Some titles have remained unchanged, while others have altered their emphasis along with their titles; some have been combined under a new name whereas others have had to be discontinued. The current list of Specialist Periodical Reports can be seen on the inside flap of this volume.
Download or read book Electron Paramagnetic Resonance written by Victor Chechik and published by Royal Society of Chemistry. This book was released on 2016-11-30 with total page 246 pages. Available in PDF, EPUB and Kindle. Book excerpt: The topics covered in this volume describe contrasting types of Electron Paramagnetic Resonance (EPR) application, including inorganic paramagnetic systems, spin-labeling in highly dynamic systems such as RNAs and IDPs and applications of nitroxides in host:guest chemistry. EPR applications remain very significant in modern science and this volume compiles critical coverage of developments in the recent literature by a hand-picked group of researchers at the cutting-edge of the field. Providing a snap shot of the area, this book is a useful addition to any library supporting this research.
Download or read book Electron Paramagnetic Resonance written by S. A. Al'tshuler and published by Academic Press. This book was released on 2013-10-22 with total page 383 pages. Available in PDF, EPUB and Kindle. Book excerpt: Electron Paramagnetic Resonance is a comprehensive text on the field of electron paramagnetic resonance, covering both the theoretical background and the results of experiment. This book is composed of eight chapters that cover theoretical materials and experimental data on ionic crystals, since these are the materials that have been most extensively studied by the methods of paramagnetic resonance. The opening chapters provide an introduction to the basic principles of electron paramagnetic resonance and the methods of its measurement. The next chapters are devoted to the theory of spectra and experimental studies of ionic crystals, as well as the complexity of construction of a shape theory of a paramagnetic resonance line. The remaining chapters discuss the application of electron paramagnetic resonance technique to the study of metals, semiconductors, defects in crystals, and free radicals.
Download or read book Electron Paramagnetic Resonance of Exchange Coupled Systems written by Alessandro Bencini and published by . This book was released on 1990 with total page 312 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Electron Paramagnetic Resonance written by John A. Weil and published by Wiley-Interscience. This book was released on 1994-03-28 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Focusing primarily on isolated paramagnetic species, Electron Paramagnetic Resonance is designed to provide senior undergraduate and graduate students as well as professionals with the essential understanding needed to use this technique and be active in various specialized fields of interest. Electron Paramagnetic Resonance enables those with no previous background in quantum mechanics to gain a fundamental grasp of EPR. It helps those with moderate training to acquire more sophisticated mathematical and quantum-mechanical skills and a knowledge of powerful theoretical and experimental techniques—tools that will allow them to interpret a wide range of EPR spectra. This important work also introduces many exciting new EPR developments in progress, including time-resolved spectroscopy, which involves the acquisition of EPR data for short-lived species. In addition, it highlights the increasing complexity of the experimental equipment currently used, including spectrometers that operate both in the classical continuous-wave mode and in pulsed mode. This book also discusses how computers can direct spectrometer control and data acquisition, analyze data to yield to underlying parameters, and produce accurate simulated spectra. Readers will acquire a heightened historical appreciation of the EPR technique, discovering how EPR studies have: confirmed the existence of triplet states, establishing that new adsorption bands observed in optical spectra following excitation by light of certain molecules arise from the unpairing of electron spins identified chlorophyll radicals as the primary donor in the photosynthesis process, as well as other key intermediates in this reaction clarified the structure and function of systems of biomedical interest, including oxygen carriers and various enzymes uncovered paramagnetic species in insulators and semiconductors and described their environment facilitated chemists' investigation of reaction mechanisms Complete with problem sets and concise bibliographies at the end of each chapter, as well as tutorial mathematical and quantum-mechanical appendices, this book is must reading for aspiring scientists in the field of physical chemistry and spectroscopy. Using this book, you will be able to gain a fundamental grasp of EPR—even if you have no previous background in quantum mechanics. This important work also helps those with some training to acquire more sophisticated mathematical and quantum-mechanical skills and a knowledge of powerful theoretical and experimental techniques—tools that will allow them to interpret a wide range of EPR spectra. You'll find out about many exciting new EPR developments in progress, including time-resolved spectroscopy, which involves the acquisition of EPR data for short-lived species. This book also discusses computers that direct spectrometer control and data acquisition, analyze data to yield to underlying parameters and produce accurate simulated spectra. Complete with problem sets and concise bibliographies at the end of each chapter, this book is must reading for aspiring scientists in the field of physical chemistry and spectroscopy.
Download or read book Spin Label Electron Paramagnetic Resonance Spectroscopy written by Derek Marsh and published by CRC Press. This book was released on 2019-12-09 with total page 472 pages. Available in PDF, EPUB and Kindle. Book excerpt: Spin-label electron paramagnetic resonance (EPR) spectroscopy is a versatile molecular probe method that finds wide application in molecular biophysics and structural biology. This book provides the first comprehensive summary of basic principles, spectroscopic properties, and use for studying biological membranes, protein folding, supramolecular structure, lipid-protein interactions, and dynamics. The contents begin with discussion of fundamental theory and practice, including static spectral parameters and conventional continuous-wave (CW) spectroscopy. The development then progresses, via nonlinear CW-EPR for slower motions, to the more demanding time-resolved pulse EPR, and includes an in-depth treatment of spin relaxation and spectral line shapes. Once the spectroscopic fundamentals are established, the final chapters acquire a more applied character. Extensive appendices at the end of the book provide detailed summaries of key concepts in magnetic resonance and chemical physics for the student reader and experienced practitioner alike. Key Features: Indispensable reference source for the understanding and interpretation of spin-label spectroscopic data in its different aspects. Tables of fundamental spectral parameters are included throughout. Forms the basis for an EPR graduate course, extending up to a thorough coverage of advanced topics in Specialist Appendices. Includes all necessary theoretical background. The primary audience is research workers in the fields of molecular biophysics, structural biology, biophysical chemistry, physical biochemistry and molecular biomedicine. Also, physical chemists, polymer physicists, and liquid-crystal researchers will benefit from this book, although illustrative examples used are often taken from the biomolecular field. Readers will be postgraduate researchers and above, but include those from other disciplines who seek to understand the primary spin-label EPR literature.
Download or read book Electron Paramagnetic Resonance written by Raymond S. Alger and published by . This book was released on 1968 with total page 610 pages. Available in PDF, EPUB and Kindle. Book excerpt:
