Download or read book Femtosecond Multidimensional Electronic and Raman Spectroscopy Towards the Study of Mn Complexes and the Oxygen Evolving Complexes and the Oxygen Evolving Complex written by and published by . This book was released on 2016 with total page 397 pages. Available in PDF, EPUB and Kindle. Book excerpt: The oxygen evolving complex of photosystem II is a tetramanganese complex that catalyzes the oxidation of water to dioxygen. Many experimental methods have been employed to study this complex, including a variety of spectroscopic methods. The complexity of the surrounding protein environment challenges reliable interpretation of the spectral features and discrimination between changes in the complex and the many cofactors of photosystem II. We have proposed coherent multidimensional spectroscopy in the mixed time-/frequency-domain as a strategy for exploring the spectroscopy of this important system. Coherent multidimensional spectroscopy is performed by the temporal synchronization and spatial overlap of a sequence of fields to induce a polarization in the material. The fields induced by polarizations meeting certain energy- and momentum-criteria are sampled; the intensity of the fields as functions of frequency and time elucidate the spectral and temporal characteristics of the sample's quantum states. Here, we describe efforts to extend the spectroscopy of model transition metal complexes to the femtosecond regime. We present the implementation of white-light transient absorption and demonstrate our ability to reproduce the spectroscopic behavior of manganese (III) tetraphenylporphine with improved time resolution over previously published results; we discuss the limitations encountered when extending this spectroscopy to homodyne-detected transient grating methods. We have implemented a strategy for broadband coherent anti-Stokes Raman spectroscopy, showing the results of these efforts. A theoretical background into the pulse propagation effects in the ultrafast regime of femtosecond spectroscopy has been compiled. We have found these propagation effects to have profound importance in the tuning and amplification of femtosecond pulses, and we present the results of simulations exploring how these effects manifest and influence the behavior of a particular process employed in light generation in a commercial traveling-wave optical parametric amplifier.
Download or read book Directory of Graduate Research written by American Chemical Society. Committee on Professional Training and published by . This book was released on 2005 with total page 1932 pages. Available in PDF, EPUB and Kindle. Book excerpt: Faculties, publications and doctoral theses in departments or divisions of chemistry, chemical engineering, biochemistry and pharmaceutical and/or medicinal chemistry at universities in the United States and Canada.
Download or read book Electronic Charge Transfer and Dynamics in Manganese and Iron Coordination Complexes Studied with Resonant Inelastic X ray Scattering written by Drew Alan Meyer and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: X-ray spectroscopy is a powerful tool in the study of electronic structure. I have utilized resonant inelastic x-ray scattering (RIXS) to study electronic charge transfer and electronic dynamics in transition metal complexes. RIXS creates a core-hole by scanning through the x-ray absorption edge while simultaneously measuring the emitted x-ray photons as the system relaxes to a lower energy core-hole state. RIXS is analogous to Resonance Raman spectroscopy but due to the properties of hard x-ray radiation, the tool is an elemental specific probe of electronic transitions. Charge transfer is a vital property of transition metal catalysts and I am able to assign RIXS spectral features to ligand-to-metal and metal-to-ligand charge transfer resonances and clearly characterize the nature of the molecular orbitals that are involved. I have also determined the effectiveness of extracting electronic dynamics from RIXS by carefully analyzing entire 1s3p RIXS data sets. The very short lifetime of the hard x-ray excited core-hole states means the RIXS process is sensitive to ultrafast electronic dynamics. The study of both charge transfer and electronic dynamics has been complimented by theoretical techniques to further the scientific understanding. The combination of RIXS measurements and density functional calculations allows the determination of the strength of the ligand-metal electronic interaction and assignment of the Raman resonances to charge transfer transitions in several manganese and iron cyanide complexes. With x-ray excitation energies resonant with the t2g and eg pre-edge peaks derived predominantly from the Mn 3d orbitals, the observation of Raman resonances in the energy transfer range from 2 to 12 eV which result from the filling of the 1s core-hole from t1u-symmetry occupied orbitals can be assigned as ligand-to-metal charge transfers. Evidence is also presented for the observation of a transition that leaves the state with increased electronic density in a ligand orbital while creating a metal hole, representing a metal-to-ligand charge transfer. The technique is then applied to K3Fe(CN)6, K4Fe(CN)6, and RbMnFe(CN)6. The two iron cyanides show similar results to those obtained with the manganese complex and the peak positions and relative intensities are discussed in relation to the electronic structure of the complexes. The manganese K-shell RIXS for RbMnFe(CN)6 shows significant deviation from the strong field metal-cyanide centers. The demonstration of the power of the technique on well characterized model systems opens the door for RIXS to be applied to more chemically relevant systems which is necessary for RIXS to develop widespread impact. I have also explored the potential for extracting excited state electron dynamics from RIXS spectra. This has involved detailed theoretical analysis of K3Mn(CN)6 and RbMnFe(CN)6 spectra. 'Core-hole clock' resonant soft x-ray studies have been utilized in the past to determine dynamic properties for a number of systems by relying on the lifetime of the excited core-hole. Due to the shortened lifetime of the hard x-ray excited core-holes, the technique is able to probe ultrafast electronic dynamics. The standard Kramer-Heisenberg description of RIXS attributes all dynamical effects to an excitation independent 1s core-hole lifetime and a final-state dependent lifetime broadening. Thorough study of the experimental data demonstrates that the standard implementation of the Kramers-Heisenberg formula cannot fully account for the experimentally observed excited state dynamics. We have proposed an alternative approach to analyzing RIXS spectra based on a density matrix formalism developed by Mukamel. The results demonstrate that while the Kramers-Heisenberg method is able to qualitatively model the spectra, it is unable to account for all aspects of the spectral dynamics within the RIXS spectrum. While the density matrix formalism is able to more accurately describe the spectral features in the RIXS, a more detailed theoretical understanding of the dynamics involved is necessary to robustly extract a dephasing time and better understand the ultrafast electronic response to core-hole creation.
Download or read book Synchrotron Light Sources and Free Electron Lasers written by Eberhard J. Jaeschke and published by Springer. This book was released on 2016-05-27 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Hardly any other discovery of the nineteenth century did have such an impact on science and technology as Wilhelm Conrad Röntgen’s seminal find of the X-rays. X-ray tubes soon made their way as excellent instruments for numerous applications in medicine, biology, materials science and testing, chemistry and public security. Developing new radiation sources with higher brilliance and much extended spectral range resulted in stunning developments like the electron synchrotron and electron storage ring and the freeelectron laser. This handbook highlights these developments in fifty chapters. The reader is given not only an inside view of exciting science areas but also of design concepts for the most advanced light sources. The theory of synchrotron radiation and of the freeelectron laser, design examples and the technology basis are presented. The handbook presents advanced concepts like seeding and harmonic generation, the booming field of Terahertz radiation sources and upcoming brilliant light sources driven by laser-plasma accelerators. The applications of the most advanced light sources and the advent of nanobeams and fully coherent x-rays allow experiments from which scientists in the past could not even dream. Examples are the diffraction with nanometer resolution, imaging with a full 3D reconstruction of the object from a diffraction pattern, measuring the disorder in liquids with high spatial and temporal resolution. The 20th century was dedicated to the development and improvement of synchrotron light sources with an ever ongoing increase of brilliance. With ultrahigh brilliance sources, the 21st century will be the century of x-ray lasers and their applications. Thus, we are already close to the dream of condensed matter and biophysics: imaging single (macro)molecules and measuring their dynamics on the femtosecond timescale to produce movies with atomic resolution.
Download or read book Excited State Molecular Structural Evolution and Chemical Reactivity Studied by Femtosecond Stimulated Raman Spectroscopy written by Fangyuan Han and published by . This book was released on 2014 with total page 167 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this dissertation, my research work on excited state dynamics of small organic molecules in solutions is presented. Using femtosecond stimulated Raman spectroscopy (FSRS) as the main experimental tool, the excited state hydrogen-bonding dynamics (ESHBD) of Coumarin 102, a common laser dye molecule, in ethanol solution is examined with
Download or read book Physics Briefs written by and published by . This book was released on 1994 with total page 1118 pages. Available in PDF, EPUB and Kindle. Book excerpt:
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 Chemical Abstracts written by and published by . This book was released on 2002 with total page 2626 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Light Harvesting in Photosynthesis written by Roberta Croce and published by CRC Press. This book was released on 2018-01-12 with total page 793 pages. Available in PDF, EPUB and Kindle. Book excerpt: This landmark collective work introduces the physical, chemical, and biological principles underlying photosynthesis: light absorption, excitation energy transfer, and charge separation. It begins with an introduction to properties of various pigments, and the pigment proteins in plant, algae, and bacterial systems. It addresses the underlying physics of light harvesting and key spectroscopic methods, including data analysis. It discusses assembly of the natural system, its energy transfer properties, and regulatory mechanisms. It also addresses light-harvesting in artificial systems and the impact of photosynthesis on our environment. The chapter authors are amongst the field’s world recognized experts. Chapters are divided into five main parts, the first focused on pigments, their properties and biosynthesis, and the second section looking at photosynthetic proteins, including light harvesting in higher plants, algae, cyanobacteria, and green bacteria. The third part turns to energy transfer and electron transport, discussing modeling approaches, quantum aspects, photoinduced electron transfer, and redox potential modulation, followed by a section on experimental spectroscopy in light harvesting research. The concluding final section includes chapters on artificial photosynthesis, with topics such as use of cyanobacteria and algae for sustainable energy production. Robert Croce is Head of the Biophysics Group and full professor in biophysics of photosynthesis/energy at Vrije Universiteit, Amsterdam. Rienk van Grondelle is full professor at Vrije Universiteit, Amsterdam. Herbert van Amerongen is full professor of biophysics in the Department of Agrotechnology and Food Sciences at Wageningen University, where he is also director of the MicroSpectroscopy Research Facility. Ivo van Stokkum is associate professor in the Department of Physics and Astronomy, Faculty of Sciences, at Vrije Universiteit, Amsterdam.
Download or read book Index to Theses with Abstracts Accepted for Higher Degrees by the Universities of Great Britain and Ireland and the Council for National Academic Awards written by and published by . This book was released on 2007 with total page 362 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Photosynthetic Excitons written by Herbert van Amerongen and published by World Scientific. This book was released on 2000 with total page 612 pages. Available in PDF, EPUB and Kindle. Book excerpt: Excitons are considered as the basic concept used by describing the spectral properties of photosynthetic pigment-protein complexes and excitation dynamics in photosynthetic light-harvesting antenna and reaction centers. Following the recently obtained structures of a variety of photosynthetic pigment-protein complexes from plants and bacteria our interest in understanding the relation between structure, function and spectroscopy has strongly increased. These data demonstrate a short interpigment distance (of the order of 1 nm or even smaller) and/or a highly symmetric (ring-like) arrangement of pigment molecules in peripheral light-harvesting complexes of photosynthetic bacteria. Books which were devoted to the exciton problem so far mainly considered the spectral properties of molecular crystals. However, the small size of these pigment aggregates in the pigment-protein complexes as well as the role of the protein, which is responsible for the structural arrangement of the complex, clearly will have a dramatic influence on the pigment spectra and exciton dynamics. All these aspects of the problem are considered in this book. Exciton theory is mainly considered for small molecular aggregates (dimers, ring-like structures etc.). Together with the theoretical description of the classical conceptual approach, which mainly deals with polarization properties of the absorption and fluorescence spectra, the nonlinear femtosecond spectroscopy which is widely used for investigations now is also discussed. A large part of the book demonstrates the excitonic effects in a multitude of photosynthetic pigment-protein complexes and how we can understand these properties on the basis of the exciton concept.
Download or read book Spectroscopy of Complex Oxide Interfaces written by Claudia Cancellieri and published by Springer. This book was released on 2018-04-09 with total page 326 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book summarizes the most recent and compelling experimental results for complex oxide interfaces. The results of this book were obtained with the cutting-edge photoemission technique at highest energy resolution. Due to their fascinating properties for new-generation electronic devices and the challenge of investigating buried regions, the book chiefly focuses on complex oxide interfaces. The crucial feature of exploring buried interfaces is the use of soft X-ray angle-resolved photoemission spectroscopy (ARPES) operating on the energy range of a few hundred eV to increase the photoelectron mean free path, enabling the photons to penetrate through the top layers – in contrast to conventional ultraviolet (UV)-ARPES techniques. The results presented here, achieved by different research groups around the world, are summarized in a clearly structured way and discussed in comparison with other photoemission spectroscopy techniques and other oxide materials. They are complemented and supported by the most recent theoretical calculations as well as results of complementary experimental techniques including electron transport and inelastic resonant X-ray scattering.
Download or read book Core Level Spectroscopy of Solids written by Frank de Groot and published by CRC Press. This book was released on 2008-03-10 with total page 512 pages. Available in PDF, EPUB and Kindle. Book excerpt: Core level spectroscopy has become a powerful tool in the study of electronic states in solids. From fundamental aspects to the most recent developments, Core Level Spectroscopy of Solids presents the theoretical calculations, experimental data, and underlying physics of x-ray photoemission spectroscopy (XPS), x-ray absorption spectroscopy (XAS), x
Download or read book Surface Enhanced Raman Scattering written by Zhong-Qun Tian and published by John Wiley & Sons Incorporated. This book was released on 2010-06-14 with total page 400 pages. Available in PDF, EPUB and Kindle. Book excerpt: Surface-Enhanced Raman Spectroscopy: Principles, Experiments, and Applications is a comprehensive, up to date, and balanced treatment of the theoretical and practical aspects of Surface-Enhanced Raman Scattering (SERS), a useful branch of spectroscopy for several areas of science. This book describes the basic principles of SERS, including SERS mechanisms, performing SERS measurements, and interpreting data. Also emphasized are applications in electrochemistry; catalysis; surface processing and corrosion; Self-Assemble-Layer and L-B Films; polymer science; biology; medicine and drug analysis; sensors; fuel cells; forensics; and archaeology. It is an essential guide for student and professional analytical chemists.
Download or read book Fundamentals of Semiconductors written by Peter YU and published by Springer Science & Business Media. This book was released on 2007-05-08 with total page 651 pages. Available in PDF, EPUB and Kindle. Book excerpt: Excellent bridge between general solid-state physics textbook and research articles packed with providing detailed explanations of the electronic, vibrational, transport, and optical properties of semiconductors "The most striking feature of the book is its modern outlook ... provides a wonderful foundation. The most wonderful feature is its efficient style of exposition ... an excellent book." Physics Today "Presents the theoretical derivations carefully and in detail and gives thorough discussions of the experimental results it presents. This makes it an excellent textbook both for learners and for more experienced researchers wishing to check facts. I have enjoyed reading it and strongly recommend it as a text for anyone working with semiconductors ... I know of no better text ... I am sure most semiconductor physicists will find this book useful and I recommend it to them." Contemporary Physics Offers much new material: an extensive appendix about the important and by now well-established, deep center known as the DX center, additional problems and the solutions to over fifty of the problems at the end of the various chapters.
Download or read book Transition Metals in Coordination Environments written by Ewa Broclawik and published by Springer. This book was released on 2019-03-16 with total page 532 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book focuses on the electronic properties of transition metals in coordination environments. These properties are responsible for the unique and intricate activity of transition metal sites in bio- and inorganic catalysis, but also pose challenges for both theoretical and experimental studies. Written by an international group of recognized experts, the book reviews recent advances in computational modeling and discusses their interplay using experiments. It covers a broad range of topics, including advanced computational methods for transition metal systems; spectroscopic, electrochemical and catalytic properties of transition metals in coordination environments; metalloenzymes and biomimetic compounds; and spin-related phenomena. As such, the book offers an invaluable resource for all researchers and postgraduate students interested in both fundamental and application-oriented research in the field of transition metal systems.
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
