Download or read book A Semiempirical Approach for Resonance Raman Intensities written by Gerald Michael Korenowski and published by . This book was released on 1979 with total page 402 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1992 with total page 1572 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Semiempirical Methods of Electronic Structure Calculation written by Gerald Segal and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 285 pages. Available in PDF, EPUB and Kindle. Book excerpt: If one reflects upon the range of chemical problems accessible to the current quantum theoretical methods for calculations on the electronic structure of molecules, one is immediately struck by the rather narrow limits imposed by economic and numerical feasibility. Most of the systems with which experimental photochemists actually work are beyond the grasp of ab initio methods due to the presence of a few reasonably large aromatic ring systems. Potential energy surfaces for all but the smallest molecules are extremely expensive to produce, even over a restricted group of the possible degrees of freedom, and molecules containing the higher elements of the periodic table remain virtually untouched due to the large numbers of electrons involved. Almost the entire class of molecules of real biological interest is simply out of the question. In general, the theoretician is reduced to model systems of variable appositeness in most of these fields. The fundamental problem, from a basic computational point of view, is that large molecules require large numbers of basis functions, whether Slater type orbitals or Gaussian functions suitably contracted, to provide even a modestly accurate description of the molecular electronic environment. This leads to the necessity of dealing with very large matrices and numbers of integrals within the Hartree-Fock approximation and quickly becomes both numerically difficult and uneconomic.
Download or read book Vibrational Intensities written by B.S. Galabov and published by Elsevier. This book was released on 1996-11-22 with total page 322 pages. Available in PDF, EPUB and Kindle. Book excerpt: The current volume is a single topic volume on the vibrational intensities in the infrared and Raman spectra. Vibrational intensities in infrared and Raman spectra are important physical quantities that are directly related to the distribution and fluctuations of electric charges in the molecule. These spectral parameters can be experimentally determined with good accuracy for many molecules. Additionally, infrared and Raman intensities are presently estimated theoretically by advanced analytical derivative ab initio molecular orbital methods. These fundamental molecular quantities are being used in structural, and other studies, on a limited basis. Features of this book - Presents in a systematic way, the theoretical approaches that are used in analyzing and predicting vibrational intensities - The formalisms developed are illustrated with detailed numerical examples - Most of the theoretical models described were obtained and then applied to chosen molecules - A consistent notation is used in presenting the different theoretical approaches, thus eliminating another barrier in understanding some methods, especially those developed by the Russian spectroscopic school.
Download or read book Dissertation Abstracts International written by and published by . This book was released on 2007 with total page 1044 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Raman Spectroscopy An Intensity Approach written by Guozhen Wu and published by World Scientific. This book was released on 2016-08-18 with total page 225 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book summarizes the highlights of our work on the bond polarizability approach to the intensity analysis. The topics covered include surface enhanced Raman scattering, Raman excited virtual states and Raman optical activity (ROA). The first chapter briefly introduces the Raman effect in a succinct but clear way. Chapter 2 deals with the normal mode analysis. This is a basic tool for our work. Chapter 3 introduces our proposed algorithm for the Raman intensity analysis. Chapter 4 heavily introduces the physical picture of Raman virtual states. Chapter 5 offers details so that the readers can have a comprehensive idea of Raman virtual states. Chapter 6 demonstrates how this bond polarizability algorithm is extended to ROA intensity analysis. Chapters 7 and 8 offer details on ROA, showing many findings on ROA mechanism that were not known or neglected before. Chapter 9 introduces our proposed classical treatment on ROA which, as combined with the results from the bond polarizability analysis, leads to a comprehensive physical picture for the Raman effect. In particular, this classical treatment unifies ROA and VCD (vibrational circular dichroism) on equal footing. In each section, Comments summarize the key ideas and their evaluation. This will help the readers to capture the core ideas of the presentations.
Download or read book Excited State Structure and Dynamics from Resonance Raman Intensity Analysis written by Christina Marie Stuart and published by . This book was released on 2007 with total page 416 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Modern Raman Spectroscopy written by Ewen Smith and published by John Wiley & Sons. This book was released on 2013-03-15 with total page 248 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book reflects the dramatic increase in the number of Raman spectrometers being sold to and used by non-expert practitioners. It contains coverage of Resonance Raman and SERS, two hot areas of Raman, in a form suitable for the non-expert. Builds Raman theory up in stages without overloading the reader with complex theory Includes two chapters on instrumentation and interpretation that shows how Raman spectra can be obtained and interpreted Explains the potential of using Raman spectroscopy in a wide variety of applications Includes detailed, but concise information and worked examples
Download or read book Calculation of Absolute Resonance Raman Intensities written by Krista A. Kane and published by . This book was released on 2009 with total page 49 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Biomedical Vibrational Spectroscopy written by Peter Lasch and published by John Wiley & Sons. This book was released on 2008-06-27 with total page 403 pages. Available in PDF, EPUB and Kindle. Book excerpt: This comprehensive overview of biomedical applications of vibrational spectroscopy focuses on methodologies that are most relevant to biodiagnostics. After a few introductory chapters that summarize the current status of the field, the reference covers current spectroscopic applications; new spectroscopic directions; and study design and the analysis of vibrational spectral fingerprints from complex biological and clinical samples . With chapters contributed by leading international experts, Biomedical Vibrational Spectroscopy is a core resource.
Download or read book Excited State Structure and Dynamics from Absolute Resonance Raman Intensities written by Mary Katherine Lawless and published by . This book was released on 1993 with total page 538 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book American Doctoral Dissertations written by and published by . This book was released on 1978 with total page 620 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Theory and Applications of Computational Chemistry written by Clifford Dykstra and published by Elsevier. This book was released on 2011-10-13 with total page 1336 pages. Available in PDF, EPUB and Kindle. Book excerpt: Computational chemistry is a means of applying theoretical ideas using computers and a set of techniques for investigating chemical problems within which common questions vary from molecular geometry to the physical properties of substances. Theory and Applications of Computational Chemistry: The First Forty Years is a collection of articles on the emergence of computational chemistry. It shows the enormous breadth of theoretical and computational chemistry today and establishes how theory and computation have become increasingly linked as methodologies and technologies have advanced. Written by the pioneers in the field, the book presents historical perspectives and insights into the subject, and addresses new and current methods, as well as problems and applications in theoretical and computational chemistry. Easy to read and packed with personal insights, technical and classical information, this book provides the perfect introduction for graduate students beginning research in this area. It also provides very readable and useful reviews for theoretical chemists. * Written by well-known leading experts * Combines history, personal accounts, and theory to explain much of the field of theoretical and compuational chemistry * Is the perfect introduction to the field
Download or read book Structures and Conformations of Non Rigid Molecules written by J. Laane and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 640 pages. Available in PDF, EPUB and Kindle. Book excerpt: From the beginnings of modern chemistry, molecular structure has been a lively area of research and speculation. For more than half a century spectroscopy and other methods have been available to characterize the structures and shapes of molecules, particularly those that are rigid. However, most molecules are at least to some degree non-rigid and this non-rigidity plays an important role in such diverse areas as biological activity, energy transfer, and chemical reactivity. In addition, the large-amplitude vibrations present in non-rigid molecules give rise to unusual low-energy vibrational level patterns which have a dramatic effect on the thermodynamic properties of these systems. Only in recent years has a coherent picture of the energetics and dynamics of the conformational changes inherent in non-rigid (and semi-rigid) molecules begun to emerge. Advances have been made in a number of different experimental areas: vibrational (infrared and Raman) spectroscopy, rotational (microwave) spectroscopy, electron diffraction, and, most recently, laser techniques probing both the ground and excited electronic states. Theoretically, the proliferation of powerful computers coupled with scientific insight has allowed both empirical and ab initio methods to increase our understanding of the forces responsible for the structures and energies of non-rigid systems. The development of theory (group theoretical methods and potential energy surfaces) to understand the unique characteristics of the spectra of these floppy molecules has also been necessary to reach our present level of understanding. The thirty chapters in this volume contributed by the key speakers at the Workshop are divided over the various areas. Both vibrational and rotational spectroscopy have been effective at determining the potential energy surfaces for non-rigid molecules, often in a complementary manner. Recent laser fluorescence work has extended these types of studies to electronic excited states. Electronic diffraction methods provide radial distribution functions from which both molecular structures and compositions of conformational mixtures can be found. Ab initio calculations have progressed substantially over the past few years, and, when carried out at a sufficiently high level, can accurately reproduce (or predict ahead of time) experimental findings. Much of the controversy of the ARW related to the question of when an ab initio is reliable. Since the computer programs are readily available, many poor calculations have been carried out. However, excellent results can be obtained from computations when properly done. A similar situation exists for experimental analyses. The complexities of non-rigid molecules are many, but major strides have been taken to understand their structures and conformational processes.
Download or read book Analysis of Vibronic Structure and Resonance Raman Intensities in Electron Transfer Spectra Involving Multiple Interacting Surfaces written by Susan Elizabeth Bailey and published by . This book was released on 2004 with total page 326 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Chemical and Biochemical Applications of Lasers V4 written by C. Bradley Moore and published by Elsevier. This book was released on 2012-12-02 with total page 427 pages. Available in PDF, EPUB and Kindle. Book excerpt: Chemical and Biochemical Applications of Lasers, Volume IV focuses on the practical applications of standard commercial laser systems. This book examines the structural studies of DNA by fluorescence microscopy and discusses photochemistry and structural spectroscopy. Organized into eight chapters, this volume starts with an overview of a few cases of laser-induced fluorescence studies of biological molecules. This text then examines the sharp fluorescence spectra of complex molecules in solids that are obtained when a narrow-band laser selectively excites molecules in particular sites. Other chapters describe the theory and application of resonance Raman spectroscopy to various biological systems. This book provides as well a thorough treatment of coherent anti-Stokes Raman spectroscopy and its application in combustion diagnostics and analytical chemistry. The final chapter explores laser control of the sequential photochemical reaction of the drug psoralen with the two strands of the DNA double helix. Physicists, chemists, electrochemists, and chemical engineers will find this book useful.
Download or read book Resonance Raman Spectra of Polyenes and Aromatics written by Thomas G. Spiro and published by Wiley-Interscience. This book was released on 1987 with total page 392 pages. Available in PDF, EPUB and Kindle. Book excerpt:
