[PDF] Excited States eBook

Author : Leticia González
Publisher : John Wiley & Sons
Page : 52 pages
File Size : 27,16 MB
Release : 2021-02-01
Category : Science
ISBN : 1119417759

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An introduction to the rapidly evolving methodology of electronic excited states For academic researchers, postdocs, graduate and undergraduate students, Quantum Chemistry and Dynamics of Excited States: Methods and Applications reports the most updated and accurate theoretical techniques to treat electronic excited states. From methods to deal with stationary calculations through time-dependent simulations of molecular systems, this book serves as a guide for beginners in the field and knowledge seekers alike. Taking into account the most recent theory developments and representative applications, it also covers the often-overlooked gap between theoretical and computational chemistry. An excellent reference for both researchers and students, Excited States provides essential knowledge on quantum chemistry, an in-depth overview of the latest developments, and theoretical techniques around the properties and nonadiabatic dynamics of chemical systems. Readers will learn: ● Essential theoretical techniques to describe the properties and dynamics of chemical systems ● Electronic Structure methods for stationary calculations ● Methods for electronic excited states from both a quantum chemical and time-dependent point of view ● A breakdown of the most recent developments in the past 30 years For those searching for a better understanding of excited states as they relate to chemistry, biochemistry, industrial chemistry, and beyond, Quantum Chemistry and Dynamics of Excited States provides a solid education in the necessary foundations and important theories of excited states in photochemistry and ultrafast phenomena.

Author : Martin Klessinger
Publisher : VCH Publishers
Page : 576 pages
File Size : 31,28 MB
Release : 1995
Category : Science
ISBN :

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A significantly updated translation of Lichtabsorption und Photochemie Organischer Molekule, published by VCH in 1989. A graduate textbook that provides a qualitative description of electronic excitation in organic molecules and of the associated spectroscopy, photophysics, and photochemistry. The treatment is non- mathematical and emphasizes the use of simple qualitative models for developing an intuitive feeling for the course of photophysical and photochemical processes in terms of potential energy hypersurfaces. Special attention is paid to recent developments, particularly to the role of conical intersections. Annotation copyright by Book News, Inc., Portland, OR

Author : Nicolas Ferré
Publisher : Springer
Page : 487 pages
File Size : 42,78 MB
Release : 2015-08-26
Category : Science
ISBN : 3319220810

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The series Topics in Current Chemistry presents critical reviews of the present and future trends in modern chemical research. The scope of coverage is all areas of chemical science including the interfaces with related disciplines such as biology, medicine and materials science. The goal of each thematic volume is to give the non-specialist reader, whether in academia or industry, a comprehensive insight into an area where new research is emerging which is of interest to a larger scientific audience. Each review within the volume critically surveys one aspect of that topic and places it within the context of the volume as a whole. The most significant developments of the last 5 to 10 years are presented using selected examples to illustrate the principles discussed. The coverage is not intended to be an exhaustive summary of the field or include large quantities of data, but should rather be conceptual, concentrating on the methodological thinking that will allow the non-specialist reader to understand the information presented. Contributions also offer an outlook on potential future developments in the field. Review articles for the individual volumes are invited by the volume editors. Readership: research chemists at universities or in industry, graduate students

Author : Michael A. Robb
Publisher : Royal Society of Chemistry
Page : 240 pages
File Size : 20,7 MB
Release : 2018-03-02
Category : Science
ISBN : 1782628649

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This reference is ideal for both theorists and experimentalists working in theoretical chemistry, electronic structure and molecular dynamics

Author : Melvin Robin
Publisher : Elsevier
Page : 391 pages
File Size : 13,6 MB
Release : 2012-12-02
Category : Science
ISBN : 0323152597

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Higher Excited States of Polyatomic Molecules, Volume I focuses on the spectra in the vacuum-ultraviolet region between 50,000 and 100,000 cm-1. This book explores the higher excitations in molecules beyond 50,000 cm-1. Organized into three chapters, this volume starts with an overview of the excited-state properties of a molecule and the excited-state ionization potential. This book then proceeds with a discussion of the original classification of the properties as well as the types of excitations observed in the vacuum-ultraviolet. Other chapters discuss photoelectron spectroscopy, which is an independent, self-sustaining branch of molecular spectroscopy. This text examines as well the distinction between valence shell and Rydberg excitations. The final chapter deals with several topics, including the saturated molecules that are classified as having all valence electrons, the alkene absorption spectra, and the spectroscopic data on boron compounds. Analytical chemists, photochemists, molecular spectroscopists, and researchers will find this book extremely useful.

Author : Edward Lim
Publisher : Elsevier
Page : 217 pages
File Size : 42,27 MB
Release : 2012-12-02
Category : Science
ISBN : 0323159982

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Excited States, Volume 5 consists of three concise and detailed chapters. These chapters cover the topics of excited-state potential surfaces of polyatomic molecules; vibronic spectroscopy of benzene; and quantum statistical mechanical (QSM) theory for molecular relaxation processes. Chapter 1 discusses excited-state potential surfaces with focus on ab initio calculations. Simple methods of computational schemes are also presented in this chapter. Chapter 2 reviews the excited electronic states of benzene. This chapter also includes the basic theory of benzene electronic excitations and the various types of spectroscopy (absorption, vibrational Raman, and electron-impact). Lastly, Chapter 3 presents a unified QSM theory, phenomenological theory of irreversible thermodynamics, and kinetics. The focus of QSM theory is on the nonlinear domain and is used to construct a nonlinear theory for the relaxation of excited molecules that are electric, vibrating, and rotating. This volume is a good reference for students and researchers studying in the field of chemistry and physics.

Author : Renata Reisfeld
Publisher : Springer Science & Business Media
Page : 235 pages
File Size : 41,79 MB
Release : 2012-12-06
Category : Science
ISBN : 3642666965

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The possibility of stimulated light emission was discussed by Einstein in 1917, eight years before the quantum-mechanical description of energy levels of many-electron systems. Though it is imperative to use samples having optical properties greatly different from the stan dard continuous spectrum of opaque objects ("black body" radia tion) it is not always necessary to restrict the study to monatomic entities. Thus, spectral lines can be obtained (in absorption and in emission) from lanthanide compounds, containing from one to thir teen 4f electrons going from trivalent cerium to ytterbium, that are nearly as sharp as the ones from gaseous atoms. However, the presence of adjacent atoms modifies the simple picture of an isolated electron configuration, and in particular, it is possible to pump excited levels efficiently by energy transfer from species with intense absorption bands, such as the inter-shell transitions of other lanthanides and of thallium(I), lead(II) and bismuth(III) or the electron transfer bands of the uranyl ion or other complexes. On the other hand, it is possible to diminuish the mUlti-phonon relaxation (competing with sharp line luminescence) by selecting vitreous or crystalline materials with low phonon energies. Obviously, one cannot circumvent the conservation of energy by lasers, but they may have unprecedented consequences for the future by allowing nuclear fusion of light elements, effects of non-linear optics and time-resolved spectroscopy, besides the more conventional applications of coherent light beams with negligible angular extension.

Author : Cleanthes A. Nicolaides
Publisher : Springer Science & Business Media
Page : 572 pages
File Size : 32,68 MB
Release : 2012-12-06
Category : Science
ISBN : 940099902X

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It is undoubtedly true that much of the progress in the quant~m theory of matter is due to the remarkable success of the independent particle model (IPM)--especially in describing ground states. However, the accurate experimental results of the last 10 years or so, on a variety of spectroscopic phenomena and chemical processes which involve the Excited State, and the related failure of the IPM to reproduce accurately--in many cases, even qualitatively--the observed data, have sent to theorists a clear message: There is need to create and/or apply general and useful approaches to the many-electron problem of the excited state which go beyond the IPM, treat electron correlation and relativity and explain or predict all relevant physical or chemical information with consistent accuracy. This book contains articles devoted mainly to some of the most important new developments in Quantum Chemistry concerning the theoretical foundations and the computational implementation of many-body approaches to the quantitative and detailed under standing of the electronic excited states of atoms, molecules and solids. Furthermore, it contains experimental and pheno menological articles on Photoelectron and Auger spectroscopy, Lifetime measurements and Organic Photochemistry. In combination or individually, these articles constitute a good description of some current theoretical and experimental work on the electronic structure and spectroscopy of atoms, molecules, polymers, surfaces, metal oxides and amorphous solids.

Author : Edward C. Lim
Publisher : Elsevier
Page : 237 pages
File Size : 32,73 MB
Release : 2013-10-22
Category : Science
ISBN : 1483275485

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Excited States, Volume 6 is a collection of papers that discusses the excited states of molecules. The first paper discusses the linear polyene electronic structure and potential surfaces, considering both the theoretical and experimental approaches in such electronic states. This paper also reviews the theory of electronic structure and cites some experimental techniques on polyene excitations, polyene spectroscopic phenomenology, and those involving higher states of polyenes and their triplet states. Examples of these experimental studies of excited states involve the high-resolution one-photon absorption spectroscopy, two photon spectroscopy, electron-impact spectroscopy, radiationless decay rates, and radiative fluorescence lifetimes. Some unresolved issues remain such as the resolution of the excited-state order in butadiene and the two isomers of hexatriene. The second paper describes the energetics and scattering of mixed exciton-photon states in organic crystals that should form part of future research in the field of organic solids. This paper also describes mixed exciton-photon states, exciton-phonon, and polariton-phonon scattering. This book will prove invaluable for researchers and scientists working in the field of micro-chemistry and solid-state physics.

Author : Baldassare di Bartolo
Publisher : Springer Science & Business Media
Page : 749 pages
File Size : 10,6 MB
Release : 2012-12-06
Category : Science
ISBN : 146153044X

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This book presents an account of the course "Optical Properties of Excited States in Solids" held in Erice, Italy, from June 16 to 3D, 1991. This meeting was organized by the International School of Atomic and Molecular Spectroscopy of the "Ettore Majorana" Centre for Scientific Culture. The purpose of this course was to present physical models, mathematical formalisms and experimental techniques relevant to the optical properties of excited states in solids. Some active physical species, such as ions or radicals, could survive indefinitely if they were completely 'isolated in space. Other active species, such as excited molecular and solid-state systems, are inherently unstable, even in isolation, due to the spontaneous mechanisms that may convert their excitation energies into radiation or heat. Physical parameters that may be used to characterize these excited systems are the localization or delocalization, and the coherence or incoherence, of their state excitations. In solids the excited states, whether they are localized (as for impurities in insulators) or delocalized (as they may occur in semiconductors), are relevant in several regards. Their de-excitation is extremely sensitive to the nature of the excitations of the systems, and a study of the de-excitation processes can yield a variety of information. For example, the excited states may represent the initial condition of the onset of such processes as Stokes-shifted emission, hot luminescence, symmetry-dependent Jahn-Teller and scattering processes, tunneling processes, energy transfer to like and unlike centers, superradiance, coherent radiation, and excited state absorption.