Download or read book Photoionization of Excited Molecular States Using Multiphoton Excitation Techniques written by and published by . This book was released on 1984 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Photoelectron spectra are reported for three photon resonant, four photon ionization of H2 via the B 1.sigma./sub u/, v = 7 (J = 2,4) and C 1.pi./sub u'/, v = 0-4 (J = 1) levels and of N2 via the o31.pi./sub u'/, v = 1,2, b 1.pi./sub u'/, v = 3-5, and c 1.pi./sub u'/, v = 0 levels. The results reflect both the spectroscopy and the dynamics of photoionization of excited molecular states and are discussed in terms of the selection rules for photoionization and the relative probabilities of photoionization from Rydberg and valence states. In some cases, in accordance with the Franck-Condon principle, the results demonstrate that resonant multiphoton ionization through Rydberg states may be a powerful technique for the production of electronic, vibrational, and rotational state selected ions. However, in other cases, systematic departures from Franck-Condon factors are observed, which reflect the more subtle dynamics of excited state photoionization. 23 references, 6 figures, 2 tables.
Download or read book Structure and Dynamics of Electronic Excited States written by Jaan Laane and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 324 pages. Available in PDF, EPUB and Kindle. Book excerpt: New developments in laser technology and theoretical modeling has allowed physicists to control chemical reactions using lasers and to attain an understanding of the underlying photochemical reaction mechanism. The book gives an up-to-date presentation of this research area, covering time-resolved spectroscopy and the dynamical behavior of electronically excited states.
Download or read book Photoabsorption Photoionization and Photoelectron Spectroscopy written by Joseph Berkowitz and published by Academic Press. This book was released on 2012-12-02 with total page 490 pages. Available in PDF, EPUB and Kindle. Book excerpt: Photoabsorption, Photoionization, and Photoelectron Spectroscopy explores photoabsorption processes involving individual, isolated molecules in the wavelength or photon energy range from the ionization thresholds of molecules (usually in the vacuum ultraviolet region) through the soft and hard X-ray region and beyond the ""K edge."" The interaction between electromagnetic radiation and isolated molecules based on photoabsorption, photoionization, and photoelectron spectroscopy studies is described, along with the techniques for measurement of total and partial cross sections. This book is comprised of eight chapters and examines the decomposition of molecules and molecular ions as well as mildly excited (valence shell excitation) and highly excited (inner shell excitation) molecules. After providing a general theoretical background, it discusses certain classes of atoms and molecules and considers electromagnetic interactions with gases. The following chapters focus on photoabsorption below the first ionization limit; quasi-discrete states above the first ionization potential; and the ionization continuum. Total photoabsorption and photoionization cross sections for selected molecules are also considered, and the angular distribution of photoelectrons is analyzed. The various measurement techniques are described in the last chapter. This monograph will be of interest to radiation chemists, radiation physicists, photochemists, mass spectrometrists, and perhaps radiation biologists.
Download or read book Laser Photoionization Spectroscopy written by Vladilen Letokhov and published by Elsevier. This book was released on 2012-12-02 with total page 364 pages. Available in PDF, EPUB and Kindle. Book excerpt: Laser Photoionization Spectroscopy discusses the features and the development of photoionization technique. This book explores the progress in the application of lasers, which improve the characteristics of spectroscopic methods. Organized into 12 chapters, this book starts with an overview of the fundamentals of the method for atoms and molecules. This text then examines the photoionization spectroscopy, which is based on the laser resonant excitation of particles into high-lying quantum states that are easy to detect by ionization. Other chapters explain the various basic schemes of multistep excitation, which can be used for resonance photoionization of molecules. This book discusses as well the different applications of the resonance photoionization technique in atomic and molecular spectroscopy. The final chapter considers the two well-known types of microscopy, namely, wave and corpuscular. This book is a valuable resource for chemists, physicists, analysts, and geochemists who are interested in laser spectroscopy techniques to solve nontrivial problems.
Download or read book Photoionization of Excited Molecular States written by and published by . This book was released on 1984 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Rapid advances in laser and detector technologies are making it possible to investigate molecular photophysics and photochemistry in powerful new ways. For example, resonantly enhanced multiphoton ionization (REMPI) measurements, in which the total (or the mass selected) ion current is monitored as a function of laser wavelength, have yielded extensive and often novel information on the spectroscopy of the resonant intermediate states. With the addition of photoelectron spectrometry (PES) to analyze the kinetic energy of the ejected electrons, it is possible to determine the branching ratios into different electronic, vibrational, and rotational levels of the product ion and to focus directly on both the dynamics of the multiphoton ionization process and the photoionization of excited state species. In the present paper, we report several REMPI/PES studies of H2 and N2. The results reflect both the spectroscopy and the dynamics of photoionization of excited molecular states and are discussed in terms of the selection rules for photoionization and the relative probabilities of photoionization from Rydberg and valence states. In some cases, in accordance with the Franck-Condon principle, the results demonstrate that resonant multiphoton ionization through Rydberg states may be a powerful technique for the production of electronic, vibrational, and rotational state selected ions. However, in other cases, systematic departures from Franck-Condon behavior are observed, which reflect the more subtle dynamics of excited state photoionization.
Download or read book Photoionization and Photodetachment written by Cheuk-Yiu Ng and published by World Scientific. This book was released on 2000 with total page 731 pages. Available in PDF, EPUB and Kindle. Book excerpt: Owing to the advances of vacuum ultraviolet and ultrafast lasers and third generation synchrotron sources, the research on photoionization, photoelectrons, and photodetachment has gained much vitality in recent years. These new light sources, together with ingenious experimental techniques, such as the coincidence imaging, molecular beam, pulsed field ionization photoelectron, mass-analyzed threshold ion, and pulsed field ion pair schemes, have allowed spectroscopic, dynamic, and energetic studies of gaseous species to a new level of detail and accuracy. Profitable applications of these methods to liquids are emerging.This invaluable two-volume review consists of twenty-two chapters, focusing on recent developments in photoionization and photodetachment studies of atoms; molecules, transient species, clusters, and liquids.
Download or read book Photoionization and Photodetachment written by Cheuk-Yiu Ng and published by World Scientific. This book was released on 2000 with total page 1415 pages. Available in PDF, EPUB and Kindle. Book excerpt: Owing to the advances of vacuum ultraviolet and ultrafast lasers and third generation synchrotron sources, the research on photoionization, photoelectrons, and photodetachment has gained much vitality in recent years. These new light sources, together with ingenious experimental techniques, such as the coincidence imaging, molecular beam, pulsed field ionization photoelectron, mass-analyzed threshold ion, and pulsed field ion pair schemes, have allowed spectroscopic, dynamic, and energetic studies of gaseous species to a new level of detail and accuracy. Profitable applications of these methods to liquids are emerging.This invaluable two-volume review consists of twenty-two chapters, focusing on recent developments in photoionization and photodetachment studies of atoms; molecules, transient species, clusters, and liquids.
Download or read book Molecular Conformation and Organic Photochemistry written by Rasmus Y. Brogaard and published by Springer Science & Business Media. This book was released on 2012-05-17 with total page 129 pages. Available in PDF, EPUB and Kindle. Book excerpt: Rasmus Brogaard's thesis digs into the fundamental issue of how the shape of a molecule relates to its photochemical reactivity. This relation is drastically different from that of ground-state chemistry, since lifetimes of excited states are often comparable to or even shorter than the time scales of conformational changes. Combining theoretical and experimental efforts in femto-second time-resolved photoionization Rasmus Brogaard finds that a requirement for an efficient photochemical reaction is the prearrangement of the constituents in a reactive conformation. Furthermore, he is able to show that by exploiting a strong ionic interaction between two chromophores, a coherent molecular motion can be induced and probed in real-time. This way of using bichromophoric interactions provides a promising strategy for future research on conformational dynamics.
Download or read book Molecular Photodissociation Dynamics written by M. N. R. Ashfold and published by CRC Press. This book was released on 1987 with total page 268 pages. Available in PDF, EPUB and Kindle. Book excerpt: Molecular Photodissociation Dynamics was the first title to be published in this series and provides overviews of selected aspects of the subject. The experimental study of photodissociation has been revolutionized by the ready availability of intense, tunable laser sources, operational over a substantial portion of the electromagnetic spectrum, and with parallel developments in theoretical chemistry has opened the way to detailed theoretical study of the fragmentation dynamics of the excited state. This book will therefore be essential reading for those working in this area.
Download or read book Laser Photoionization Spectroscopy written by V. S. Letokhov and published by Academic Press. This book was released on 1987-02-28 with total page 376 pages. Available in PDF, EPUB and Kindle. Book excerpt: Laser Photoionization Spectroscopy discusses the features and the development of photoionization technique. This book explores the progress in the application of lasers, which improve the characteristics of spectroscopic methods. Organized into 12 chapters, this book starts with an overview of the fundamentals of the method for atoms and molecules. This text then examines the photoionization spectroscopy, which is based on the laser resonant excitation of particles into high-lying quantum states that are easy to detect by ionization. Other chapters explain the various basic schemes of multistep excitation, which can be used for resonance photoionization of molecules. This book discusses as well the different applications of the resonance photoionization technique in atomic and molecular spectroscopy. The final chapter considers the two well-known types of microscopy, namely, wave and corpuscular. This book is a valuable resource for chemists, physicists, analysts, and geochemists who are interested in laser spectroscopy techniques to solve nontrivial problems.
Download or read book Electron Molecule Scattering and Photoionization written by P.G. Burke and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 275 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume contains the invited papers and selected contributed papers presented at the International Symposium on 'Electron-Molecule Scattering and Photoionization' held at SERC's Daresbury Laboratory, Cheshire, England from 18th to 19th July, 1987. This Symposium was a Satellite Meeting to the XVth International Conference on the Physics of Electronic and Atomic Collisions (ICPEAC I and follows a tradition of Satellite Meetings i. n related areas of collisions held in association with previous ICPEAC's. In order to make this volume as representative of the Symposium as possible 'Hot Topics' presented orally at the meeting together with a few papers selected by the Programme Committee from the contributed posters are included. The Editors are grateful to the authors for responding rapidly to the invitation to submit their contri butions for inclusion in the volume, as indeed they are grateful to all the authors for the high quality of their contributions. The Symposium brought together over 100 scientists from many countries and from broad interdisciplinary backgrounds to hear about current rapid advances in electron-molecule scatteri. ng and photoioniza tion. These advances have been stimulated on the experimental side by the increasing availability of electron beams with millivolt energy resolution, by synchrotron radiation sources and by intense tunable lasers. On the theoretical side the introduction of new computational methods enables accurate predictions to be made, resulting in a new and deeper understanding of the basic physical processes involved.
Download or read book Nonlinear Laser Spectroscopy written by V. S. Letokhov and published by Springer. This book was released on 2014-04-18 with total page 466 pages. Available in PDF, EPUB and Kindle. Book excerpt: The laser as a source of coherent optical radiation has made it possible to investigate nonlinear interaction of optical radiation with atoms and mole cules. Its availability has given rise to new research fields, such as non linear optics, laser spectroscopy, laser photochemistry, that lie at the boundary between quantum electronics and physical optics, optical spectros copy and photochemistry, respectively. The use of coherent optical radiation in each of these fields has led to the discovery of qualitatively ne\~ effects and possibilities; in particular, some rather subtle effects of interaction between highly monochromatic light and atoms and molecules, in optical spec troscopy, have formed the bases for certain methods of so-called nonlinear, laser Doppler-free spectroscopy. These methods have made it possible to in 5 6 crease the resolution of spectroscopic studies from between 10 and 10 , lim 11 ited by Doppl er 1 i ne broadeni ng up, to about 10 ; at present some 1 abor atories are developing new techniques that have even higher resolution. The discovery and elaboration of the methods of nonlinear laser spectroscopy have resulted largely from contributions by scientists from many countries, in particular from the USA (Massachusetts Institute of Technology, Stanford Uni versity, National Bureau of Standards in Boulder, Harvard University, etc. ), the USSR (P. N. Levedev Institute of Physics, Institute of Semiconductor Phys ics in Novosibirsk, Institute of Spectroscopy, etc.
Download or read book Atomic Molecular and Optical Physics written by National Research Council and published by National Academies Press. This book was released on 1986-02-01 with total page 201 pages. Available in PDF, EPUB and Kindle. Book excerpt: The goals of atomic, molecular, and optical physics (AMO physics) are to elucidate the fundamental laws of physics, to understand the structure of matter and how matter evolves at the atomic and molecular levels, to understand light in all its manifestations, and to create new techniques and devices. AMO physics provides theoretical and experimental methods and essential data to neighboring areas of science such as chemistry, astrophysics, condensed-matter physics, plasma physics, surface science, biology, and medicine. It contributes to the national security system and to the nation's programs in fusion, directed energy, and materials research. Lasers and advanced technologies such as optical processing and laser isotope separation have been made possible by discoveries in AMO physics, and the research underlies new industries such as fiber-optics communications and laser-assisted manufacturing. These developments are expected to help the nation to maintain its industrial competitiveness and its military strength in the years to come. This report describes the field, characterizes recent advances, and identifies current frontiers of research.
Download or read book Higher Excited States of Polyatomic Molecules V3 written by Melvin Robin and published by Elsevier. This book was released on 2012-12-02 with total page 482 pages. Available in PDF, EPUB and Kindle. Book excerpt: Higher Excited States of Polyatomic Molecules, Volume III focuses on higher electronic excitations in polyatomic molecules, with emphasis on excitations beyond 50,000 cm-1. This book explores the various transitions on the basis of their orbital characteristics. Organized into 22 chapters, this volume begins with an overview of the relationships between spectra of different molecules and between the results of various types of spectroscopy. This book then discusses the higher excited states involving Rydberg excitation. Other chapters explore the higher excited states in all classes of biological, organic, and inorganic molecules. This text further discusses the progress in the area of higher excitations in polyatomic atoms and the technique of multiphoton ionization (MPI) spectroscopy that yields a remarkable amount of spectroscopic information applicable to the vacuum-ultraviolet region. The final chapter deals with the vacuum-ultraviolet spectroscopy of biological materials. Analytical chemists, photochemists, molecular spectroscopists, and researchers will find this book extremely useful.
Download or read book Excited States and Photochemistry of Organic Molecules written by Martin Klessinger and published by VCH Publishers. This book was released on 1995 with total page 576 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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
Download or read book Vacuum Ultraviolet Photoionization and Photodissociation of Molecules and Clusters written by Cheuk-Yiu Ng and published by World Scientific. This book was released on 1991 with total page 590 pages. Available in PDF, EPUB and Kindle. Book excerpt: This monograph reviews the recent progress in vacuum ultraviolet (VUV) photoionization and photodissociation processes. Photoionization, photoelectron, and fluorescence spectroscopic techniques have played an important role in revealing the photoionization and photodissociation dynamics of molecules in the vacuum ultraviolet region and in providing accurate energetic and spectroscopic information of ions as well as neutral molecules. The book represents the first detailed review of major experimental developments in the studies of single vacuum ultraviolet photon ionization and dissociation processes of gaseous molecules and clusters.
Download or read book Coherence Phenomena in Atoms and Molecules in Laser Fields written by Andre D Bandrauk and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 397 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume contains the lectures and communications presented at the NATO Advanced Research Workshop (NATO ARW 900857) which was held May 5-10, 1991 at McMaster University, Hamilton, Ontario, Canada. A scientific commitee made up of P.P. Lambropoulos (USC & Crete), P.8. Corkum (NRC, Ottawa), and H. B. vL. van den Heuvell (FOM, Amsterdam) guided the organizers, A.D. Bandrauk (Sherbrooke) and S.C. Wallace (Toronto) in preparing a programme which would cover the latest advances in the field of atom and molecule laser interactions. Since the last meeting held in July 1987 on "Atomic and Molecular Processes with Short Intense Laser Pulses", NATO ASI vol 1718 (Plenum Press 1988), considerable progress has been made in understanding high intensity effects on atoms and the concomitant coherence effects. After four years, the emphasis is now shifting more to molecules. The present volume represents therefore this trend with four sections covering the main interests of research endeavours in this area: i) Atoms in Intense Laser-Fields ii) Molecules in Intense Laser Fields iii) Atomic Coherences iv) Molecular Coherences The experience developed over the years in multiphoton atomic processes has been very useful and is the main source of our understanding of similar processes in molecules. Thus ATI (above threshold ionization) has been found to occur in molecules as well as a new phenomenon, ATD (above-threshold dissociation). Laser-induced avoided crossings of molecular electronic surfaces is also now entering the current language of high intensity molecular processes.
