Relaxation Processes in Molecular Excited States

Relaxation Processes in Molecular Excited States PDF Author: J. Fünfschilling
Publisher: Springer Science & Business Media
ISBN: 9400908636
Category : Science
Languages : en
Pages : 282

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Book Description
Relaxation phenomena of excited molecular states are abundant in all nature. They mediate such key processes as photochemical reactions or even the pathways of ordinary chemical reactions. However, for a long time the main research in electronic relaxation processes was concerned with anorganic solids, in part because of their great technological importance (photography, semiconductors ... ) in part also because these compounds were the "workhorses" of the solid state physicists. In the last 30 years, there was a steadily increasing interest in organic molecular systems, first in molecular crystals and later in all forms of molecular solids (glasses, polymers, membranes, ... ). The present volume combines papers on quite different types of relaxation phenomena: the type of solid studied, the electronic states involved, the physical processes responsible for the relaxations are all different. Nevertheless, after reading this book, a more clear and complete picture of the phenomenon "relaxa tion" emerges that proves that this volume is more than just a collection of individual articles. The volume starts with the paper "Spin-lattice and spin-spin relaxation in photo-excited triplet states in molecular crystals" by Jan Schmidt. Even in these seemingly simple systems of isolated guest molecules in a single crystal host, the relaxation phenomena are quite involved and a very thorough investigation is necessary to find the key relaxation processes. The end of the article provides a bridge to the following paper: it treats interactions of two molecules (dimers), where resonant interactions become important and lead to new, characteristic relaxation processes.

Relaxation Processes in Molecular Excited States

Relaxation Processes in Molecular Excited States PDF Author: J. Fünfschilling
Publisher: Springer Science & Business Media
ISBN: 9400908636
Category : Science
Languages : en
Pages : 282

Get Book Here

Book Description
Relaxation phenomena of excited molecular states are abundant in all nature. They mediate such key processes as photochemical reactions or even the pathways of ordinary chemical reactions. However, for a long time the main research in electronic relaxation processes was concerned with anorganic solids, in part because of their great technological importance (photography, semiconductors ... ) in part also because these compounds were the "workhorses" of the solid state physicists. In the last 30 years, there was a steadily increasing interest in organic molecular systems, first in molecular crystals and later in all forms of molecular solids (glasses, polymers, membranes, ... ). The present volume combines papers on quite different types of relaxation phenomena: the type of solid studied, the electronic states involved, the physical processes responsible for the relaxations are all different. Nevertheless, after reading this book, a more clear and complete picture of the phenomenon "relaxa tion" emerges that proves that this volume is more than just a collection of individual articles. The volume starts with the paper "Spin-lattice and spin-spin relaxation in photo-excited triplet states in molecular crystals" by Jan Schmidt. Even in these seemingly simple systems of isolated guest molecules in a single crystal host, the relaxation phenomena are quite involved and a very thorough investigation is necessary to find the key relaxation processes. The end of the article provides a bridge to the following paper: it treats interactions of two molecules (dimers), where resonant interactions become important and lead to new, characteristic relaxation processes.

Excited States

Excited States PDF Author: Edward C. Lim
Publisher:
ISBN:
Category : Energy levels (Quantum mechanics)
Languages : en
Pages : 368

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Book Description


Radiationless Transitions

Radiationless Transitions PDF Author: Sheng Hsien Lin
Publisher:
ISBN:
Category : Science
Languages : en
Pages : 456

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Book Description


Theoretical Methods in Condensed Phase Chemistry

Theoretical Methods in Condensed Phase Chemistry PDF Author: S.D. Schwartz
Publisher: Springer Science & Business Media
ISBN: 0306469499
Category : Science
Languages : en
Pages : 314

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Book Description
This book is meant to provide a window on the rapidly growing body of theoretical studies of condensed phase chemistry. A brief perusal of physical chemistry journals in the early to mid 1980’s will find a large number of theor- ical papers devoted to 3-body gas phase chemical reaction dynamics. The recent history of theoretical chemistry has seen an explosion of progress in the devel- ment of methods to study similar properties of systems with Avogadro’s number of particles. While the physical properties of condensed phase systems have long been principle targets of statistical mechanics, microscopic dynamic theories that start from detailed interaction potentials and build to first principles predictions of properties are now maturing at an extraordinary rate. The techniques in use range from classical studies of new Generalized Langevin Equations, semicl- sical studies for non-adiabatic chemical reactions in condensed phase, mixed quantum classical studies of biological systems, to fully quantum studies of m- els of condensed phase environments. These techniques have become sufficiently sophisticated, that theoretical prediction of behavior in actual condensed phase environments is now possible. and in some cases, theory is driving development in experiment. The authors and chapters in this book have been chosen to represent a wide variety in the current approaches to the theoretical chemistry of condensed phase systems. I have attempted a number of groupings of the chapters, but the - versity of the work always seems to frustrate entirely consistent grouping.

Organic Photochemistry and Photophysics

Organic Photochemistry and Photophysics PDF Author: V. Ramamurthy
Publisher: CRC Press
ISBN: 1000654303
Category : Science
Languages : en
Pages : 245

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Book Description
Featuring contributions from leading experts, Organic Photochemistry and Photophysics is a unique resource that addresses the organic photochemistry and photophysical behavior in aromatic molecules, thiocarbonyls, selected porphyrins, and metalloporphyrins. The book presents theories pertaining to radiative and radiationless transitions. It

Distance Measurements in Biological Systems by EPR

Distance Measurements in Biological Systems by EPR PDF Author: Lawrence J. Berliner
Publisher: Springer Science & Business Media
ISBN: 0306471094
Category : Medical
Languages : en
Pages : 622

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Book Description
Distance measurements in biological systems by EPR The foundation for understanding function and dynamics of biological systems is knowledge of their structure. Many experimental methodologies are used for determination of structure, each with special utility. Volumes in this series on Biological Magnetic Resonance emphasize the methods that involve magnetic resonance. This volume seeks to provide a critical evaluation of EPR methods for determining the distances between two unpaired electrons. The editors invited the authors to make this a very practical book, with specific numerical examples of how experimental data is worked up to produce a distance estimate, and realistic assessments of uncertainties and of the range of applicability, along with examples of the power of the technique to answer biological problems. The first chapter is an overview, by two of the editors, of EPR methods to determine distances, with a focus on the range of applicability. The next chapter, also by the Batons, reviews what is known about electron spin relaxation times that are needed in estimating distances between spins or in selecting appropriate temperatures for particular experiments. Albert Beth and Eric Hustedt describe the information about spin-spin interaction that one can obtain by simulating CW EPR line shapes of nitroxyl radicals. The information in fluid solution CW EPR spectra of dual-spin labeled proteins is illustrated by Hassane Mchaourab and Eduardo Perozo.

Publications

Publications PDF Author: United States. National Bureau of Standards
Publisher:
ISBN:
Category : Government publications
Languages : en
Pages : 668

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Book Description


Effects of Electric Fields on Structure and Reactivity

Effects of Electric Fields on Structure and Reactivity PDF Author: Sason Shaik
Publisher: Royal Society of Chemistry
ISBN: 1839163046
Category : Science
Languages : en
Pages : 447

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Book Description
Electric-field-mediated chemistry is an emerging topic that is rapidly growing and fanning out in many directions. It involves theoretical and experimental aspects, as well as intense interplay between them, including breakthrough achievements such as the proof-of-principle that a Diels–Alder reaction, which involves two simultaneous C–C bond making events, can be catalysed or inhibited simply by changing the direction of an oriented external-electric field (OEEF). This productive interplay between the theoretical and experimental branches of chemistry is continuing, and gradually defining a new sub-field wherein various sources of electric fields, whether external or built-in and designed, or even surface induced fields (plasmons), are brought to bear on chemical reactions, molecular structures, and nano-systems, leading to control of reactivity, selectivity, chirality, molecular orientations, changes in structure, and in dynamics. Written by leaders in the field, Effects of Electric Fields on Structure and Reactivity is the first book on this exciting topic. Starting with an overview of the theory behind – and demonstrations of the effect of – electric fields on structure and reactivity, this accessible reference work aims to encourage those new to the field to consider harnessing these effects in their own work. Covering applications and recent theoretical developments, it is a useful resource for theoretical chemists and experimentalists alike.

Photoselective Chemistry, Volume 47, Part 1

Photoselective Chemistry, Volume 47, Part 1 PDF Author: Joshua Jortner
Publisher: John Wiley & Sons
ISBN: 0470143134
Category : Science
Languages : en
Pages : 786

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Book Description
The Advances in Chemical Physics series provides the chemical physics and physical chemistry fields with a forum for critical, authoritative evaluations of advances in every area of the discipline. Filled with cutting-edge research reported in a cohesive manner not found elsewhere in the literature, each volume of the Advances in Chemical Physics series serves as the perfect supplement to any advanced graduate class devoted to the study of chemical physics.

Encyclopedia of Spectroscopy and Spectrometry

Encyclopedia of Spectroscopy and Spectrometry PDF Author:
Publisher: Academic Press
ISBN: 0128032251
Category : Science
Languages : en
Pages : 3716

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Book Description
This third edition of the Encyclopedia of Spectroscopy and Spectrometry, Three Volume Set provides authoritative and comprehensive coverage of all aspects of spectroscopy and closely related subjects that use the same fundamental principles, including mass spectrometry, imaging techniques and applications. It includes the history, theoretical background, details of instrumentation and technology, and current applications of the key areas of spectroscopy. The new edition will include over 80 new articles across the field. These will complement those from the previous edition, which have been brought up-to-date to reflect the latest trends in the field. Coverage in the third edition includes: Atomic spectroscopy Electronic spectroscopy Fundamentals in spectroscopy High-Energy spectroscopy Magnetic resonance Mass spectrometry Spatially-resolved spectroscopic analysis Vibrational, rotational and Raman spectroscopies The new edition is aimed at professional scientists seeking to familiarize themselves with particular topics quickly and easily. This major reference work continues to be clear and accessible and focus on the fundamental principles, techniques and applications of spectroscopy and spectrometry. Incorporates more than 150 color figures, 5,000 references, and 300 articles for a thorough examination of the field Highlights new research and promotes innovation in applied areas ranging from food science and forensics to biomedicine and health Presents a one-stop resource for quick access to answers and an in-depth examination of topics in the spectroscopy and spectrometry arenas