Understanding Chemical Reactivity – serie

I would like to present to a wide circle of the readers working in quantum chem- istry and solid-state physics, as ,,*ell as in other fields of many-body physics and its interfaces, this book deyoted to density functional theory written by my colleagues Eugene S. Kryachko and Eduardo Y. Ludena. Their ways to this theory are rather different although basically both of them are quantum chemical. Eugene S. Kryachko came to energy density functional theory from the theory of reduced density matrices, and Eduardo \'. Ludena dewloped earlier the concept of loges in quantum chemistry. Neyertheless, their earlier interests giw the possibility to consolidate and formulate energy density functional theory in a unified and consistent way, in my opinion. Raymond Daudel Paris ACKNOWLEDGMENTS The authors are indebted to Carl Almbladh, Victor Va. Antonchenko, John Avery, Richard F. W. Bader, Ulf \'on Barth, Jean-Louis Calais, A. John Coleman, Jens P. Dahl, Robert Donnelly, Harold Englisch, Robert 1\1. Erdahl, Oswaldo Goscinski, John E. Harriman, Gintas Kamuntavichius, Illja G. Kaplan, Jaime Keller, \'alentin Khart- siev, Toshikatsu Koga, Per-Olov Lo\ydin, T. Tung Nguyen-Dang, Ivan Zh.Petkov, Jerome K. Percus, l\lary Beth Ruskai, John R. Sabin, Zdenek Slanina, \'ladimir Shi- rokov, l\lario V. Stoitsov, Yoram Tal, and \Vaitao Yang, who in one way or another, either through their kind support, help, discussions or valuable comments created the human and intellectual background which made this book possible.

Molecular chirality is one of the fundamental aspects of chemistry. Chirality properties of molecules have implications in a wide variety of subjects, ranging from the basic quantum mechanical properties of simple of a few atoms to molecular optical activity, asymmetric synthesis, systems and the folding pattern of proteins. Chirality, in both the geometrical and the topological sense, has also been the subject of investigations in various branches of mathematics. In particular, new developments in a branch of topology, called knot theory, as well as in various branches of discrete mathematics, have led to a novel perspective on the topological aspects of molecular chirality. Some of the mathematical advances have already found applications to the interpretation of new concepts in theoretical chemistry and mathematical chemistry, as well as to novel synthetic approaches leading to new molecules of exceptional structural properties. Some of the new developments in molecular chirality have been truly fundamental to the theoretical understanding and to the actual practice of many aspects of chemistry. The progress in this field has been very rapid, even accelerating in recent years, and a review appears more than justified. This book offers a selection of subjects covering some of the latest developments. Our primary aim is to clarify some of the basic concepts that are the most prone to misinterpretation and to provide brief introductions to some of those subjects that are expected to have further, important contributions to our understanding of molecular properties and chemical reactivity.

Theoretical developments in the surface physics and chemistry of transition metal compounds can be of paramount importance in catalysis, electronic devices, corrosion etc. In this book, a unified survey of the most important methods in theoretical chemistry applied to reactions and processes that occur on transition metal surfaces is presented together with a discussion of their advantages and limitations. Theoretical modelling of chemisorption, diffusion, desorption, effect of promoters, formation of adsorbed intermediates, surface reconstruction, segregation of impurities etc. are reviewed. This book aims to serve as a source of reference material for researchers as well as a text for graduate students following courses on theoretical and computational chemistry related to catalysis and surface chemistry and physics.

The last decade has witnessed significant advances in the ability to generate short light pulses throughout the optical spectrum. These developments have had a tremendous impact on the field of chemical dynamics. Fundamental questions concerning chemical reactions, once thought to be unaddressable, are now easily studied in real-time experiments. Ultrafast spectroscopies are currently being used to study a variety of fundamental chemical phenomena. This book focuses on some of the experimental and associated theoretical studies of reactions in clusters, liquid and solid media. Many of the advances in our understanding of the fundamental details of chemical reactivity result from the interplay of experiment and theory. This theme is present in many of the chapters, indicating the pervasiveness of a combined approach for eludicating molecular models of chemical reactions. With parallel developments in computer simulation, complex chemical sys­ tems are being studied at a molecular level. The discussions presented in this book recount many areas at the forefront of "ultrafast chemistry". They serve the purpose of both bringing the expert up to date with the work being done in many laboratories as well as introducing those not directly involved in this field to the diverse set of problems that can be studied. I hope that this book conveys the excitement that both I and the other authors in this volume feel about the field of ultrafast chemistry. John D. Simon 1993 1.D. Simon (ed.), Ultrafast Dynamics of Chemical Systems, vii.

Nuclear Magnetic Resonance Probes of Molecular Dynamics describes the theoretical basis and experimental techniques that make modern NMR spectroscopy a powerful and flexible tool for probing molecular dynamics in chemical, physical, and biochemical systems. Individual chapters, written by leaders in the development and application of NMR from around the world, treat systems that range from synthetic polymers, liquid crystals, and catalysts to proteins and oligonucleotides and techniques that include deuterium NMR, magic angle spinning, multidimensional spectroscopy, and magnetic resonance imaging. A combination of elementary and advanced material makes the book a useful introduction to the field for students at the graduate level as well as an important reference for practising NMR spectroscopists.

The progress in computer technology during the last 10-15 years has enabled the performance of ever more precise quantum mechanical calculations related to structure and interactions of chemical compounds. However, the qualitative models relating electronic structure to molecular geometry have not progressed at the same pace. There is a continuing need in chemistry for simple concepts and qualitatively clear pictures that are also quantitatively comparable to ab initio quantum chemical calculations. Topological methods and, more specifically, graph theory as a fixed-point topology, provide in principle a chance to fill this gap. With its more than 100 years of applications to chemistry, graph theory has proven to be of vital importance as the most natural language of chemistry. The explosive development of chemical graph theory during the last 20 years has increasingly overlapped with quantum chemistry. Besides contributing to the solution of various problems in theoretical chemistry, this development indicates that topology is an underlying principle that explains the success of quantum mechanics and goes beyond it, thus promising to bear more fruit in the future.

The concept of macroscopic waves and patterns developing from chemical reaction coupling with diffusion was presented, apparently for the first time, at the Main Meeting of the Deutsche Bunsengesellschaft fur Angewandte Physikalische Chemie, held in Dresden, Germany from May 21 to 24, 1906. Robert Luther, Director of the Physical Chemistry Laboratory in Leipzig, read his paper on the discovery and analysis of propagating reaction-diffusion fronts in autocatalytic chemical reactions [1, 2]. He presented an equation for the velocity of these new waves, V = a(KDC)1/2, and asserted that they might have features in common with propagating action potentials in nerve cell axons. During the discussion period, a skeptic in the audience voiced his objections to this notion. It was none other than the great physical chemist Walther Nernst, who believed that nerve impulse propagation was far too rapid to be akin to the propagating fronts. He was also not willing to accept Luther's wave velocity equation without a derivation. Luther stood his ground, saying his equation was "a simple consequence of the corresponding differential equation. " He described several different autocatalytic reactions that exhibit propagating fronts (recommending gelling the solution to prevent convection) and even presented a demonstration: the autocatalytic permanganate oxidation of oxalate was carried out in a test tube with the image of the front projected onto a screen for the audience.

The theme of 'escape from metastable states', either via noise-assisted hop- ping and/or quantum tunneling, is pivotal to many scientific disciplines. It impacts on suchdiversephysical,chemicalandbiologicalprocessesasdiffu- sion in solids, chemical reactions per se, nucleation phenomenaand transfer ofmatter and information in biologicalcomplexes, to name only a few. With 'New Trends in Kramers' Reaction Rate Theory' this book fills yet another part of the multifaceted scope which underpins the Understanding of Chemical Reactivity. Since the publication of the comprehensive review about reaction rate theory in Rev. Mod. Phys. 52, 251 (1990) the field has witnessed many majordevelopments and extensions both in experiment and theory. In this book the focus will be on the theoretical progress. In doing so, the editorscollected aseries ofauthoritative articles from majorpractitioners in the field which as a whole give a representative- although notcomplete- sample ofthe novel recenttheoretical advances. As an inevitable consequence, the editors recognize that not all readers will wish to digest the volume in its entirety.We trust, however, that the reader will be able to choose from the many methods and techniques which he is interested in, and which he requires to perform his own new research in this area. There is the consistent underlying theme of noise-assisted barrier crossing that is running through all of the book. Nevertheless, each chapter should be considered as self contained. In this spirit the editors share the confident beliefthat the future research on the Kramers problem, and related topics, will be invigorated by the selectedcontributions herein.

Rapid advances are taking place in the application of density functional theory (DFT) to describe complex electronic structures, to accurately treat large systems and to predict physical and chemical properties. Both theoretical content and computational methodology are developing at a pace which offers researchers new opportunities in areas such as quantum chemistry, cluster science, and solid state physics. This volume contains ten contributions by leading scientists in the field and provides an authoritative overview of the most important developments. The book focuses on the following themes: determining adequate approximations for the many-body problem of electronic correlations; how to transform these approximations into computational algorithms; applications to discover and predict properties of electronic systems; and developing the theory. This text should be useful for researchers in surface chemistry, catalysis, ceramics and inorganic chemistry.

The principal focus of this volume is to illustrate the level of accuracy currently achievable by "ab initio" quantum chemical calculations. While new developments in theory are discussed to some extent, the major emphasis is on a comparison of calculated properties with experiments. This focus is similar to the one taken in the book, "Comparison of Ab Initio Quantum Chemistry with Experiment for Small Molecules", edited by Rodney Bartlett (Reidel, 1984). However, the phenomenal improvement in both theoretical methods and computer architecture have made it possible to obtain accurate results for rather large molecular systems. For example, the electronic spectra of the nucleic acid base monomer structures shown on the front cover have been obtained using a fully correlated "ab initio" study. This text is intended for researchers, teachers and students in chemistry and physics.

In the study of various phenomena in nature, the concept of similarity plays a fundamental role. Chemistry is no exception; the similarity of molecules, both in their physical properties and in their chemical reactions, provides a basis for their classification, characterization, and scientific description. Ultimately, the recognition and analysis of molecular similarities serve as the basis of an understanding of molecular structures and properties, and rep­ resent the first steps in the development of theoretical models explaining chemical behavior. In this role, molecular similarity is the foundation of predictive models in chemistry. Molecular similarity and molecular reactivity are strongly related. Studying the reactivities of molecules is an important tool for detecting molecular similarities and differences; alternatively, similar molecular properties often imply similar reactivities. This latter aspect is of special value, allowing chemists to make predictions concerning the outcomes of chemical reactions based on molecular similarities. In this book, the central theme, molecular similarity, is discussed from a variety of viewpoints covering the range from rigorous quantum chemical approaches to phenomenological observations expressed within appropriate physical and mathematical frameworks. The authors of the various chapters represent some of the most current fields of research on molecular similarity. It is the hope of the editor that by bringing these subjects together under the cover of this book will provide the readers with a broad perspective and a handy reference of the contemporary approaches to similarity analysis of molecules and reactions.

The reaction pathway (RP) technique is a powerful tool in theoretical chemistry and chemical reaction theory. The present book discusses the background of the concept, both mathematical and physical, and outlines new developments. Different approaches to the RP are described, with particular emphasis on gradient extremals and the treatment of zero eigenvalues of rotation in the Cartesian Hessian matrix along the RP. There is also a review of geometric optimization methods, together with an outline of density functional theory. Some contributions reveal the progress made in interface dynamics calculations based on RP potentials and tunnelling with electronic structure theory ("direct dynamics"). The study also includes the latest results in excited-state RP calculations (H transfer) and a theoretical view of the RPs of photodissociation processes using time-resolved femtosecond spectroscopy. The passage from the RP to the reaction mechanism is described by means of fundamental groups and symmetry rules.

This book gathers original contributions from a selected group of distinguished researchers that are actively working in the theory and practical applications of solvent effects and chemical reactions. The importance of getting a good understanding of surrounding media effects on chemical reacting system is difficult to overestimate. Applications go from condensed phase chemistry, biochemical reactions in vitro to biological systems in vivo. Catalysis is a phenomenon produced by a particular system interacting with the reacting subsystem. The result may be an increment of the chemical rate or sometimes a decreased one. At the bottom, catalytic sources can be characterized as a special kind of surrounding medium effect. The materials involving in catalysis may range from inorganic components as in zeolites, homogenous components, enzymes, catalytic antibodies, and ceramic materials. . With the enormous progress achieved by computing technology, an increasing number of models and phenomenological approaches are being used to describe the effects of a given surrounding medium on the electronic properties of selected subsystem. A number of quantum chemical methods and programs, currently applied to calculate in vacuum systems, have been supplemented with a variety of model representations. With the increasing number of methodologies applied to this important field, it is becoming more and more difficult for non-specialist to cope with theoretical developments and extended applications. For this and other reasons, it is was deemed timely to produce a book where methodology and applications were analyzed and reviewed by leading experts in the field.

The electron density of a non-degenerate ground state system determines essentially all physical properties of the system. This statement of the Hohenberg–Kohn theorem of Density Functional Theory plays an exceptionally important role among all the fundamental relations of Molecular Physics. In particular, the electron density distribution and the dynamic properties of this density determine both the local and global reactivities of molecules. High resolution experimental electron densities are increasingly becoming available for more and more molecules, including macromolecules such as proteins. Furthermore, many of the early difficulties with the determination of electron densities in the vicinity of light nuclei have been overcome. These electron densities provide detailed information that gives important insight into the fundamentals of molecular structure and a better understanding of chemical reactions. The results of electron density analysis are used in a variety of applied fields, such as pharmaceutical drug discovery and biotechnology. If the functional form of a molecular electron density is known, then various molecular properties affecting reactivity can be determined by quantum chemical computational techniques or alternative approximate methods.

The electron density of a non-degenerate ground state system determines essentially all physical properties of the system. This statement of the Hohenberg–Kohn theorem of Density Functional Theory plays an exceptionally important role among all the fundamental relations of Molecular Physics. In particular, the electron density distribution and the dynamic properties of this density determine both the local and global reactivities of molecules. High resolution experimental electron densities are increasingly becoming available for more and more molecules, including macromolecules such as proteins. Furthermore, many of the early difficulties with the determination of electron densities in the vicinity of light nuclei have been overcome. These electron densities provide detailed information that gives important insight into the fundamentals of molecular structure and a better understanding of chemical reactions. The results of electron density analysis are used in a variety of applied fields, such as pharmaceutical drug discovery and biotechnology. If the functional form of a molecular electron density is known, then various molecular properties affecting reactivity can be determined by quantum chemical computational techniques or alternative approximate methods.

The aim of this volume is to offer a balanced overview of molecular Rydberg spectroscopy as it has developed over recent decades. Recent evolution has split Rydberg spectroscopy into two apparently distinct fields: the one concerns the low (n=3-5) Rydberg states, the other the very high (typically n>150) Rydberg states. The former is aimed at spectral levels where Rydberg, valence-shell, and intermediate-type states interact, with a variety of photochemical consequences. The latter considers states extremely close to the ionization limit, from whereionization is possible with a very slight amount of additional energy. Recently developed techniques make it possible to produce ions in well-defined electronic, vibrational and rotational states, including states resulting from spin-orbit or Jahn-Teller splitting. It is then possible to study the structure and reactions of such state-selected ions as well as those of the corresponding neutral molecules. These techniques amount to badly needed high resolution photoelectron spectroscopy.

A quantitative description of the action of enzymes and other biological systems is both a challenge and a fundamental requirement for further progress in our und- standing of biochemical processes. This can help in practical design of new drugs and in the development of artificial enzymes as well as in fundamental understanding of the factors that control the activity of biological systems. Structural and biochemical st- ies have yielded major insights about the action of biological molecules and the mechanism of enzymatic reactions. However it is not entirely clear how to use this - portant information in a consistent and quantitative analysis of the factors that are - sponsible for rate acceleration in enzyme active sites. The problem is associated with the fact that reaction rates are determined by energetics (i. e. activation energies) and the available experimental methods by themselves cannot provide a correlation - tween structure and energy. Even mutations of specific active site residues, which are extremely useful, cannot tell us about the totality of the interaction between the active site and the substrate. In fact, short of inventing experiments that allow one to measure the forces in enzyme active sites it is hard to see how can one use a direct experimental approach to unambiguously correlate the structure and function of enzymes. In fact, in view of the complexity of biological systems it seems that only computers can handle the task of providing a quantitative structure-function correlation.

Entropy and entropy generation play essential roles in our understanding of many diverse phenomena ranging from cosmology to biology. Their importance is manifest in areas of immediate practical interest such as the provision of global energy as well as in others of a more fundamental flavour such as the source of order and complexity in nature. They also form the basis of most modern formulations of both equilibrium and nonequilibrium thermodynamics. Today much progress is being made in our understanding of entropy and entropy generation in both fundamental aspects and application to concrete problems. The purpose of this volume is to present some of these recent and important results in a manner that not only appeals to the entropy specialist but also makes them accessible to the nonspecialist looking for an overview of the field. This book contains fourteen contributions by leading scientists in their fields. The content covers such topics as quantum thermodynamics, nonlinear processes, gravitational and irreversible thermodynamics, the thermodynamics of Taylor dispersion, higher order transport, the mesoscopic theory of liquid crystals, simulated annealing, information and biological aspects, global energy, photovoltaics, heat and mass transport and nonlinear electrochemical systems. Audience: This work will be of value to physicists, chemists, biologists and engineers interested in the theory and applications of entropy and its generation.

This book gathers original contributions from a selected group of distinguished researchers that are actively working in the theory and practical applications of solvent effects and chemical reactions. The importance of getting a good understanding of surrounding media effects on chemical reacting system is difficult to overestimate. Applications go from condensed phase chemistry, biochemical reactions in vitro to biological systems in vivo. Catalysis is a phenomenon produced by a particular system interacting with the reacting subsystem. The result may be an increment of the chemical rate or sometimes a decreased one. At the bottom, catalytic sources can be characterized as a special kind of surrounding medium effect. The materials involving in catalysis may range from inorganic components as in zeolites, homogenous components, enzymes, catalytic antibodies, and ceramic materials. . With the enormous progress achieved by computing technology, an increasing number of models and phenomenological approaches are being used to describe the effects of a given surrounding medium on the electronic properties of selected subsystem. A number of quantum chemical methods and programs, currently applied to calculate in vacuum systems, have been supplemented with a variety of model representations. With the increasing number of methodologies applied to this important field, it is becoming more and more difficult for non-specialist to cope with theoretical developments and extended applications. For this and other reasons, it is was deemed timely to produce a book where methodology and applications were analyzed and reviewed by leading experts in the field.

For the first time in the history of chemical sciences, theoretical predictions have achieved the level of reliability that allows them to - val experimental measurements in accuracy on a routine basis. Only a decade ago, such a statement would be valid only with severe qualifi- tions as high-level quantum-chemical calculations were feasible only for molecules composed of a few atoms. Improvements in both hardware performance and the level of sophistication of electronic structure me- ods have contributed equally to this impressive progress that has taken place only recently. The contemporary chemist interested in predicting thermochemical properties such as the standard enthalpy of formation has at his disposal a wide selection of theoretical approaches, differing in the range of app- cability, computational cost, and the expected accuracy. Ranging from high-level treatments of electron correlation used in conjunction with extrapolative schemes to semiempirical methods, these approaches have well-known advantages and shortcomings that determine their usefulness in studies of particular types of chemical species. The growing number of published computational schemes and their variants, testing sets, and performance statistics often makes it difficult for a scientist not well versed in the language of quantum theory to identify the method most adequate for his research needs.

Hydrogen bonds represent type of molecular interaction that determines the structure and function of a large variety of molecular systems. The elementary dynamics of hydrogen bonds and related proton transfer reactions, both occurring in the ultra fast time domain between 10-14 and 10-11s, form a research topic of high current interest. In this book addressing scientists and graduate students in physics, chemistry and biology, the ultra fast dynamics of hydrogen bonds and proton transfer in the condensed phase are reviewed by leading scientists, documenting the state of the art in this exciting field from the viewpoint of theory and experiment. The nonequilibrium behavior of hydrogen-bonded liquids and intramolecular hydrogen bonds as well as photo induced hydrogen and proton transfer are covered in 7 chapters, making reference to the most recent literature.

Nuclear Magnetic Resonance Probes of Molecular Dynamics describes the theoretical basis and experimental techniques that make modern NMR spectroscopy a powerful and flexible tool for probing molecular dynamics in chemical, physical, and biochemical systems. Individual chapters, written by leaders in the development and application of NMR from around the world, treat systems that range from synthetic polymers, liquid crystals, and catalysts to proteins and oligonucleotides and techniques that include deuterium NMR, magic angle spinning, multidimensional spectroscopy, and magnetic resonance imaging. A combination of elementary and advanced material makes the book a useful introduction to the field for students at the graduate level as well as an important reference for practising NMR spectroscopists.

Molecular Theory of Solvation presents the recent progress in the statistical mechanics of molecular liquids applied to the most intriguing problems in chemistry today, including chemical reactions, conformational stability of biomolecules, ion hydration, and electrode-solution interface. The continuum model of "solvation" has played a dominant role in describing chemical processes in solution during the last century. This book discards and replaces it completely with molecular theory taking proper account of chemical specificity of solvent. The main machinery employed here is the reference-interaction-site-model (RISM) theory, which is combined with other tools in theoretical chemistry and physics: the ab initio and density functional theories in quantum chemistry, the generalized Langevin theory, and the molecular simulation techniques. This book will be of benefit to graduate students and industrial scientists who are struggling to find a better way of accounting and/or predicting "solvation" properties.

The development of "high-tech" materials in contemporary industries is deeply related to a detailed understanding of specific surface properties of catalysts which make particular reactions possible. But this understanding presupposes that there exists a body of theory capable of explaining situations not easily accessible to experimental methods and of relating experimental findings among themselves and with theoretical constructs. For these reasons, theoretical developments in surface physics and surface chemistry of transition metal compounds have been of paramount importance in promoting progress in catalysis, electronic devices, corrosion, etc. Although a great variety of spectroscopic methods for analyzing solids and surfaces at molecular scale have been introduced in recent years, nevertheless, many questions about the adsorption sites and intermediates, the effect of promoters, the poisoning of active sites, the nature of segregation of impurities, the process of surface reconstruction, the mechanisms of reactions, etc. have remained unanswered simply because of the great complexity of surface phenomena. It is in this sense that quantum mechanical method- combined with experimental data - may shed some light on the microscopic properties of new surface materials.

In the study of various phenomena in nature, the concept of similarity plays a fundamental role. Chemistry is no exception; the similarity of molecules, both in their physical properties and in their chemical reactions, provides a basis for their classification, characterization, and scientific description. Ultimately, the recognition and analysis of molecular similarities serve as the basis of an understanding of molecular structures and properties, and rep­ resent the first steps in the development of theoretical models explaining chemical behavior. In this role, molecular similarity is the foundation of predictive models in chemistry. Molecular similarity and molecular reactivity are strongly related. Studying the reactivities of molecules is an important tool for detecting molecular similarities and differences; alternatively, similar molecular properties often imply similar reactivities. This latter aspect is of special value, allowing chemists to make predictions concerning the outcomes of chemical reactions based on molecular similarities. In this book, the central theme, molecular similarity, is discussed from a variety of viewpoints covering the range from rigorous quantum chemical approaches to phenomenological observations expressed within appropriate physical and mathematical frameworks. The authors of the various chapters represent some of the most current fields of research on molecular similarity. It is the hope of the editor that by bringing these subjects together under the cover of this book will provide the readers with a broad perspective and a handy reference of the contemporary approaches to similarity analysis of molecules and reactions.

The so-called reaction path (RP) with respect to the potential energy or the Gibbs energy ("free enthalpy") is one of the most fundamental concepts in chemistry. It significantly helps to display and visualize the results of the complex microscopic processes forming a chemical reaction. This concept is an implicit component of conventional transition state theory (TST). The model of the reaction path and the TST form a qualitative framework which provides chemists with a better understanding of chemical reactions and stirs their imagination. However, an exact calculation of the RP and its neighbourhood becomes important when the RP is used as a tool for a detailed exploring of reaction mechanisms and particularly when it is used as a basis for reaction rate theories above and beyond TST. The RP is a theoretical instrument that now forms the "theoretical heart" of "direct dynamics". It is particularly useful for the interpretation of reactions in common chemical systems. A suitable definition of the RP of potential energy surfaces is necessary to ensure that the reaction theories based on it will possess sufficiently high quality. Thus, we have to consider three important fields of research: - Analysis of potential energy surfaces and the definition and best calculation of the RPs or - at least - of a number of selected and chemically interesting points on it. - The further development of concrete vers ions of reaction theory beyond TST which are applicable for common chemical systems using the RP concept.

Hydrogen bonds represent type of molecular interaction that determines the structure and function of a large variety of molecular systems. The elementary dynamics of hydrogen bonds and related proton transfer reactions, both occurring in the ultra fast time domain between 10-14 and 10-11s, form a research topic of high current interest. In this book addressing scientists and graduate students in physics, chemistry and biology, the ultra fast dynamics of hydrogen bonds and proton transfer in the condensed phase are reviewed by leading scientists, documenting the state of the art in this exciting field from the viewpoint of theory and experiment. The nonequilibrium behavior of hydrogen-bonded liquids and intramolecular hydrogen bonds as well as photo induced hydrogen and proton transfer are covered in 7 chapters, making reference to the most recent literature.