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.

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The electron density of a nondegenerate 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. Electron densities provide detailed information that gives important insight into the fundamentals of molecular structure and a better understanding of chemical reactions. 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. This book contains a selection of chapters based on papers given at the 12th conference of the Commission of Charge, Spin and Momentum Density of the International Union for Crystallography, held in Waskiesiu, Prince Albert National Park, Canada, on July 27 - August 1, 1997. The choice of topics represents some of the latest advances in the field of electron, spin, and momentum densities and the analysis of these densities with respect to their roles in determining chemical reactivity. This book provides an exciting collection of accounts of the latest advances, and also provides further motivation for new research to address some of the challenging, unsolved problems of the fascinating interrelations between electron, spin, and momentum densities, and the complex subject of chemical reactivity.

Explicitly Correlated Wave Functions in Chemistry and Physics is the first book devoted entirely to explicitly correlated wave functions and their theory and applications in chemistry and molecular and atomic physics. Explicitly correlated wave functions are functions that depend explicitly on interelectronic distance.
The book covers a wide range of methods based on explicitly correlated functions written by leaders in the field, including Kutzelnigg, Jeziorski, Szalewicz, Klopper and Noga. The book begins with a chapter on the theory of electron correlation and then the following three chapters describe different types of functions that can be used to solve the electronic Schrodinger equation for atoms and molecules. The book goes on to discuss the effects that go beyond the Born-Oppenheimer approximation, theory of relativistic effects, solution of the Dirac-Colomb equation, and relativistic correction using ECG functions. The last part of the book reviews applications of EC functions to calculate atomic and molecular properties and to study positronic systems, resonance states of atoms and nuclear dynamics of the hydrogen molecular ion.
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The present status of Density Functional Theory (DFT), which has evolved as the main technique for the study of matter at the atomistic level, is described in this volume. Knowing the behavior of atoms and molecules provides a sure avenue for the design of new materials with specific features and properties in many areas of science and technology. A technique based on purely first principles allowing large savings in time and money greatly benefits the specialist or designer of new materials.

The range of areas where DFT is applied has expanded and continues to do so. Any area where a molecular system is the center of attention can be studied using DFT.The scope of the 22 chapters in this book amply testifies to this.

"Linear-Scaling Techniques in Computational Chemistry and Physics" summarizes recent progresses in linear-scaling techniques and their applications in chemistry and physics. In order to meet the needs of a broad community of chemists and physicists, the book focuses on recent advances that extended the scope of possible exploitations of the theory.

The first chapter provides an overview of the present state of the linear-scaling methodologies and their applications, outlining hot topics in this field, and pointing to expected developments in the near future. This general introduction is then followed by several review chapters written by experts who substantially contributed to recent developments in this field.

The purpose of this book is to review, in a systematic manner, recent developments in linear-scaling methods and their applications in computational chemistry and physics. Great emphasis is put on the theoretical aspects of linear-scaling methods.

This book serves as a handbook for theoreticians, who are involved in the development of new efficient computational methods as well as for scientists, who are using the tools of computational chemistry and physics in their research.

This book presents recent research on Advanced Computing in Industrial Mathematics, which is one of the most prominent interdisciplinary areas, bringing together mathematics, computer science, scientific computations, engineering, physics, chemistry, medicine, etc. Further, the book presents the major tools used in Industrial Mathematics, which are based on mathematical models, and the corresponding computer codes, which are used to perform virtual experiments to obtain new data or to better understand previous experimental findings. The book gathers the peer-reviewed papers presented at the 11th Annual Meeting of the Bulgarian Section of SIAM (BGSIAM), from December 20 to 22, 2016 in Sofia, Bulgaria.

This book presents the basic theory and application of the Monte Carlo method to the electronic structure of atoms and molecules. It assumes no previous knowledge of the subject, only a knowledge of molecular quantum mechanics at the first-year graduate level. A working knowledge of traditional ab initio quantum chemistry is helpful, but not essential.Some distinguishing features of this book are:

This book presents the basic theory and application of the Monte Carlo method to the electronic structure of atoms and molecules. It assumes no previous knowledge of the subject, only a knowledge of molecular quantum mechanics at the first-year graduate level. A working knowledge of traditional ab initio quantum chemistry is helpful, but not essential.Some distinguishing features of this book are:

This book explores the relaxation dynamics of inner-valence-ionized diatomic molecules on the basis of extreme-ultraviolet pump-probe experiments performed at the free-electron laser (FEL) in Hamburg. Firstly, the electron rearrangement dynamics in dissociating multiply charged iodine molecules is studied in an experiment that made it possible to access charge transfer in a thus far unexplored quasimolecular regime relevant for plasma and chemistry applications of the FEL. Secondly the lifetime of an efficient non-radiative relaxation process that occurs in weakly bound systems is measured directly for the first time in a neon dimer (Ne2). Interatomic Coulombic decay (ICD) has been identified as the dominant decay mechanism in inner-valence-ionized or excited van-der-Waals and hydrogen bonded systems, the latter being ubiquitous in all biomolecules. The role of ICD in DNA damage thus demands further investigation, e.g. with regard to applications like radiation therapy.

Quantum Simulations of Materials and Biological Systems features contributions from leading world experts in the fields of density functional theory (DFT) and its applications to material and biological systems. The recent developments of correlation functionals, implementations of Time-dependent algorithm into DFTB+ method are presented. The applications of DFT method to large materials and biological systems such as understanding of optical and electronic properties of nanoparticles, X-ray structure refinement of proteins, the catalytic process of enzymes and photochemistry of phytochromes are detailed. In addition, the book reviews the recent developments of methods for protein design and engineering, as well as ligand-based drug design. Some insightful information about the 2011 International Symposium on Computational Sciences is also provided. Quantum Simulations of Materials and Biological Systems is aimed at faculties and researchers in the fields of computational physics, chemistry and biology, as well as at the biotech and pharmaceutical industries.

Multi-scale Quantum Models for Biocatalysis explores various molecular modelling techniques and their applications in providing an understanding of the detailed mechanisms at play during biocatalysis in enzyme and ribozyme systems. These areas are reviewed by an international team of experts in theoretical, computational chemistry, and biophysics.

This book presents detailed reviews concerning the development of various techniques, including ab initio molecular dynamics, density functional theory, combined QM/MM methods, solvation models, force field methods, and free-energy estimation techniques, as well as successful applications of multi-scale methods in the biocatalysis systems including several protein enzymes and ribozymes.

This book is an excellent source of information for research professionals involved in computational chemistry and physics, material science, nanotechnology, rational drug design and molecular biology and for students exposed to these research areas."

Reinvigorated by advances and insights the quantum theory of irreversible processes has recently attracted growing attention.

This volume introduces the very basic concepts of semigroup dynamics of open quantum systems and reviews a variety of modern applications. Originally published as Volume 286 (1987) in Lecture in Physics, this volume has been newly typeset, revised and corrected and also expanded to include a review on recent developments.

Interest in structures with nanometer-length features has significantly increased as experimental techniques for their fabrication have become possible. The study of phenomena in this area is termed nanoscience, and is a research focus of chemists, pure and applied physics, electrical engineers, and others. The reason for such a focus is the wide range of novel effects that exist at this scale, both of fundamental and practical interest, which often arise from the interaction between metallic nanostructures and light, and range from large electromagnetic field enhancements to extraordinary optical transmission of light through arrays of subwavelength holes. This dissertation is aimed at addressing some of the most fundamental and outstanding question in nanoscience from a theoretical computational perspective, specifically: (i) At the single nanoparticle level, how well do experimental and classical electrodynamics agree? (ii) What is the detailed relationship between optical response and nanoparticle morphology, composition, and environmental? (iii) Does an optimal nanostructure exist for generation large electromagnetic field enhancements, and is there a fundamental limit to this? (iv) Can nanostructures be used to control light, such as confining it, or causing fundamentally different scattering phenomena to interact, such as electromagnetic surface modes and diffraction effects? (v) Is it possible to calculate quantum effects using classical electrodynamics, and if so, how do they affect optical properties?

Structure of Crystals describes the ideal and real atomic structure of crystals as well as the electronic structures. The fundamentals of chemical bonding between atoms are given, and the geometric representations in the theory of crystal structure and crystal chemistry, as well as the lattice energy, are considered. The important classes of crystal structures in inorganic compounds as well as the structures of polymers, liquid crystals, biological crystals, and macromolecules are treated. This edition is complemented with recent data on many types of crystal structures - e.g., the structure of fullerenes, high-temperature superconductors, minerals, and liquid crystals.

This book presents an in-depth study into the utility of -bond metathesis in Group 2 mediated reactivity. A comprehensive introduction defines the state of the art in both Group 2 mediated catalysis and dehydrocoupling. Structural investigations giving rise to a range of mixed s-block metal hydrides including a remarkable dodecabimetallic decahydride are then described. Subsequent extensive mechanistic work focussing on both silicon-nitrogen and boron-nitrogen dehydrocoupling gives insights into both congeneric effects down Group 2 and ligand effects centring upon magnesium. These studies show the striking effects of these factors, as well as the electronic nature of the hydridic coupling partner. Finally, the unprecedented introduction of single-electron transfer steps into Group 2 catalytic manifolds is described. The use of the stable radical TEMPO to induce single-electron transfer to substituents bound to Group 2 centres coupled with -bond metathesis allows a novel hydrogen release from silanes.

The focus of the present work is nonrelativistic and relativistic quantum mechanics with standard applications to the hydrogen atom. The author has aimed at presenting quantum mechanics in a comprehensive yet accessible for mathematicians and other non-physicists. The genesis of quantum mechanics, its applications to basic quantum phenomena, and detailed explanations of the corresponding mathematical methods are presented. The exposition is formalized (whenever possible) on the basis of the coupled Schroedinger, Dirac and Maxwell equations. Aimed at upper graduate and graduate students in mathematical and physical science studies.

In the area of organic chemistry one major challenge we are currently faced with is how to assemble potentially useful molecules in new ways that generate molecular complexity and in sequences that are as efficient as possible. Our efforts in this regard, specifically for the preparation of amino containing compounds incorporating an aromatic ring, are described in this doctoral thesis. We discovered an interesting regioselectivity in an intramolecular Heck reaction, which we studied for a series of substrates that are unbiased in terms of the size of the newly formed ring, where very high levels of selectivity in relation to the new carbon-carbon bond are typically observed. DFT calculations were performed to attempt to shed light on the reaction sequence. This regioselective Heck reaction, combined with the reductive removal of the temporary amino-protecting group, allowed us to synthesize the Sceletium alkaloids: mesembrane, mesembranol and mesembrine.

"Advanced Topics in Theoretical Chemical Physics"" "is a collection of 20 selected papers from the scientific presentations of the Fourth Congress of the International Society for Theoretical Chemical Physics (ISTCP) held at Marly-le-Roi, France, in July 2002.

"Advanced Topics in Theoretical Chemical Physics" encompasses a broad spectrum in which scientists place special emphasis on theoretical methods in chemistry and physics. The chapters in the book are divided into five sections:

I: Advances Chemical Thermodynamics

II: Electronic Structure of Molecular Systems

III: Molecular Interaction and Dynamics

IV: Condensed Matter

V: Playing with Numbers

This book is an invaluable resource for all academics and researchers interested in theoretical, quantum or statistical, chemical physics or physical chemistry. It presents a selection of some of the most advanced methods, results and insights in this exciting area.

"Advanced Topics in Theoretical Chemical Physics" encompasses a broad spectrum in which scientists place special emphasis on theoretical methods in chemistry and physics. The chapters in the book are divided into five sections:

I: Advances Chemical Thermodynamics

II: Electronic Structure of Molecular Systems

III: Molecular Interaction and Dynamics

IV: Condensed Matter

V: Playing with Numbers

This book is an invaluable resource for all academics and researchers interested in theoretical, quantum or statistical, chemical physics or physical chemistry. It presents a selection of some of the most advanced methods, results and insights in this exciting area.

It is difficult to overestimate the impact that density functional theory has had on computational quantum chemistry over the last two decades. Indeed, this period has seen it grow from little more than a theoreticalcuriosity to become a central tool in the computational chemist s armoury. Arguably no area of ch- istry has benefited more from the meteoric rise in density functional theory than inorganic chemistry. the ability to obtainreliable results in feasible ti- scales on systems containing heavy elements such as the d and f transition - tals has led to an enormous growth in computational inorganic chemistry. The inorganic chemical literature reflects this growth; it is almost impossible to open a modern inorganic chemistry journal without finding several papers devoted exclusively or in part to density functional theory calculations. The real imp- tance of the rise in density functional theory in inorganic chemistry is undou- edly the much closer synergy between theory and experiment than was p- viously posible. In these volumes, world-leading researchers describe recent developments in the density functional theory and its applications in modern inorganic and b- inorganic chemistry. These articles address key issues key issues in both sol- state and molecular inorganic chemistry, such as spectroscopy, mechanisms, catalysis, bonding and magnetism. The articles in volume I are more focussed on advances in density functional methodogy, while those in Volume II deal more with applications, although this is by no means a rigid distinction.

These two volumes collect forty-four selected papers from the scientific contributions presented at the Third European Workshop on Quantum Systems in Chemistry and Physics, held in Granada (Spain), April 19-22, 1998. Ninety-nine scientists from Bulgaria, Columbia, Cuba, Denmark, Finland, France, Germany, Hungary, Israel, Italy, Mexico, Netherlands, Norway, Poland, Russia, Slovakia, Spain, Sweden, United Ki- dom, Uruguay and Venezuela attended the workshop, discussing the state of the art, new trends, and future evolution of the methods and applications. The workshop took place at the 'Los Alixares' Hotel, where 45 lectures were given by prominent members of the scientific community; in addition, 49 posters were presented in two very animated sessions. The success of this workshop is due, without doubt, to the excellent tradition initiated at the previous workshops, organised by Prof. R. McWeeny in San Miniato, Pisa (Italy), 1996, and by Prof. S. Wilson in Oxford (United Kingdom), 1997. These workshops create occasions for meetings and disc- sions on the current state of the art, emerging methods and applications and new trends in this area of science. The three meetings were sponsored and partially supported by the European Union (EU) in the frame of the Cooperation in Science and Technology (COST) chemistry actions.

The Twenty Sixth Jerusalem Symposium reflected the high standards of these distinguished scientific meetings, which convene once a year at the Israel Academy of Sciences and Humanities in Jerusalem to discuss a specific topic in the broad area of quantum chemistry and biochemistry. The topic at this year's Jerusalem Symposium was reaction dynamics in clusters and condensed phases, which constitutes a truly interdisciplinary subject of central interest in the areas of chemical dynamics, kinetics, photochemistry and condensed matter chemical physics. The main theme of the Symposium was built around the exploration of the interrelationship between the dynamics in large finite clusters and in infinite bulk systems. The main issues addressed microscopic and macroscopic sol vation phenomena, cluster and bulk spectroscopy, photodissociation and vibrational predissociation, cage effects, interphase dynamics, reaction dynamics and energy transfer in clusters, dense fluids, liquids, solids and biophysical systems. The interdisciplinary nature of this research area was deliberated by intensive and extensive interactions between modern theory and advanced experimental methods. This volume provides a record of the invited lectures at the Symposium.

Heavy atoms and their compounds are important in many areas of modern technology. Their versatility in the reactions they undergo is the reason that they can be found in most homogeneous and heterogeneous catalysts. Their magnetism is the decisive property that qualifies them as materials for modern storage devices.

The phenomena observed in compounds of heavy atoms such as phosphorescence, magnetism or the tendency for high valency in chemical reactions can to a large extent be traced back to relativistic effects in their electronic structure. Thus, in many respects relativistic effects dominate the physics and chemistry of heavy atoms and their compounds.

Chemists are usually aware of these phenomena. However, the theory behind them is not part of the standard chemistry curriculum and thus not widely known among experimentalists. Whilst the relativistic quantum theory of electronic structure is well established in physics, applications of the theory to chemical systems and materials have been feasible only in the last decade and their practical applications in connection with chemical experiment is somewhat out of sight of modern theoretical physics.

Relativistic Effects in Heavy Element Chemistry and Physics intends to bridge the gap between chemistry and physics on the one hand and theory and experiment on the other.

Topics covered include:

- A broad range from quantum electrodynamics to the phenomenology of the compounds of heavy and superheavy elements;

- A state-of-the-art survey of the most important theoretical developments and applications in the field of relativistic effects in heavy-element chemistry and physics in the last decade;

- Special emphasis on the work of researchers in Europe and Germany in the framework of research programmes of the European Science Foundation and the German Science Foundation.