Properties of Chemically Interesting Potential Energy Surfaces


Book Description

Contemporary chemical reaction theory is the characterization of Potential Energy Hypersurfaces (PES). The authors critically analyze chemically and mathematically suitable reaction path definitions. The book presents a simple mathematical analysis of stationary and critical points of the PES. It provides tools for studying chemical reactions by calculating reaction paths and related curves. A further aspect of the book is the dependence of PES properties on approximations used for the analysis. Recent quantum chemical calculations, particularly of single proton transfer processes, and experimental data are compared. The book addresses students and researchers in Theoretical Chemistry, Chemical Kinetics and related fields.




Potential Energy Surfaces and Dynamics Calculations


Book Description

The present volume is concerned with two of the central questions of chemical dynamics. What do we know about the energies of interaction of atoms and molecules with each other and with solid surfaces? How can such interaction energies be used to understand and make quantitative predictions about dynamical processes like scattering, energy transfer, and chemical reactions? It is becoming clearly recognized that the computer is leading to rapid progress in answering these questions. The computer allows probing dynamical mechanisms in fine detail and often allows us to answer questions that cannot be addressed with current experimental techniques. As we enter the 1980's, not only are more powerful and faster computers being used, but techniques and methods have been honed to a state where exciting and reliable data are being generated on a variety of systems at an unprecedented pace. The present volume presents a collection of work that illustrates the capabilities and some of the successes of this kind of computer-assisted research. In a 1978 Chemical Society Report, Frey and Walsh pointed out that "it is extremely doubtful if a calculated energy of activation for any unimolecular decomposition can replace an experimental deter mination. " However they also recorded that they "believe[d] that some of the elaborate calculations being performed at present do suggest that we may be approaching a time when a choice between reaction mechanisms will be helped by such [computational] work.




Potential Energy Surfaces


Book Description

Potential Energy Surfaces is a collection of lectures given at the 1996 Mariapfarr Workshop in Theoretical Chemistry, organized by Alexander F. Sax. The Mariapfarr Workshops' aim is to discuss in-depth topics in Theoretical Chemistry. The target group of these workshops is graduate students and postdocs.




Exploration on Quantum Chemical Potential Energy Surfaces


Book Description

Providing several examples, this book describes fundamental methods and techniques specific for efficient exploration on the potential energy surface by quantum chemical calculations.




Research in Atomic Structure


Book Description

Impressive advances have been made in the study of atomic structures, at both the experimental and theoretical levels. And yet, the scarcity of information on atomic energy levels is evident At the same time there exists a need for data, because of the developments in such diverse fields as astrophysics and plasma and laser research, all of them of fundamental importance as well as practical impact. This project of research in atomic structure, consisting of three components (formulation, computer program, and numerical results), constitutes a basic and comprehensive work with a variety of uses. In its most practical application, it will yield a rather accurate prediction of the energy levels of any atomic system, of use per se or in the interpretation and confirmation of experimental results. On the other hand, it will also be of use in the comparative study of the appropriateness of the various levels of approximation and as a point of reference.




Transport, Relaxation, and Kinetic Processes in Electrolyte Solutions


Book Description

The presence of freely moving charges gives peculiar properties to electrolyte solutions, such as electric conductance, charge transfer, and junction potentials in electrochemical systems. These charges play a dominant role in transport processes, by contrast with classical equilibrium thermodynamics which considers the electrically neutral electrolyte compounds. The present status of transport theory does not permit a first prin ciples analys1s of all transport phenomena with a detailed model of the relevant interactions. Host of the models are still unsufficient for real systems of reasonable complexity. The Liouville equation may be adapted with some Brownian approximations to problems of interact ing solute particles in a continuum (solvent>; however, keeping the Liouville level beyond the limiting laws is an unsolvable task. Some progress was made at the Pokker-Planck level; however, despite a promising start, this theory in its actual form is still unsatis factory for complex systems involving many ions and chemical reac tions. A better approach is provided by the so-called Smoluchowski level in which average velocities are used, but there the hydrodyna mic interactions produce some difficulties. The chemist or chemical engineer, or anyone working with complex electrolyte solutions in applied research wants a general representa tion of the transport phenomena which does not reduce the natural complexity of the multicomponent systems. Reduction of the natural complexity generally is connected with substantial changes of the systems.




Overlap Determinant Method in the Theory of Pericyclic Reactions


Book Description

The author summarizes the development and the applications of overlap determinant method in various fields of pericyclic reactivity. The greatest advantage of this new method lies in its remarkable simplicity and flexibility owing to which it opens an interesting possibility of the systematic investigation of important mechanistic problems of pericyclic reactivity which were so far beyond the scope of other existing techniques.




Evolution of Size Effects in Chemical Dynamics, Volume 70, Part 1


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.




Potential Energy Surfaces


Book Description

Shows the diversity and sophistication of present knowledge of molecular collisions and the forces that govern their outcome, examining major aspects from the point of view of the potential surface. Covers such topics as angle dependent potentials, vibranic coupling, and branching ratios in simple atomic reactions.




Theoretical Models of Chemical Bonding


Book Description

The state-of-the-art in contemporary theoretical chemistry is presented in this 4-volume set with numerous contributions from the most highly regarded experts in their field. It provides a concise introduction and critical evaluation of theoretical approaches in relation to experimental evidence.