Electron Distributions and the Chemical Bond


Book Description

This book represents the proceedings of a symposium held at the Spring 1981 ACS meeting in Atlanta. The symposium brought together Theoretical Chemists, Solid State Physicists, Experimen tal Chemists and Crystallographers. One of its major aims was to increase interaction between these diverse groups which often use very different languages to describe similar concepts. The devel opment of a common language, or at least the acquisition of a multilingual capability, is a necessity if the field is to prosper. Much depends in this field on the interplay between theory and experiment. Accordingly this volume begins with two introduc tory chapters, one theoretical and the other experimental, which contain much of the background material needed for a through under standing of the field. The remaining sections describe a wide variety of applications and illustrate, we believe, the central role of charge densities in the understanding of chemical bonding. We are most indebted to the Divisions of Inorganic and Phy sical Chemistry of the American Chemical Society, which provided the stimulus for the symposium and gave generous financial support. We also gratefully acknowledge financial support from the Special Educational Opportunities Program of the Petroleum Research Fund administered by the American Chemical Society, which made exten sive participation by speakers from abroad possible.







Information Theory of Molecular Systems


Book Description

As well as providing a unified outlook on physics, Information Theory (IT) has numerous applications in chemistry and biology owing to its ability to provide a measure of the entropy/information contained within probability distributions and criteria of their information "distance" (similarity) and independence. Information Theory of Molecular Systems applies standard IT to classical problems in the theory of electronic structure and chemical reactivity. The book starts by introducing the basic concepts of modern electronic structure/reactivity theory based upon the Density Functional Theory (DFT), followed by an outline of the main ideas and techniques of IT, including several illustrative applications to molecular systems. Coverage includes information origins of the chemical bond, unbiased definition of molecular fragments, adequate entropic measures of their internal (intra-fragment) and external (inter-fragment) bond-orders and valence-numbers, descriptors of their chemical reactivity, and information criteria of their similarity and independence. Information Theory of Molecular Systems is recommended to graduate students and researchers interested in fresh ideas in the theory of electronic structure and chemical reactivity.·Provides powerful tools for tackling both classical and new problems in the theory of the molecular electronic structure and chemical reactivity·Introduces basic concepts of the modern electronic structure/reactivity theory based upon the Density Functional Theory (DFT)·Outlines main ideas and techniques of Information Theory




Principles of Biology


Book Description

The Principles of Biology sequence (BI 211, 212 and 213) introduces biology as a scientific discipline for students planning to major in biology and other science disciplines. Laboratories and classroom activities introduce techniques used to study biological processes and provide opportunities for students to develop their ability to conduct research.




Electron Density and Bonding in Crystals


Book Description

Electron Density and Bonding in Crystals: Principles, Theory and X-Ray Diffraction Experiments in Solid State Physics and Chemistry provides a comprehensive, unified account of the use of diffraction techniques to determine the distribution of electrons in crystals. The book discusses theoretical and practical techniques, the application of electron density studies to chemical bonding, and the determination of the physical properties of condensed matter. The book features the authors' own key contributions to the subject as well a thorough, critical summary of the extensive literature on electron density and bonding. Logically organized, coverage ranges from the theoretical and experimental basis of electron density determination to its impact on investigations of the nature of the chemical bond and its uses in determining electromagnetic and optical properties of crystals. The main text is supplemented by appendices that provide clear, concise guidance on aspects such as systems of units, quantum theory of atomic vibrations, atomic orbitals, and creation and annihilation operators. The result is a valuable compendium of modern knowledge on electron density distributions, making this reference a standard for crystallographers, condensed matter physicists, theoretical chemists, and materials scientists.




Concept Development Studies in Chemistry


Book Description

This is an on-line textbook for an Introductory General Chemistry course. Each module develops a central concept in Chemistry from experimental observations and inductive reasoning. This approach complements an interactive or active learning teaching approach. Additional multimedia resources can be found at: http: //cnx.org/content/col10264/1.5




The VSEPR Model of Molecular Geometry


Book Description

Valence Shell Electron Pair Repulsion (VSEPR) theory is a simple technique for predicting the geometry of atomic centers in small molecules and molecular ions. This authoritative reference was written by Istvan Hartiggai and the developer of VSEPR theory, Ronald J. Gillespie. In addition to its value as a text for courses in molecular geometry and chemistry, it constitutes a classic reference for professionals. Starting with coverage of the broader aspects of VSEPR, this volume narrows its focus to a succinct survey of the methods of structural determination. Additional topics include the applications of the VSEPR model and its theoretical basis. Helpful data on molecular geometries, bond lengths, and bond angles appear in tables and other graphics.




Molecular Modeling


Book Description

Written by experienced experts in molecular modeling, this books describes the basics to the extent that is necessary if one wants to be able to reliably judge the results from molecular modeling calculations. Its main objective is the description of the various pitfalls to be avoided. Without unnecessary overhead it leads the reader from simple calculations on small molecules to the modeling of proteins and other relevant biomolecules. A textbook for beginners as well as an invaluable reference for all those dealing with molecular modeling in their daily work!




Applications of Environmental Aquatic Chemistry


Book Description

Professionals and students who come from disciplines other than chemistry need a concise, yet reliable guide that explains key concepts in environmental chemistry, from the fundamental science to the necessary calculations for applying them. Updated and reorganized, Applications of Environmental Aquatic Chemistry: A Practical Guide, Second Editi




Theoretical Models of Chemical Bonding


Book Description

The renowned theoretical physicist Victor F. Weisskopf rightly pointed out that a real understanding of natural phenomena implies a clear distinction between the essential and the peripheral. Only when we reach such an understanding - that is to say when we are able to separate the relevant from the irrelevant, will the phenomena no longer appear complex, but intelectually transparent. This statement, which is generally valid, reflects the very essence ofmodelling in the quantum theory of matter, on the molecular level in particular. Indeed, without theoretical models one would be swamped by too many details embodied in intricate accurate molecular wavefunctions. Further, physically justified simplificqtions enable studies of the otherwise intractable systems and/or phenomena. Finally, a lack of appropriate models would leave myriads of raw experimental data totally unrelated and incomprehensible. The present series ofbooks dwells on the most important models of chemical bonding and on the variety of its manifestations. In this volume the electronic structure and properties of molecules are considered in depth. Particular attention is focused on the nature of intramolecular interactions which in turn are revealed by various types ofmolecular spectroscopy. Emphasis is put on the conceptual and interpretive aspects of the theory in line with the general philosophy adopted in the series.