The Donor Acceptor Approach To Molecular Interactions

Recent developments in various areas of chemistry have been decisively influenced by the principles of structure and mechanism and by the ideas of coordination chemistry, in particular by the donor-acceptor approach, A unified view of almost all kinds of molecular forces is provided by quantum mechanics, and for practical purposes have been classified according to model assumptions, namely, dispersion, polarization, electrostatic, and short-range forces. The latter are divided into two- and three-center covalent chemical bonds, metallic bonds, and exchange-repulsion forces. This approach allows statements of principle and systematic analysis. However, quantitative predictions on concrete large systems are virtually impossible, and there are no general rules that account for structural and chemical changes due to intermolecular interactions. Chemists are therefore left with qualitative descriptions in which the changes in electron densities are considered. Such models as the MO theory or the resonance concept unrealistically assume that the nuclei remain in fixed positions. Further difficulties are encountered in the attempted description on the "nature" of the chemical bond, e.g., the forces involved. In order to avoid these difficulties an extension of the donor-acceptor concept, characterized by the comparison between equilibrium structures in different molecular environments, will be presented in this book. In this way, changes in the positions of the nuclei can be taken into account and the question of the nature of the molecular forces is no longer important.

This book documents the proceedings of the Second International Symposium on Acid-Base Interactions: Relevance to Adhesion Science and Technology held in Newark, New Jersey, October 19--21, 1998. Since the first symposium on this topic was held on the occasion of the 75th birthday of Professor Frederick M. Fowkes in 1990, it was deemed opportune and necessary to hold the second symposium on this topic. This symposium was organized with the following objectives in mind: (i) to consolidate the R&D activity carried out since the first symposium, (ii) to provide a forum for discussion of latest research results, (iii) to provide an opportunity for cross-pollination of ideas, (iv) to identify topics where there was discordance of opinion or discrepancy, and (v) to highlight areas which needed intensified R&D activities. The final technical program contained a total of 36 papers by researchers and technologists from academia, industry and other organizations. This book contains a total of 32 papers, which were rigorously peer reviewed and suitably revised before inclusion in this book. The book is divided into three parts as follows: Part 1: Fundamental Aspects of Acid-Base Interactions; Part 2: Characterization of the Acid-Base Properties of Materials; and Part 3: Applications of Acid-Base Interactions. The topics covered include: Surface free energy acid-base theory applied to solid surfaces; Good, van Oss and Chaudhury theory; contact angle measurements and interpretation; acid-base theory of contact angles; acid-base strength of solid surfaces; acid-base interactions at solid surfaces; acid-base interactions at the molecular level; characterization of acid-base properties of a host of materials (polymers, wood, glass, ceramics, silica particles, textile fibers, rocks) by XPS, inverse gas chromatography, immersion calorimetry, contact angle titration, and thin layer wicking; and relevance of acid-base interactions to bioadhesion, microbial adhesion, polymer adhesion, and adhesion in reinforced polymer composites.

This unique text is ingeniously organized by class of compound and by property or reaction type, not group by group or element by element (which requires students to memorize isolated facts).

The Lewis concept of acids and bases is discussed in every general, organic and inorganic chemistry textbook. This is usually just a descriptive treatment, as it is not possible to devise a single numerical scale suitable for all occasions. However quantitative Lewis acid-base chemistry can be developed by compiling reaction-specific basicity scales which can be used in specific branches of chemistry and biochemistry. Lewis Basicity and Affinity Scales: Data and Measurementbrings together for the first time a comprehensive range of Lewis basicity/affinity data in one volume. More than 2400 equilibrium constants of acid-base reactions, 1500 complexation enthalpies, and nearly 2000 infrared and ultraviolet shifts upon complexation are gathered together in 25 thermodynamic and spectroscopic scales of basicity and/or affinity. For each scale, the definition, the method of measurement, an exhaustive database, and a critical discussion are given. All the data have been critically examined; some have been re-measured; literature gaps have been filled by original measurements; and each scale has been made homogeneous. This collection of data will enable experimental chemists to better understand and predict the numerous chemical, physical and biological properties that depend upon Lewis basicity. Chemometricians will be able to apply their methods to the data matrices constructed from this book in order to identify the factors which influence basicity and basicity-dependent properties. In addition, measured experimental basicities and affinities are essential to computational chemists for the validation, calibration and establishment of reliable computational methods for quantifying and explaining intermolecular forces and the chemical bond. Lewis Basicity and Affinity Scales: Data and Measurement is an essential single-source desktop reference for research scientists, engineers, and students in academia, research institutes and industry, in all areas of chemistry from fundamental to applied research. "The book is a noteworthy piece of work and represents a timely and vast accumulation of knowledge regarding Lewis bases that brings together accurate thermodynamic and spectroscopic data on typical reference Lewis acids. As such, it should serve as a useful and general guide to basicity." J. AM. CHEM. SOC. 2011, 133, 642

Building on the pioneering work in supramolecular chemistry from the last 20 years or so, this monograph addresses new and recent approaches to anion coordination chemistry. Synthesis of receptors, biological receptors and metallareceptors, the energetics of anion binding, molecular structures of anion complexes, sensing devices are presented and computational studies addressed to aid with the understanding of the different driving forces responsible for anion complexation. The reader is promised an actual picture of the state of the art for this exciting and constantly evolving field of supramolecular anion coordination chemistry. The topics range from ion channels to selective sensors, making it attractive to all researchers and PhD students with an interest in supramolecular chemistry.

In the 1970s, Density Functional Theory (DFT) was borrowed from physics and adapted to chemistry by a handful of visionaries. Now chemical DFT is a diverse and rapidly growing field, its progress fueled by numerous developing practical descriptors that make DFT as useful as it is vast. With 34 chapters written by 65 eminent scientists from 13 different countries, Chemical Reactivity Theory: A Density Functional View represents the true collaborative spirit and excitement of purpose engendered by the study and use of DFT. This work instructs readers on how concepts from DFT can be used to describe, understand, and predict chemical reactivity. Prior knowledge is not required as early chapters, written by the field’s original pioneers, cover basic ground-state DFT and its extensions to time-dependent systems, excited states, and spin-polarized molecules. While the text is accessible to senior undergraduate or beginning graduate students, experienced researchers are certain to find interesting new insights in the perspectives presented by these seasoned experts. This remarkable one-of-a-kind resource— Provides authoritative accounts on aspects of the theory of chemical reactivity Describes various global reactivity descriptors, such as electronegativity, hardness, and electrophilicity Introduces and analyzes the usefulness of local reactivity descriptors such as Fukui, shape, and electron localization functions Offers an in-depth analysis of how chemical reactivity changes during different physicochemical processes or in the presence of external perturbations The book covers a gamut of related topics such as methods for determining atoms-in-molecules, population analysis, electrostatic potential, molecular quantum similarity, aromaticity, and biological activity. It also discusses the role of reactivity concepts in industrial and other practical applications. Whether you are searching for new products or new research projects, this is the ultimate guide for understanding chemical reactivity.

This book presents a summary of the application and instrumentation of cell electrophoresis. The method of making cell purification and characterization possible according to the cellular negative surface charge density is discussed, and ideas for future developments are explained. The negative electrostatic forces at cell surfaces provide information about cell-cell interaction, blood vessel sealing, cytokine actions, cell transformation, ion transport phenomena, and other biological phenomena. Recalculations of the physical principles of cell electrophoresis reveal possibilities for removing disruptive factors caused by electrical current, heat, and sedimentation. The introduction of computer technology, the performance of simultaneous two-parameter measurements, and the application of cell-friendly but current-inert buffer systems render the method more reliable and efficient.