Molecular Interactions

A modern, comprehensive text and reference describing intermolecular forces, this book begins with coverage of the concepts and methods for simpler systems, then moves on to more advanced subjects for complex systems – emphasizing concepts and methods used in calculations with realistic models and compared with empirical data. Contains applications to many physical systems and worked examples Proceeds from introductory material to advanced modern treatments Has relevance for new materials, biological phenomena, and energy and fuels production

The study of gases, clusters, liquids, and solids as units or systems, eventually focuses on the properties of these systems as governed by interactions between atoms, molecules, and radicals that are not covalently bonded to one another. The stereo/spatial properties of molecular species themselves are similarly controlled, with such interactions found throughout biological, polymeric, and cluster systems and are a central feature of chemical reactions. Nevertheless, these interactions are poorly described and characterized, with efforts to do so, usually based on a particular quantum or even classical mechanical procedure, obscuring the fundamental nature of the interactions in the process. Intra- and Intermolecular Interactions Between Noncovalently Bonded Species addresses this issue directly, defining the nature of the interactions and discussing how they should and should not be described. It reviews both theoretical developments and experimental procedures in order to explore interactions between nonbonded entities in such a fundamental manner as to elucidate their nature and origins. Drawing attention to the extensive experience of its editor and team of expert authors, Intra- and Intermolecular Interactions Between Noncovalently Bonded Species is an indispensable guide to the foundational knowledge, latest advances, most pressing challenges, and future directions for all those whose work is influenced by these interactions. Comprehensively describes the nature of interactions between nonbonded species in biological systems, liquids, crystals, clusters, and in particular, water. Combines fundamental, theoretical, background information based on various approximations with the knowledge of experimental techniques. Outlines interactions clearly and consistently with a particular focus on frequency and time-resolved spectroscopies as applied to these 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 summarizes the application of plant derived anticancer compounds as chemopreventives to treat several cancer types, focusing on the molecular mechanisms of action of phytocompounds and providing an overview of the basic processes at the cellular and molecular level that are involved in the progression of the cancer and can be employed in targeted preventive therapies. In addition, it highlights the development of novel anticancer drugs from plant sources using bioinformatics approaches. The compiled chapter data aids readers understanding of issues related to bioavailability, toxic effects and mechanisms of action of phytocompounds, and helps them identify the leads and utilize them against various cancer types effectively. Furthermore, it promotes the use of bioinformatics tools in medicinal plants to expedite their use in plant breeding programs to develop molecular markers to distinguish disease subtypes and predicting mutation, which in turn improves cancer diagnosis and prognosis, and to develop new lead compounds computationally. The book provides scientific verifications of plant compounds mechanisms of action against various cancers and offers useful information for students, teachers, and healthcare professionals involved in drug discovery, and clinical and therapeutic research.

The types of forces that are involved in the interactions between molecules vary across a wide spectrum from very strong, as in ion-ion interactions, to the much weaker forces that are involved in van der Waals complexes. This book provides an introduction to the theoretical methods that are used to analyze each sort of force and provide the reader with a guide to the most appropriate method for a given problem. Examples are used to illustrate the points, and the pitfalls that a novice might encounter are outlined. These examples range from very small complexes to much larger systems with biological relevance.

Intermolecular and Surface Forces describes the role of various intermolecular and interparticle forces in determining the properties of simple systems such as gases, liquids and solids, with a special focus on more complex colloidal, polymeric and biological systems. The book provides a thorough foundation in theories and concepts of intermolecular forces, allowing researchers and students to recognize which forces are important in any particular system, as well as how to control these forces. This third edition is expanded into three sections and contains five new chapters over the previous edition. Starts from the basics and builds up to more complex systems Covers all aspects of intermolecular and interparticle forces both at the fundamental and applied levels Multidisciplinary approach: bringing together and unifying phenomena from different fields This new edition has an expanded Part III and new chapters on non-equilibrium (dynamic) interactions, and tribology (friction forces)