"Carbon Bonding and Structures: Advances in Physics and Chemistry" features detailed reviews which describe the latest advances in the modeling and characterization of fundamental carbon based materials and recently designed carbon composites. Significant advances are reported and reviewed by globally recognized experts in the field. The quantification, indexing, and interpretation of physical and chemical patterns of carbon atoms in molecules, crystals, and nanosystems is presented. "Carbon Bonding and Structures: Advances in Physics and Chemistry" will be primarily of interest to theoretical physical chemists and computational materials scientists based in academia, government laboratories, and industry.
"Carbon Bonding and Structures: Advances in Physics and Chemistry" features detailed reviews which describe the latest advances in the modeling and characterization of fundamental carbon based materials and recently designed carbon composites. Significant advances are reported and reviewed by globally recognized experts in the field. The quantification, indexing, and interpretation of physical and chemical patterns of carbon atoms in molecules, crystals, and nanosystems is presented. "Carbon Bonding and Structures: Advances in Physics and Chemistry" will be primarily of interest to theoretical physical chemists and computational materials scientists based in academia, government laboratories, and industry.
The search for life in the solar system and beyond has to date been governed by a model based on what we know about life on Earth (terran life). Most of NASA's mission planning is focused on locations where liquid water is possible and emphasizes searches for structures that resemble cells in terran organisms. It is possible, however, that life exists that is based on chemical reactions that do not involve carbon compounds, that occurs in solvents other than water, or that involves oxidation-reduction reactions without oxygen gas. To assist NASA incorporate this possibility in its efforts to search for life, the NRC was asked to carry out a study to evaluate whether nonstandard biochemistry might support life in solar system and conceivable extrasolar environments, and to define areas to guide research in this area. This book presents an exploration of a limited set of hypothetical chemistries of life, a review of current knowledge concerning key questions or hypotheses about nonterran life, and suggestions for future research.
There are more than 20 million chemicals in the literature, with new materials being synthesized each week. Most of these molecules are stable, and the 3-dimensional arrangement of the atoms in the molecules, in the various solids may be determined by routine x-ray crystallography. When this is done, it is found that this vast range of molecules, with varying sizes and shapes can be accommodated by only a handful of solid structures. This limited number of architectures for the packing of molecules of all shapes and sizes, to maximize attractive intermolecular forces and minimizing repulsive intermolecular forces, allows us to develop simple models of what holds the molecules together in the solid. In this volume we look at the origin of the molecular architecture of crystals; a topic that is becoming increasingly important and is often termed, crystal engineering. Such studies are a means of predicting crystal structures, and of designing crystals with particular properties by manipulating the structure and interaction of large molecules. That is, creating new crystal architectures with desired physical characteristics in which the molecules pack together in particular architectures; a subject of particular interest to the pharmaceutical industry.
Biology for AP® courses covers the scope and sequence requirements of a typical two-semester Advanced Placement® biology course. The text provides comprehensive coverage of foundational research and core biology concepts through an evolutionary lens. Biology for AP® Courses was designed to meet and exceed the requirements of the College Board’s AP® Biology framework while allowing significant flexibility for instructors. Each section of the book includes an introduction based on the AP® curriculum and includes rich features that engage students in scientific practice and AP® test preparation; it also highlights careers and research opportunities in biological sciences.
Hydrogen bond (H-bond) effects are known: it makes sea water liquid, joins cellulose microfibrils in trees, shapes DNA into genes and polypeptide chains into wool, hair, muscles or enzymes. Its true nature is less known and we may still wonder why O-H...O bond energies range from less than 1 to more than 30 kcal/mol without apparent reason. This H-bond puzzle is re-examined here from its very beginning and presented as an inclusive compilation of experimental H-bond energies and geometries. New concepts emerge from this analysis: new classes of systematically strong H-bonds (CAHBs and RAHBs: charge- and resonance-assisted H-bonds); full H-bond classification in six classes (the six chemical leitmotifs); and assessment of the covalent nature of strong H-bonds. This leads to three distinct but inter-consistent models able to rationalize the H-bond and predict its strength, based on classical VB theory, matching of donor-acceptor acid-base parameters (PA or pKa), or shape of the H-bond proton-transfer pathway. Applications survey a number of systems where strong H-bonds play an important functional role, namely drug-receptor binding, enzymatic catalysis, ion-transport through cell membranes, crystal design and molecular mechanisms of functional materials.
Chemistry 2e is designed to meet the scope and sequence requirements of the two-semester general chemistry course. The textbook provides an important opportunity for students to learn the core concepts of chemistry and understand how those concepts apply to their lives and the world around them. The book also includes a number of innovative features, including interactive exercises and real-world applications, designed to enhance student learning. The second edition has been revised to incorporate clearer, more current, and more dynamic explanations, while maintaining the same organization as the first edition. Substantial improvements have been made in the figures, illustrations, and example exercises that support the text narrative. Changes made in Chemistry 2e are described in the preface to help instructors transition to the second edition.
Chemical bond stands as the alpha-and-omega of Chemistry: it is at the beginning because, according with International Union of Pure and Applied Chemistry-IUPAC, a bond exists between two atoms or groups of atoms when the forces acting between them lead to an aggregation with sufficient stability to be considered as molecular species; it is also at the end due its mysterious way of acting through electronic behavior that is comparable with nothing of the observed world. The fact that two electrons, which in principle repel each other as they approach, can exist in a certain molecular space providing the atoms-in-molecule binding - that is still an unfolded reality. Nevertheless, quantum theory had furnished the main analytical tools with which the so called ordinary chemistry reduced at the many-electronic problem, a field equally belonging to quantum physics and quantum chemistry. After the impressive success of quantum theory in explaining atomic structure and spectra starting from the complete analytical solution of Hydrogen atom, and after the further quantum extensions of models to include the elucidation of simple molecules, the Chemistry arrives today in front of new challenges: nano- and bio-systems. At this point it seems that there is no chance to provide fully analytical results with the myriads of electrons in macro-molecules. Moreover, even one could admit that the computational techniques will evolve sufficient to deliver numerical results these will certainly suffer of opacity in interpretation loosing the most beloved issue of chemists: the intuition. At the same time, there are also relatively small molecules with particular bonding features, since bonds in which there are no shared electrons between atoms - at one extreme - or molecules with a sextuple bond - at other extreme - may be identified. As a consequence, the increased need of molecular design for assessing nano- and bio- targets through active ligands, the practical demands of predictions of acute toxicity in medicine and ecotoxicology - all these actual realities of chemistry in its principles and applications, call for dedicated reviews. In such theoretically demanded context of conceptual and computational chemistry the present review book likes to give a survey of the quantum physical chemistry and of its application in chemical bond and bonding description. Through the chapters of this book ones of the leading scientists in both physical and chemical fields have gave their valuable contributions for decrypting the actual status quo of the chemical bond and bonding: from self-consistent equations of many-electronic systems, localization, and reactivity principles, to coherent electronic states, to non-covalent bonding and overlapping concepts, to hydrogen and biomolecular bonding, to molecular connectivity and topological indices, to oscillatory quantum states of molecules, to carbon and pseudohalide bonding, to three-center bonding problem, to biochemistry, to medicine, and to ecotoxicology chemical bonding implications. It is therefore a comprehensive volume of physical and chemical quantum approaches of molecules grasping various conceptual and computational levels. It is also an invitation to reflect upon the possibility of unifying the physical and chemical quantum concepts in a novel alchemy of molecular structure. In this respect worth, finally, recalling that the author of Philosophia Naturalis Principia Mathematica was, at his time, proudly considered himself merely as an alchemist, and that his corpuscular vision about light was based on revealed concept of sympathy . From sympathy to bond and bonding it appears that the actual Chemistry and Physics continue to offer fascinating mysteries to humankind of which the elucidation of the nature of the chemical bond being, perhaps, the greatest one.
Class-tested and thoughtfully designed for student engagement, Principles of Organic Chemistry provides the tools and foundations needed by students in a short course or one-semester class on the subject. This book does not dilute the material or rely on rote memorization. Rather, it focuses on the underlying principles in order to make accessible the science that underpins so much of our day-to-day lives, as well as present further study and practice in medical and scientific fields. This book provides context and structure for learning the fundamental principles of organic chemistry, enabling the reader to proceed from simple to complex examples in a systematic and logical way. Utilizing clear and consistently colored figures, Principles of Organic Chemistry begins by exploring the step-by-step processes (or mechanisms) by which reactions occur to create molecular structures. It then describes some of the many ways these reactions make new compounds, examined by functional groups and corresponding common reaction mechanisms. Throughout, this book includes biochemical and pharmaceutical examples with varying degrees of difficulty, with worked answers and without, as well as advanced topics in later chapters for optional coverage. Incorporates valuable and engaging applications of the content to biological and industrial uses Includes a wealth of useful figures and problems to support reader comprehension and study Provides a high quality chapter on stereochemistry as well as advanced topics such as synthetic polymers and spectroscopy for class customization
Chemistry 2e is designed to meet the scope and sequence requirements of the two-semester general chemistry course. The textbook provides an important opportunity for students to learn the core concepts of chemistry and understand how those concepts apply to their lives and the world around them. The book also includes a number of innovative features, including interactive exercises and real-world applications, designed to enhance student learning. The second edition has been revised to incorporate clearer, more current, and more dynamic explanations, while maintaining the same organization as the first edition. Substantial improvements have been made in the figures, illustrations, and example exercises that support the text narrative. Changes made in Chemistry 2e are described in the preface to help instructors transition to the second edition.
