Atomic Clusters with Unusual Structure, Bonding and Reactivity


Book Description

Atomic Clusters with Unusual Structure, Bonding and Reactivity: Theoretical Approaches, Computational Assessment and Applications reviews the latest computational tools and approaches available for accurately assessing the properties of a cluster, while also highlighting how such clusters can be adapted and utilized for the development of novel materials and applications. Sections provide an introduction to the computational methods used to obtain global minima for clusters and effectively analyze bonds, outline experimental approaches to produce clusters, discuss specific applications, and explore cluster reactivity and usage across a number of fields.Drawing on the knowledge of its expert editors and contributors, this book provides a detailed guide to ascertaining the stability, bonding and properties of atomic clusters. Atomic clusters, which exhibit unusual properties, offer huge potential as building blocks for new materials and novel applications, but understanding their properties, stability and bonding is essential in order to accurately understand, characterize and manipulate them for further use. Searching for the most stable geometry of a given cluster is difficult and becomes even more so for clusters of medium and large sizes, where the number of possible isomers sharply increase, hence this book provides a unique and comprehensive approach to the topic and available techniques and applications. - Introduces readers to the vast structural and bonding diversity that clusters show and reflects on their potential for novel application and material development - Highlights the latest computational methods and theoretical tools available for identification of the most stable isomers and accurate analysis of bonding in the clusters - Focuses on clusters which violate the rules established in traditional chemistry and exhibit unusual structure, bonding and reactivity




Endohedral Fullerenes: Electron Transfer and Spin


Book Description

This book discusses recent progress in endohedral fullerenes – their production and separation techniques, as well as their characterization and properties. Furthermore, the book delves into the all-important issue of stability by investigating electron transfer between the encapsulated metal species and the carbon cage. It also reviews spin-based phenomena caused by the shielding of endohedral spin by the fullerene, and analyzes formation of the spin states by charge transfer as studied by electron spin resonance. Tuning of charge states of endohedral species and of spin states of both the cage and the cluster are explained. Finally, the book considers the recent discovery of magnetism in some endohedral fullerenes, and the potential for quantum computing.




Molecular Symmetry and Spectroscopy


Book Description

Molecular Symmetry and Spectroscopy deals with the use of group theory in quantum mechanics in relation to problems in molecular spectroscopy. It discusses the use of the molecular symmetry group, whose elements consist of permutations of identical nuclei with or without inversion. After reviewing the permutation groups, inversion operation, point groups, and representation of groups, the book describes the use of representations for labeling molecular energy. The text explains an approximate time independent Schrödinger equation for a molecule, as well as the effect of a nuclear permutation or the inversion of E* on such equation. The book also examines the expression for the complete molecular Hamiltonian and the several groups of operations commuting with the Hamiltonian. The energy levels of the Hamiltonian can then be symmetrically labeled by the investigator using the irreducible representations of these groups. The text explains the two techniques to change coordinates in a Schrödinger equation, namely, (1) by using a diatomic molecule in the rovibronic Schrödinger equation, and (2) by a rigid nonlinear polyatomic molecule. The book also explains that using true symmetry, basis symmetry, near symmetry, and near quantum numbers, the investigator can label molecular energy levels. The text can benefit students of molecular spectroscopy, academicians, and investigators of molecular chemistry or quantum mechanics.




Dynamics at Surfaces: Understanding Energy Dissipation and Physicochemical Processes at the Atomic and Molecular Level


Book Description

Energy release to solid interfaces following chemical reactions is ubiquitous in a vast range of phenomena. Energy dissipation and dynamical disorder (surface entropy), surface friction and molecular diffusion control the rates of heterogeneous catalytic reactions, the efficiency of novel technology, lubrication as well as materials growth including self-assembly and nano-structures. Yet we understand little about the underlying nature of these mechanisms. Fundamentally, energy dissipation including interactions with phonons and electron-hole pairs determines the lifetime of molecular vibrations and rotations as well as the decoherence rate of quantum states. These processes form a central point for many aspects in physical chemistry, are embedded in the mechanisms that control surface dynamical processes and are critical factors in catalysis. They are equally relevant for physicochemical processes in the Earth's atmosphere and astrochemistry occurring on cosmic dust grains.




State of The Art of Molecular Electronic Structure Computations: Correlation Methods, Basis Sets and More


Book Description

State of the Art of Molecular Electronic Structure Computations: Correlation Methods, Basis Sets and More, Volume 79 in the Advances in Quantum Chemistry series, presents surveys of current topics in this rapidly developing field that has emerged at the cross section of the historically established areas of mathematics, physics, chemistry and biology. Chapters in this new release include Computing accurate molecular properties in real space using multiresolution analysis, Self-consistent electron-nucleus cusp correction for molecular orbitals, Correlated methods for computational spectroscopy, Potential energy curves for the NaH molecule and its cation with the cock space coupled cluster method, and much more. - Presents surveys of current topics in this rapidly-developing field that has emerged at the cross section of the historically established areas of mathematics, physics, chemistry and biology - Features detailed reviews written by leading international researchers




Spin Dynamics


Book Description

Spin Dynamics: Basics of Nuclear Magnetic Resonance, Second Edition is a comprehensive and modern introduction which focuses on those essential principles and concepts needed for a thorough understanding of the subject, rather than the practical aspects. The quantum theory of nuclear magnets is presented within a strong physical framework, supported by figures. The book assumes only a basic knowledge of complex numbers and matrices, and provides the reader with numerous worked examples and exercises to encourage understanding. With the explicit aim of carefully developing the subject from the beginning, the text starts with coverage of quarks and nucleons and progresses through to a detailed explanation of several important NMR experiments, including NMR imaging, COSY, NOESY and TROSY. Completely revised and updated, the Second Edition features new material on the properties and distributions of isotopes, chemical shift anisotropy and quadrupolar interactions, Pake patterns, spin echoes, slice selection in NMR imaging, and a complete new chapter on the NMR spectroscopy of quadrupolar nuclei. New appendices have been included on Euler angles, and coherence selection by field gradients. As in the first edition, all material is heavily supported by graphics, much of which is new to this edition. Written for undergraduates and postgraduate students taking a first course in NMR spectroscopy and for those needing an up-to-date account of the subject, this multi-disciplinary book will appeal to chemical, physical, material, life, medical, earth and environmental scientists. The detailed physical insights will also make the book of interest for experienced spectroscopists and NMR researchers. • An accessible and carefully written introduction, designed to help students to fully understand this complex and dynamic subject • Takes a multi-disciplinary approach, focusing on basic principles and concepts rather than the more practical aspects • Presents a strong pedagogical approach throughout, with emphasis placed on individual spins to aid understanding • Includes numerous worked examples, problems, further reading and additional notes Praise from the reviews of the First Edition: "This is an excellent book... that many teachers of NMR spectroscopy will cherish... It deserves to be a ‘classic’ among NMR spectroscopy texts." NMR IN BIOMEDICINE "I strongly recommend this book to everyone…it is probably the best modern comprehensive description of the subject." ANGEWANDTE CHEMIE, INTERNATIONAL EDITION




Nanodroplets


Book Description

Nanodroplets, the basis of complex and advanced nanostructures such as quantum rings, quantum dots and quantum dot clusters for future electronic and optoelectronic materials and devices, have attracted the interdisciplinary interest of chemists, physicists and engineers. This book combines experimental and theoretical analyses of nanosized droplets which reveal many attractive properties. Coverage includes nanodroplet synthesis, structure, unique behaviors and their nanofabrication, including chapters on focused ion beam, atomic force microscopy, molecular beam epitaxy and the "vapor-liquid- solid" route. Particular emphasis is given to the behavior of metallic nanodroplets, water nanodroplets and nanodroplets in polymer and metamaterial nanocomposites. The contributions of leading scientists and their research groups will provide readers with deeper insight into the chemical and physical mechanisms, properties, and potential applications of various nanodroplets.




Endofullerenes


Book Description

To the eyes of a chemist, carbon is certainly one of the most fascinating elements of the periodic table. Basically, the electronic structure and atomic size of carbon enables this element to form a variety of bonds with other elements and, most importantly, with other carbon atoms as weIl. These unique features lead to the amazingly complicated molecular structures we encounter e. g. in life sciences and organic chemistry. Of course, the technical importance of carbon is enormou- but I don't want to carry too many coals to Newcastle. Prom the viewpoint of an astrophysicist or chemist, the significance of carbon lies in the fact that it is the most abundant condensable element in space. Born in the interior of stars, and from there expelled into the interstellar medium, it initiates the formation of simple and complex molecules and of nanoscopic grains. These in turn form huge clouds in space - the birthplace of new stars and planetary systems. The decisive role of carbon in interstellar chemistry is widely accepted and the search for more and more families of interstellar carbon-bearing molecules is a topic of ongoing research. The interdisciplinary aspect of carbon also concerns its various solid forms, in which C and the other closed-cage fullerenes are certainly some of the most popular 60 newcomers.




Spectra of Atoms and Molecules


Book Description

Spectra of Atoms and Molecules, 2nd Edition is designed to introduce advanced undergraduates and new graduate students to the vast field of spectroscopy. Of interest to chemists, physicists, astronomers, atmospheric scientists, and engineers, it emphasizes the fundamental principles of spectroscopy with its primary goal being to teach students how to interpret spectra. The book includes a clear presentation of group theory needed for understanding the material and a large number of excellent problems are found at the end of each chapter. In keeping with the visual aspects of the course, the author provides a large number of diagrams and spectra specifically recorded for this book. Topics such as molecular symmetry, matrix representation of groups, quantum mechanics, and group theory are discussed. Analyses are made of atomic, rotational, vibrational, and electronic spectra. Spectra of Atoms and Molecules, 2nd Edition has been updated to include the 1998 revision of physical constants, and conforms more closely to the recommended practice for the use of symbols and units. This new edition has also added material pertaining to line intensities, which can be confusing due to the dozens of different units used to report line and band strengths. Another major change is in author Peter Bernath's discussion of the Raman effect and light scattering, where the standard theoretical treatment is now included. Aimed at new students of spectroscopy regardless of their background, Spectra of Atoms and Molecules will help demystify spectroscopy by showing the necessary steps in a derivation.




Analysis of Environmental Radionuclides


Book Description

The purpose of this book is to present a state of art summary of current knowledge of methods of assessment of radionuclides in the terrestrial and marine environments. It cover the traditional methods of radioactivity measurements such as radiometrics techniques, but also recent developments in the mass spectrometry sector. The book starts with a short preface introducing the subject of the book, summarising content and philosophy of the book, as well as the most important historical achievements. The scientific topics are introduced by description of sampling methods, optimisation of sampling sites and sampling frequency. The recent developments in radiochemical separation methods using chromatography resins for the treatment of actinides, transuranics and other groups of radioelements are also described. No other book is available covering all aspects of environmental radioactivity measurements, although remarkable progress has been made in detection techniques over the last ten years. At present the new methods enable to carry out investigations which were not possible before, either because of lack of sensitivity or because of the fact that they required too large samples.