Download or read book Molecular Symmetry Super Rotation and Semiclassical Motion written by Hanno Schmiedt and published by . This book was released on 2017 with total page 171 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Molecular Symmetry Super Rotation and Semiclassical Motion written by Hanno Schmiedt and published by Springer. This book was released on 2017-08-31 with total page 171 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents a range of fundamentally new approaches to solving problems involving traditional molecular models. Fundamental molecular symmetry is shown to open new avenues for describing molecular dynamics beyond standard perturbation techniques. Traditional concepts used to describe molecular dynamics are based on a few fundamental assumptions, the ball-and-stick picture of molecular structure and the respective perturbative treatment of different kinds of couplings between otherwise separate motions. The book points out the conceptual limits of these models and, by focusing on the most essential idea of theoretical physics, namely symmetry, shows how to overcome those limits by introducing fundamentally new concepts. The book begins with an introduction to molecular symmetry in general, followed by a discussion of nuclear spin symmetry. Here, a new correlation between identical particle exchange and spin angular momentum symmetry of nuclei is exhibited. The central part of the book is the discussion of extremely floppy molecules, which are not describable in the framework of traditional theories. The book introduces a fundamentally new approach to describing the molecular dynamics of these molecules - the super-rotor model, which is based on a five-dimensional symmetry that has never been observed in molecules before. By applying the super-rotor theory to the prototype of floppy molecules, protonated methane, this model can consistently predict the symmetry and energy of low-energy states, which were characterized experimentally only a few years ago. The theoretical predictions agree with the experimental results, which makes the prospect of further developing the super-rotor theory and applying it to other molecules a promising one. In the final section, the book also covers the topic of ultrafast rotations, where usual quantum calculations reach their natural limits. A semi-classical method for determining rotational energies, developed in the early 1990s, is shown to be attachable to quantum calculations of the vibrational states. This new combined method is suitable for efficiently calculating ro-vibrational energies, even for molecular states with large angular momentum.
Download or read book Fundamentals of Molecular Symmetry written by P.R. Bunker and published by CRC Press. This book was released on 2018-10-03 with total page 244 pages. Available in PDF, EPUB and Kindle. Book excerpt: Winner of a 2005 CHOICE Outstanding Academic Book Award Molecular symmetry is an easily applied tool for understanding and predicting many of the properties of molecules. Traditionally, students are taught this subject using point groups derived from the equilibrium geometry of the molecule. Fundamentals of Molecular Symmetry shows how to set up symmetry groups for molecules using the more general idea of energy invariance. It is no more difficult than using molecular geometry and one obtains molecular symmetry groups. The book provides an introductory description of molecular spectroscopy and quantum mechanics as the foundation for understanding how molecular symmetry is defined and used. The approach taken gives a balanced account of using both point groups and molecular symmetry groups. Usually the point group is only useful for isolated, nonrotating molecules, executing small amplitude vibrations, with no tunneling, in isolated electronic states. However, for the chemical physicist or physical chemist who wishes to go beyond these limitations, the molecular symmetry group is almost always required.
Download or read book Symmetry Properties of Molecules written by G. S. Ezra and published by Springer. This book was released on 1982 with total page 226 pages. Available in PDF, EPUB and Kindle. Book excerpt: The aIm of the present article is to give a critical exposition of the theory of the symmetry properties of rigid and nonrigid molecules. Despite the fact that several accounts of the subject, both technical and didactic, are now available, and despite the extensive discussion of nonrigid molecule symmetry that has been going on since the classic papers of Hougen and Longuet-Higgins, there remains a need for a unifying survey of the problem. Previous treatments have tended to emphasize one or the other particular viewpoint at the expense of a broader view. Renewed interest in the details of the symmetry classification of rotation vibration states of highly symmetric (octahedral) molecules has led to a reexam ination of the relation between conventional point group operations and permutations of identical nuclei in rigid molecules, together with a clarification of the fundamental role of the Eckart constraints and associated Eckart frame. As is shown below, analogous insights can also be obtained in the case of nonrigid molecule symmetry, where the Eckart-Sayvetz conditions provide a natural generalization of the Eckart constraints. The importance of particular definitions of the 'molecule-fixed' frame in the theory of molecular symmetry can be better appreciated by examining their dynamical origin. Chapter 1 is therefore devoted to a description of the derivation of the usual Wilson-Howard-Watson form of the molecular Hamiltonian, together with its generalization to nonrigid molecules. Particular attention is given to the intro duction of molecular models and use of the Eckart and Eckart-Sayvetz constraints.
Download or read book Physics Briefs written by and published by . This book was released on 1994 with total page 1256 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Handbook of Molecular Physics and Quantum Chemistry 3 Volume Set written by Stephen Wilson and published by John Wiley & Sons. This book was released on 2003-03-07 with total page 824 pages. Available in PDF, EPUB and Kindle. Book excerpt: Published in three volumes, this comprehensive reference work brings together in a single source for the first time, a detailed presentation of the most important theoretical concepts and methods for the study of molecules and molecular systems. The logical format of the Handbook allows the reader to progress from the foundations of the field to the most important and exciting areas of current research. Edited and written by an outstanding international team, and containing over 100 articles written by more than 50 contributors, it will be invaluable for both the expert researcher and the graduate student or postdoctoral worker active in any of the broad range of fields where these concepts and methods are important. Comprises three themed volumes: * Fundamentals * Molecular Electronic Structure * Molecules in the Physico-Chemical Environment: Spectroscopy, Dynamics and Bulk Properties * Presents detailed articles covering the key topics, presented in a didactic manner * Focuses both on theory and the relation of experiment to theory Volume 1, Fundamentals presents the foundations of molecular physics and quantum chemistry. It consists of 7 parts arranged as follows:- Part 1 Introduction Part 2 Elements of Quantum Mechanics Part 3 Orbital Models for Atomic, Molecular and Crystal Structure Part 4 Symmetry Groups and Molecular Structure Part 5 Second Quantization and Many-Body Methods Part 6 Approximate Separation of Electronic and Nuclear Motion Part 7 Quantum Electrodynamics of Atoms and Molecules The central problem of molecular physics and quantum chemistry is the description of atomic and molecular electronic structure. The development of appropriate models for the description of the effects of electron correlation and of relativity are key components of the analysis. Volume 2, Molecular Electronic Structure, addresses these topics, and consists of 7 parts arranged as follows: Part 1 Approximation methods Part 2 Orbital Models and Generalized Product Functions Part 3 Electron correlation Part 4 Relativistic molecular electronic structure Part 5 Electronic structure of large molecules Part 6 Computational quantum chemistry Part 7 Visualization and interpretation of molecular electronic structure In reality no molecular system exists in isolation. Molecules interact with other atoms and molecules, and with their environment. Volume 3, Molecules in the Physico-Chemical Environment - Spectroscopy, Dynamics and Bulk Properties, consists of 7 parts arranged as follows:- Part 1 Response theory and propagator methods Part 2 Interactions between molecules Part 3 Molecules in different environments Part 4 Molecular Electronic spectra Part 5 Atomic Spectroscopy and Molecular Vibration-Rotation Spectroscopy Part 6 Molecular dynamics and dynamical processes Part 7 Bulk properties
Download or read book Nuclear Science Abstracts written by and published by . This book was released on 1975 with total page 1146 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Handbook of High resolution Spectroscopy written by Martin Quack and published by John Wiley & Sons. This book was released on 2011-09-26 with total page 2236 pages. Available in PDF, EPUB and Kindle. Book excerpt: The field of High-Resolution Spectroscopy has been considerably extended and even redefined in some areas. Combining the knowledge of spectroscopy, laser technology, chemical computation, and experiments, Handbook of High-Resolution Spectroscopy provides a comprehensive survey of the whole field as it presents itself today, with emphasis on the recent developments. This essential handbook for advanced research students, graduate students, and researchers takes a systematic approach through the range of wavelengths and includes the latest advances in experiment and theory that will help and guide future applications. The first comprehensive survey in high-resolution molecular spectroscopy for over 15 years Brings together the knowledge of spectroscopy, laser technology, chemical computation and experiments Brings the reader up-to-date with the many advances that have been made in recent times Takes the reader through the range of wavelengths, covering all possible techniques such as Microwave Spectroscopy, Infrared Spectroscopy, Raman Spectroscopy, VIS, UV and VUV Combines theoretical, computational and experimental aspects Has numerous applications in a wide range of scientific domains Edited by two leaders in this field Provides an overview of rotational, vibration, electronic and photoelectron spectroscopy Volume 1 - Introduction: Fundamentals of Molecular Spectroscopy Volume 2 - High-Resolution Molecular Spectroscopy: Methods and Results Volume 3 - Special Methods & Applications
Download or read book Dynamic NMR Spectroscopy written by and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 220 pages. Available in PDF, EPUB and Kindle. Book excerpt: Since the first successful NMR experiments in 1946 it was well appreciated that dynamic processes play an important role in the NMR spectroscopy of bulk matter [1]. Early theories on the dependence of the relaxation parameters Tl and T2 on the motions of nuclear spins were successful in explaining the dipolar broadening of the NMR signal in solids and the motional narrowing in liquids [2]. With the discovery of chemical shifts and spin-spin couplings another type of dynamical process affect ing the NMR line shape became apparent, the chemical exchange. As a consequence, dynamical NMR studies split into two groups differing not only in the dynamical topics but also in the method of investigation: physical studies of the motion of spins in liquids and solids by measurement of the relaxation times of single resonances and, on the other hand, chemical studies based on band shape analysis of NMR spectra recorded under steady state conditions. The two fields of research lost some of their basic differences with the development of the Fourier transform NMR method [3], which allows the measurement of relaxation times of different resonances at the same time, i. e. the study of differential motional behavior of different parts of mole cules, thus providing a new tool in conformational analyses. For example, informa tion can be obtained by this method on the relative importance of overall motions and internal motions [4].
Download or read book Dissertation Abstracts International written by and published by . This book was released on 2003 with total page 652 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Vibrational rotational Spectroscopy And Molecular Dynamics written by Dusan Papousek and published by World Scientific. This book was released on 1997-10-31 with total page 576 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book reviews the results of vibration-rotational spectroscopy of molecules obtained recently by combining modern computational methods of quantum chemistry with the new techniques of high-resolution rotational and vibration-rotational spectroscopy. It shows for example that the tunneling vibration-rotational spectroscopy of the van der Waals complexes provides a new look at intermolecular forces while the high precision and sensitivity of the submillimeter-wave and Fourier transform microwave spectroscopy make it possible to study complex rotational spectra of molecules in excited vibrational states. New results of high level ab initio quantum chemical computations of vibrational and rotational energy levels and dipole moment functions of unusual molecules will be discussed together with the recent discovery of clustering of energy levels in asymmetric tops. Group theoretical analysis of floppy molecules, especially the tunneling effects in nonrigid molecules, will also be discussed.
Download or read book Energy Research Abstracts written by and published by . This book was released on 1986 with total page 812 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Condensed Matter Field Theory written by Alexander Altland and published by Cambridge University Press. This book was released on 2010-03-11 with total page 785 pages. Available in PDF, EPUB and Kindle. Book excerpt: This primer is aimed at elevating graduate students of condensed matter theory to a level where they can engage in independent research. Topics covered include second quantisation, path and functional field integration, mean-field theory and collective phenomena.
Download or read book Supersymmetry and String Theory written by Michael Dine and published by Cambridge University Press. This book was released on 2007-01-04 with total page 481 pages. Available in PDF, EPUB and Kindle. Book excerpt: The past decade has witnessed dramatic developments in the field of theoretical physics. This book is a comprehensive introduction to these recent developments. It contains a review of the Standard Model, covering non-perturbative topics, and a discussion of grand unified theories and magnetic monopoles. It introduces the basics of supersymmetry and its phenomenology, and includes dynamics, dynamical supersymmetry breaking, and electric-magnetic duality. The book then covers general relativity and the big bang theory, and the basic issues in inflationary cosmologies before discussing the spectra of known string theories and the features of their interactions. The book also includes brief introductions to technicolor, large extra dimensions, and the Randall-Sundrum theory of warped spaces. This will be of great interest to graduates and researchers in the fields of particle theory, string theory, astrophysics and cosmology. The book contains several problems, and password protected solutions will be available to lecturers at www.cambridge.org/9780521858410.
Download or read book The Sand Reckoner of Archimedes written by Sir Thomas Little Heath and published by Library of Alexandria. This book was released on 2020-09-28 with total page 19 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Beauty and Fascination of Science written by Anatoly L. Buchachenko and published by Springer Nature. This book was released on 2020-07-14 with total page 195 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this book, Professor Anatoly Buchachenko gives a brief and informative description of the most striking achievements and discoveries made in the major natural sciences at the turn of the century – in the late twentieth and early twenty-first centuries. The author has a rare ability to describe scientific discoveries so that these achievements and their significance are understandable not only by professionals and scientists of all specialities, but for any reader interested in modern science, its role in the existence of mankind, and its impact on human society. Originally published in Russian, Professor Buchachenko’s book describes the interaction of natural sciences with social ones—philosophy and history—as well as the part played by the human factor in the development of science, especially the role of the great scientists.
Download or read book Mathematical Reviews written by and published by . This book was released on 1994 with total page 868 pages. Available in PDF, EPUB and Kindle. Book excerpt:
