Download or read book Geometrical Derivatives of Energy Surfaces and Molecular Properties written by Poul Jørgensen and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 337 pages. Available in PDF, EPUB and Kindle. Book excerpt: The development and computational implementation of analytical expres sions for the low-order derivatives of electronic energy surfaces and other molecular properties has undergone rapid growth in recent years. It is now fairly routine for chemists to make use of energy gradient information in locating and identifying stable geometries and transition states. The use of second analytical derivative (Hessian or curvature) expressions is not yet routine, and third and higher energy derivatives as well as property (e.g., dipole moment, polarizability) derivatives are just beginning to be applied to chemical problems. This NATO Advanced Research Workshop focused on analyzing the re lative merits of various strategies for deriving the requisite analyti cal expressions, for computing necessary integral derivatives and wave function parameter derivatives, and for efficiently coding these expres sions on conventional scalar machines and vector-oriented computers. The participant list contained many scientists who have been instrumen tal in bringing this field to fruition as well as eminent scientists who have broad knowledge and experience in quantum chemistry in general.
Download or read book Molecular Distortions in Ionic and Excited States written by Peter V. Schastnev and published by CRC Press. This book was released on 1995-08-25 with total page 192 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book discusses the achievements in the study on the structure of active species being formed at the change of molecule charge or electronic state. It gives a systematic outline of the problem of molecular structure distortions in radical ionic and excited states involving experimental and theoretical material. The text focuses on analyzing the physical reasons for structural distortion occurrences at a model level and also with results of detailed quantum-chemical calculations. The book presents numerous facts on the structural distortions in ions of various types of organic molecules. Data is presented for the first time on distortions in radical ions of polyfluoroaromatics and other conjugated molecules.
Download or read book Ab Initio Methods in Quantum Chemistry Volume 69 Part 2 written by K. P. Lawley and published by John Wiley & Sons. This book was released on 2009-09-08 with total page 600 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Advances in Chemical Physics series provides the chemical physics and physical chemistry fields with a forum for critical, authoritative evaluations of advances in every area of the discipline. Filled with cutting-edge research reported in a cohesive manner not found elsewhere in the literature, each volume of the Advances in Chemical Physics series serves as the perfect supplement to any advanced graduate class devoted to the study of chemical physics.
Download or read book Advances in Chemical Physics Volume 125 written by Ilya Prigogine and published by John Wiley & Sons. This book was released on 2003-01-31 with total page 605 pages. Available in PDF, EPUB and Kindle. Book excerpt: Advances in Chemical Physics covers recent advances at the cutting edge of research relative to chemical physics. The series, Advances in Chemical Physics, provides a forum for critical, authoritative evaluations of advances in every area of the discipline.
Download or read book Cluster Models for Surface and Bulk Phenomena written by Gianfranco Pacchioni and published by Springer Science & Business Media. This book was released on 2013-03-08 with total page 683 pages. Available in PDF, EPUB and Kindle. Book excerpt: It is widely recognized that an understanding of the physical and chemical properties of clusters will give a great deal of important information relevant to surface and bulk properties of condensed matter. This relevance of clusters for condensed matter is one of the major motivations for the study of atomic and molecular clusters. The changes of properties with cluster size, from small clusters containing only a few atoms to large clusters containing tens of thousands of atoms, provides a unique way to understand and to control the development of bulk properties as separated units are brought together to form an extended system. Another important use of clusters is as theoretical models of surfaces and bulk materials. The electronic wavefunctions for these cluster models have special advantages for understanding, in particular, the local properties of condensed matter. The cluster wavefunctions, obtained with molecular orbital theory, make it possible to relate chemical concepts developed to describe chemical bonds in molecules to the very closely related chemical bonding at the surface and in the bulk of condensed matter. The applications of clusters to phenomena in condensed matter is a cross-disciplinary activity which requires the interaction and collaboration of researchers in traditionally separate areas. For example, it is necessary to bring together workers whose background and expertise is molecular chemistry with those whose background is solid state physics. It is also necessary to bring together experimentalists and theoreticians.
Download or read book Theoretical Chemistry Accounts written by Christopher Cramer and published by Springer Science & Business Media. This book was released on 2013-11-11 with total page 205 pages. Available in PDF, EPUB and Kindle. Book excerpt: For the New Century Issue of the journal "Theroretical Chemistry Accounts" the advisory editors identified papers from the first century of theoretical chemistry and discussed their importance for the twentieth century with an eye towards the twenty-first century. Sixty-six such perspectives are published in the New Century Issue. To make this unique collection available to younger scientists for entertaining reading and re-reading of the original publications, the publisher decided to reprint a special edition of the issue.
Download or read book Novel Electronic Structure Theory General Innovations and Strongly Correlated Systems written by and published by Academic Press. This book was released on 2018-01-03 with total page 376 pages. Available in PDF, EPUB and Kindle. Book excerpt: Novel Electronic Structure Theory: General Innovations and Strongly Correlated Systems, Volume 76, the latest release in the Advances in Quantum Chemistry series presents work and reviews of current work in quantum chemistry (molecules), but also includes scattering from atoms and solid state work of interest in physics. Topics covered in this release include the Present Status of Selected Configuration Interaction with Truncation Energy Error, Recent Developments in Asymptotic Expansions from Numerical Analysis and Approximation Theory, The kinetic energy Pauli enhancement factor and its role in determining the shell structure of atoms and molecules, Numerical Hartree-Fock and Many-Body Calculations for Diatomic Molecules, and more. - Provides reports on current work in molecular and atomic quantum mechanics - Contains work reported by many of the best scientists in the field - Presents the latest release in the Advances in Quantum Chemistry series
Download or read book Advances in Quantum Chemistry written by and published by Academic Press. This book was released on 1988-08-01 with total page 382 pages. Available in PDF, EPUB and Kindle. Book excerpt: Advances in Quantum Chemistry
Download or read book Ab Initio Molecular Dynamics written by Dominik Marx and published by Cambridge University Press. This book was released on 2009-04-30 with total page 503 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ab initio molecular dynamics revolutionized the field of realistic computer simulation of complex molecular systems and processes, including chemical reactions, by unifying molecular dynamics and electronic structure theory. This book provides the first coherent presentation of this rapidly growing field, covering a vast range of methods and their applications, from basic theory to advanced methods. This fascinating text for graduate students and researchers contains systematic derivations of various ab initio molecular dynamics techniques to enable readers to understand and assess the merits and drawbacks of commonly used methods. It also discusses the special features of the widely used Car–Parrinello approach, correcting various misconceptions currently found in research literature. The book contains pseudo-code and program layout for typical plane wave electronic structure codes, allowing newcomers to the field to understand commonly used program packages and enabling developers to improve and add new features in their code.
Download or read book Methods in Computational Molecular Physics written by Stephen Wilson and published by Springer Science & Business Media. This book was released on 2013-11-11 with total page 554 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume records the lectures given at a NATO Advanced Study Institute on Methods in Computational Molecular Physics held in Bad Windsheim, Germany, from 22nd July until 2nd. August, 1991. This NATO Advanced Study Institute sought to bridge the quite considerable gap which exist between the presentation of molecular electronic structure theory found in contemporary monographs such as, for example, McWeeny's Methods 0/ Molecular Quantum Mechanics (Academic Press, London, 1989) or Wilson's Electron correlation in moleeules (Clarendon Press, Oxford, 1984) and the realization of the sophisticated computational algorithms required for their practical application. It sought to underline the relation between the electronic structure problem and the study of nuc1ear motion. Software for performing molecular electronic structure calculations is now being applied in an increasingly wide range of fields in both the academic and the commercial sectors. Numerous applications are reported in areas as diverse as catalysis and interstellar chernistry, drug design and environmental studies, molecular biology and solid state physics. The range of applications continues to increase as scientists recognize the importance of molecular structure studies to their research activities. Recent years have seen a growing dependence of these applications on program packages, which are often not in the public domain and which may have a somewhat lirnited range of applicability dicta ted by the particular interests and prejudices of the program author.
Download or read book New Electron Correlation Methods and their Applications and Use of Atomic Orbitals with Exponential Asymptotes written by and published by Academic Press. This book was released on 2021-09-28 with total page 354 pages. Available in PDF, EPUB and Kindle. Book excerpt: Advances in Quantum Chemistry presents surveys of current topics in this rapidly developing field one that has emerged at the cross section of the historically established areas of mathematics, physics, chemistry, and biology. It features detailed reviews written by leading international researchers. In this volume the readers are presented with an exciting combination of themes. - 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
Download or read book Characterization Techniques and Tabulations for Organic Nonlinear Optical Materials written by Carl W. Dirk and published by Routledge. This book was released on 2018-05-11 with total page 914 pages. Available in PDF, EPUB and Kindle. Book excerpt: ""Furnishes table of nonlinear optical properties of organic substances as well as experimental procedures for measuring the nonlinearity of the elements tabulated, including composite materials-offering support for scientists and engineers involved in characterizing, optimizing, and producing materials for manufacturing optical devices.
Download or read book New Theoretical Concepts for Understanding Organic Reactions written by Juan Bertrán and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 403 pages. Available in PDF, EPUB and Kindle. Book excerpt: People who attended the NATO Advanced Study Institute (ASI) entitled NEW THEORETICAL CONCEPTS FOR UNDERSTANDING ORGANIC REAC TIONS held at Sant Feliu de Gufxols on the Costa Brava of Spain had a unique experience. They have seen the evolution of the field from qualitative arguments through the generation of Potential Energy Surfaces (PES) to the use of PES in molecular dynamics. The excellent lectures that were dedicated to the various aspects of Potential Energy Surfaces clearly revealed a colossal amount of ma terial that represents our current understanding of the overall problem. It is our hope that the present volume will recreate the excitement in the readers that we all experienced during the meeting in Spain. One can say, without too much exaggeration, that chemistry has become and exercise on potential energy surfaces (PES). Structural (position of the energy minima), spectroscopic (vicinity around the minima), and reactivity (reaction path along the surface) properties may be determined from the analysis of PES. New theoretical tools, together with recent developments in computer technology and programming, have allowed to obtain a better knowledge of these surfaces, and to extract further chemical information from them, so new horizons have been added to Theoretical Organic Chemistry.
Download or read book Lattice 89 written by N. Cabbibo and published by Elsevier. This book was released on 2016-06-03 with total page 787 pages. Available in PDF, EPUB and Kindle. Book excerpt: Lattice 89
Download or read book Structures and Conformations of Non Rigid Molecules written by J. Laane and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 640 pages. Available in PDF, EPUB and Kindle. Book excerpt: From the beginnings of modern chemistry, molecular structure has been a lively area of research and speculation. For more than half a century spectroscopy and other methods have been available to characterize the structures and shapes of molecules, particularly those that are rigid. However, most molecules are at least to some degree non-rigid and this non-rigidity plays an important role in such diverse areas as biological activity, energy transfer, and chemical reactivity. In addition, the large-amplitude vibrations present in non-rigid molecules give rise to unusual low-energy vibrational level patterns which have a dramatic effect on the thermodynamic properties of these systems. Only in recent years has a coherent picture of the energetics and dynamics of the conformational changes inherent in non-rigid (and semi-rigid) molecules begun to emerge. Advances have been made in a number of different experimental areas: vibrational (infrared and Raman) spectroscopy, rotational (microwave) spectroscopy, electron diffraction, and, most recently, laser techniques probing both the ground and excited electronic states. Theoretically, the proliferation of powerful computers coupled with scientific insight has allowed both empirical and ab initio methods to increase our understanding of the forces responsible for the structures and energies of non-rigid systems. The development of theory (group theoretical methods and potential energy surfaces) to understand the unique characteristics of the spectra of these floppy molecules has also been necessary to reach our present level of understanding. The thirty chapters in this volume contributed by the key speakers at the Workshop are divided over the various areas. Both vibrational and rotational spectroscopy have been effective at determining the potential energy surfaces for non-rigid molecules, often in a complementary manner. Recent laser fluorescence work has extended these types of studies to electronic excited states. Electronic diffraction methods provide radial distribution functions from which both molecular structures and compositions of conformational mixtures can be found. Ab initio calculations have progressed substantially over the past few years, and, when carried out at a sufficiently high level, can accurately reproduce (or predict ahead of time) experimental findings. Much of the controversy of the ARW related to the question of when an ab initio is reliable. Since the computer programs are readily available, many poor calculations have been carried out. However, excellent results can be obtained from computations when properly done. A similar situation exists for experimental analyses. The complexities of non-rigid molecules are many, but major strides have been taken to understand their structures and conformational processes.
Download or read book Introduction to Relativistic Quantum Chemistry written by Kenneth G. Dyall and published by Oxford University Press. This book was released on 2007-04-19 with total page 545 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book introduces relativistic methods in quantum chemistry to non-experts and students. Its five sections cover classical relativity background; the Dirac equation; four-component methods, including symmetry, correlation, and properties; approximate methods, including perturbation theory, transformed Hamiltonians, regular approximations, matrix approximations, and pseudopotential methods; and an overview of relativistic effects on bonding
Download or read book Chemical Group Theory written by Danail Bonchev and published by Taylor & Francis. This book was released on 1995 with total page 268 pages. Available in PDF, EPUB and Kindle. Book excerpt: First Published in 2004. Routledge is an imprint of Taylor & Francis, an informa company.
