Download or read book Recent Advances In Computational Chemistry Molecular Integrals Over Slater Orbitals written by Telhat Ozdogan and published by . This book was released on 2008-01-01 with total page 255 pages. Available in PDF, EPUB and Kindle. Book excerpt: The object of this book is to present the methods used in the evaluation of molecular integrals over Slater orbitals, which occur in quantum chemical calculations of atoms, molecules and solids. The evaluation of molecular integrals is a dynamic research field at the heart of the computational chemistry, namely quantum theory of molecular electronic structure. One of the main difficulties in the application of rigorous quantum mechanical methods to the study of the electronic structure of polyatomic molecules has been the evaluation of molecular integrals. The use of Slater functions in molecular calculations was hindered in the 1950s by the enormous computational complexity of molecular integrals, due to the lack of advances in applied mathematics and computer technology. Soon in the 1950s the pragmatic solution was chosen: Slater orbitals were replaced by Gaussian ones in molecular calculations. This situation has been maintained along the last four decades, but it is changing at present and it seems to be inverted in the near future. The fundamental properties of atomic and molecular wave functions, such as nuclear and electron-electron cusps, exponential decay at infinity are known and it is relatively hard to find trial functions to satisfy them. Atom centered Slater functions help to describe the critical region around the nuclei efficiently, hence these have been used in a majority of quantum chemical studies of molecules. This type of basis function is particularly well-suited for atomic and molecular calculations. From the 1990s up to today, many efforts have been made by several groups to elaborate effective procedures for efficient calculation of molecular integrals over Slater orbitals and fructified in new programs for polyatomic molecules that already perform more efficiently than those using Gaussian orbitals in some applications. One of the most promising applications of Slater functions is the highly accurate determination of the electronic energy of ground and excited states, and diverse properties of atoms and molecules using explicit correlated wave functions. In particular the Hylleraas-Configuration Interaction (Hy-CI) method is considered as a generalization of the conventional CI procedure and can be extended to larger systems. Several chapters of this book are devoted to the analytical evaluation of the appearing integrals in the Hy-CI method. We have organized the molecular integrals in this book into the parts: history, atomic integrals, molecular integrals, relativistic integrals and integrals of properties. The integrals are correlated und uncorrelated. In all chapters new recent methods are presented by the authors, and a main topic is reviewed. The first chapter is a delighting historical review about Slater orbitals and the first and recent computer programs. The second chapter is a magnificent mathematical review of all integration methods over correlated atomic wave functions, which is extremely valuable for present and future scientists in this field. The evaluation of new molecular integrals over Slater orbitals with the flexibility of including also non-integer powers is the topic of the third chapter. Some mathematical techniques which can be helpful in the evaluation of correlated and uncorrelated molecular integrals, like the Hamiltonian in Hylleraas coordinates, appear in the fourth chapter. The fifth chapter accounts all the techniques which have been actually programmed in a molecular computer program, including discussions of their efficiency and performance. It gives a deep insight into the actual practical situation. The sixth chapter compiles the results of the only general method of evaluation of all appearing integrals in two-center molecules using the Hy-CI method. Relativistic integrals occurring in the Hy-CI method for the Dirac-Coulomb Hamiltonian are developed in the seventh chapter. In the chapter eight Coulomb integrals for the case of different orbital exponents are evaluated using the Fourier transform method. Finally, the last chapter is dedicated to the calculation of electric multipole moments using Slater orbitals. We believe that the advance of quantum chemistry depends on the efficient evaluation of molecular integrals over Slater orbitals. It is a pleasant duty to acknowledge here in part the wide assistance we have received from Prof. Peter Otto from the University Erlangen-Nürnberg, Germany, Prof. Nazmi Turan Okumusoglu, Rector of Rize University, Turkey, and The Scientific and Technological Research Council of Turkey (TUBITAK), and Prof. Philip E. Hoggan, Clermont University, France.
Download or read book Frontiers in Quantum Systems in Chemistry and Physics written by P.J. Grout and published by Springer Science & Business Media. This book was released on 2008-09-12 with total page 586 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this volume we have collected some of the contributions made to the Twelfth European Workshop on Quantum Systems in Chemistry and Physics (QSCP-XII) in 2007. The workshop was held at Royal Holloway College, the most westerly campusof the University of London,and situated just a stone’s throw from Windsor Great Park. The workshop, which ran from 30 August to 5 September, continued the series that was established by Roy McWeeny in April 1996 with a meeting held at San Miniato, near Pisa. The purpose of the QSCP workshops is to bring together, in an informal atmosphere and with the aim of fostering collaboration, those chemists and physicists who share a common ?eld of interest in the theory of the quantum many-body problem. Quantum mechanics provides a theoretical foundation for our understandingof the structure,propertiesanddynamicsof atoms, moleculesandthe solid state, in terms of their component particles: electrons and nuclei. The study of ‘Quantum Systems in Chemistry and Physics’ therefore underpins many of the emerging?elds in twenty-?rstcenturyscience andtechnology:nanostructure,smart materials, drug design – to name but a few. Members of the workshop were keen to discuss their research and engage in collaboration centred upon the development of fundamental and innovative theory which would lead to the exploration of new concepts. The proceedings of all of the workshops, which have been held annually since 1996, have been published both to disseminate the latest developments within the wider community and to stimulate further collaboration.
Download or read book Advances in Quantum Chemistry written by and published by Elsevier. This book was released on 2023-09-28 with total page 400 pages. Available in PDF, EPUB and Kindle. Book excerpt: Advances in Quantum Chemistry, Volume 88 presents the latest ongoing research at the forefront of Electronic structure theory. Chapters in the updated release include Spin-constrained Hartree-Fock and the generator coordinate method for the 2-site Hubbard model, Analytical evaluation of Hylleraas-CI Coulomb and Hybrid two-center Integrals over Slater orbitals, Hartree-Fock-Roothaan Theory of Molecular Compton Profiles Via Position Space Method, Analysis of Research Trend on the Molecular Integrals Over Slater Type Orbitals, An efficient approximation for accelerating convergence of numerical power series, Results for the 1D-Schroedinger equation, The aims and objectives of algebraic molecular orbital theory, and much more. Includes new theoretical methods Provides state-of-the art electron correlation, methods and effects Covers the challenge of excited electronic states
Download or read book Solving the Schr dinger Equation written by Paul L. A. Popelier and published by World Scientific. This book was released on 2011 with total page 375 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Schrdinger equation is the master equation of quantum chemistry. The founders of quantum mechanics realised how this equation underpins essentially the whole of chemistry. However, they recognised that its exact application was much too complicated to be solvable at the time. More than two generations of researchers were left to work out how to achieve this ambitious goal for molecular systems of ever-increasing size. This book focuses on non-mainstream methods to solve the molecular electronic Schrdinger equation. Each method is based on a set of core ideas and this volume aims to explain these ideas clearly so that they become more accessible. By bringing together these non-standard methods, the book intends to inspire graduate students, postdoctoral researchers and academics to think of novel approaches. Is there a method out there that we have not thought of yet? Can we design a new method that combines the best of all worlds?
Download or read book Computational Quantum Chemistry written by Joseph J. W. McDouall and published by Royal Society of Chemistry. This book was released on 2013 with total page 291 pages. Available in PDF, EPUB and Kindle. Book excerpt: Computational Quantum Chemistry presents computational electronic structure theory as practiced in terms of ab initio waveform methods and density functional approaches. Getting a full grasp of the field can often prove difficult, since essential topics fall outside of the conventional chemistry education. This professional reference book provides a comprehensive guide to the field. Postgraduate students and experienced researchers alike will appreciate Joseph McDouall's engaging writing style. The book is divided into five sections, each covering a major aspect of the field and with its own introduction. Molecular properties and relativistic effects are also discussed. An appendix describes software packages and website for further reading to enhance the knowledge gained from the book. Professor McDouall has more than 20 years experience in theoretical chemistry; as a reader at the University of Manchester his research interests include the application of quantum chemical methods to the elucidation of chemical problems and the development and implementation of electronic structure methods that permit the accurate prediction of chemical structures and molecular properties.
Download or read book Analytical Methods Using Slater Type Orbitals in Quantum Chemistry written by and published by . This book was released on 1992 with total page 89 pages. Available in PDF, EPUB and Kindle. Book excerpt: Our main concern is with the development of a Slater-type orbital (STO) multicenter molecular integral package for use with standard ab initio quantum chemistry codes such as the Columbus code and Alchemy. Significant advances have been made toward this goal. A new strategy has been adopted: First program all molecular integrals in Mathematics (a computer algebra language that can give arbitrary precision with our alpha-function method); then, using assured accurate results as a guide, use FORTRAN to obtain speed and acceptable accuracy. We believe that this dual thrust will finally crack the 'intractable' problem of STO multicenter integrals. Applications will soon be made to real molecules.
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 Advances in Quantum Chemistry written by and published by Academic Press. This book was released on 1974-11-15 with total page 312 pages. Available in PDF, EPUB and Kindle. Book excerpt: Advances in Quantum Chemistry
Download or read book Computational Techniques in Quantum Chemistry and Molecular Physics written by Geerd H.F. Diercksen and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 570 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book contains the transcripts of the lectures presented at the NATO Advanced study Institute on "Computational Techniques in Quantum Chemistry and Molecular Physics", held at Ramsau, Germany, 4th - 21st Sept. 1974. Quantum theory was developed in the early decades of this century and was first applied to problems in chemistry and molecular physics as early as 1927. It soon emerged however, that it was impossible to con sider any but the simplest systems in any quantita tive detail because of the complexity of Schrodinger's equation which is the basic equation for chemical and molecular physics applications. This remained the si tuation until the development, after 1950, of elec tronic digital computers. It then became possible to attempt approximate solutions of Schrodinger's equa tion for fairly complicated systems, to yield results which were sufficiently accurate to make comparison with experiment meaningful. Starting in the early nineteen sixties in the United States at a few centres with access to good computers an enormous amount of work went into the development and implementation of schemes for approximate solu tions of Schrodinger's equation, particularly the de velopment of the Hartree-Fock self-consistent-field scheme. But it was soon found that the integrals needed for application of the methods to molecular problems are far from trivial to evaluate and cannot be easily approximated.
Download or read book Electron Correlation in Molecules ab initio Beyond Gaussian Quantum Chemistry written by and published by Academic Press. This book was released on 2016-01-28 with total page 441 pages. Available in PDF, EPUB and Kindle. Book excerpt: Electron Correlation in Molecules – ab initio Beyond Gaussian Quantum Chemistry presents a series of articles concerning important topics in quantum chemistry, including 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. 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 The volume includes review on all the topics treated by world renown authors and cutting edge research contributions.
Download or read book Computational Quantum Chemistry written by Charles M. Quinn and published by Elsevier. This book was released on 2002-02-28 with total page 246 pages. Available in PDF, EPUB and Kindle. Book excerpt: Computational Quantum Chemistry removes much of the mystery of modern computer programs for molecular orbital calculations by showing how to develop Excel spreadsheets to perform model calculations and investigate the properties of basis sets. Using the book together with the CD-ROM provides a unique interactive learning tool. In addition, because of the integration of theory with working examples on the CD-ROM, the reader can apply advanced features available in the spreadsheet to other applications in chemistry, physics, and a variety of disciplines that require the solution of differential equations.This book and CD-ROM makes a valuable companion for instructors, course designers, and students. It is suitable for direct applications in practical courses in theoretical chemistry and atomic physics, as well as for teaching advanced features of Excel in IT courses.
Download or read book Advances in the Theory of Quantum Systems in Chemistry and Physics written by Philip E. Hoggan and published by Springer Science & Business Media. This book was released on 2011-11-16 with total page 630 pages. Available in PDF, EPUB and Kindle. Book excerpt: Advances in the Theory of Quantum Systems in Chemistry and Physics is a collection of 32 selected papers from the scientific contributions presented at the 15th International Workshop on Quantum Systems in Chemistry and Physics (QSCP-XV), held at Magdalene College, Cambridge, UK, from August 31st to September 5th, 2010. This volume discusses the state of the art, new trends, and the future of methods in molecular quantum mechanics and their applications to a wide range of problems in chemistry, physics, and biology. The breadth and depth of the scientific topics discussed during QSCP-XV are gathered in seven sections: I. Fundamental Theory; II. Model Atoms; III. Atoms and Molecules with Exponential-Type Orbitals; IV. Density-Oriented Methods; V. Dynamics and Quantum Monte-Carlo Methodology; VI. Structure and Reactivity; VII. Complex Systems, Solids, Biophysics. Advances in the Theory of Quantum Systems in Chemistry and Physics is written for research students and professionals in Quantum systems of chemistry and physics. It also constitutes and invaluable guide for those wishing to familiarize themselves with research perspectives in the domain of quantum systems for thematic conversion or simply to gain insight into the methodological developments and applications to physics chemistry and biology that have actually become feasible by the end of 2010.
Download or read book State of The Art of Molecular Electronic Structure Computations Correlation Methods Basis Sets and More written by and published by Academic Press. This book was released on 2019-09-07 with total page 360 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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
Download or read book Problem Solving in Computational Molecular Science written by Stephen Wilson and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 421 pages. Available in PDF, EPUB and Kindle. Book excerpt: For all practical purposes the basic physical equations governing the behaviour of a system at the molecular level can only be solved approximately. The key issue in any reliable and accurate computational study in molecular physics and quantum chemistry is the adoption of a suitable model which contains the essential physics and chemistry, is computationally tractable, and preferably amenable to systematic refinement. The provision of advice on the choice of an appropriate model for a specific problem has so far received scant attention. This issue is becoming acute as `standard' software packages are becoming widely available and are being increasingly heavily used in both the academic and industrial sectors by researchers who have received no special training in the theoretical physics and chemistry that underpins them. This volume provides researchers whose background may not be in the computational molecular sciences with the necessary background to make intelligent use of the methods available by performing reliable calculations of appropriate accuracy and making a considered interpretation of the data so obtained.
Download or read book Recent Advances In Density Functional Methods Part Ii written by Delano Pun Chong and published by World Scientific. This book was released on 1997-05-14 with total page 340 pages. Available in PDF, EPUB and Kindle. Book excerpt: Of all the different areas in computational chemistry, density functional theory (DFT) enjoys the most rapid development. Even at the level of the local density approximation (LDA), which is computationally less demanding, DFT can usually provide better answers than Hartree-Fock formalism for large systems such as clusters and solids. For atoms and molecules, the results from DFT often rival those obtained by ab initio quantum chemistry, partly because larger basis sets can be used. Such encouraging results have in turn stimulated workers to further investigate the formal theory as well as the computational methodology of DFT.This Part II expands on the methodology and applications of DFT. Some of the chapters report on the latest developments (since the publication of Part I in 1995), while others extend the applications to wider range of molecules and their environments. Together, this and other recent review volumes on DFT show that DFT provides an efficient and accurate alternative to traditional quantum chemical methods. Such demonstration should hopefully stimulate frutiful developments in formal theory, better exchange-correlation functionals, and linear scaling methodology.
Download or read book Introduction to Computational Chemistry written by Frank Jensen and published by John Wiley & Sons. This book was released on 2017-02-06 with total page 677 pages. Available in PDF, EPUB and Kindle. Book excerpt: Introduction to Computational Chemistry 3rd Edition provides a comprehensive account of the fundamental principles underlying different computational methods. Fully revised and updated throughout to reflect important method developments and improvements since publication of the previous edition, this timely update includes the following significant revisions and new topics: Polarizable force fields Tight-binding DFT More extensive DFT functionals, excited states and time dependent molecular properties Accelerated Molecular Dynamics methods Tensor decomposition methods Cluster analysis Reduced scaling and reduced prefactor methods Additional information is available at: www.wiley.com/go/jensen/computationalchemistry3
Download or read book Basis Sets in Computational Chemistry written by Eva Perlt and published by Springer Nature. This book was released on 2021-05-06 with total page 255 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book addresses the construction and application of the major types of basis sets for computational chemistry calculations. In addition to a general introduction, it includes mathematical basics and a discussion of errors arising from incomplete or inappropriate basis sets. The different chapters introduce local orbitals and orbital localization as well as Slater-type orbitals and review basis sets for special applications, such as those for correlated methods, solid-state calculations, heavy atoms and time-dependent adaptable Gaussian bases for quantum dynamics simulations. This detailed review of the purpose of basis sets, their design, applications, possible problems and available solutions provides graduate students and beginning researchers with information not easily obtained from the available textbooks and offers valuable supporting material for any quantum chemistry or computational chemistry course at the graduate and/or undergraduate level. This book is also useful as a guide for researchers who are new to computational chemistry but are willing to extend their research tools by applying such methods.