Molecular Orbitals And Their Energies Studied By The Semiempirical Ham Method

Author : Einar Lindholm,Leif Asbrink
Publisher : Springer Science & Business Media
Page : 301 pages
File Size : 42,6 Mb
Release : 2012-12-06
Category : Science
ISBN : 9783642455957

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Molecular Orbitals and their Energies, Studied by the Semiempirical HAM Method by Einar Lindholm,Leif Asbrink Pdf

This treatment of molecular and atomic physics is primarily meant as a textbook. It is intended for both chemists and physicists. ·It can be read without much knowledge of quantum mechanics or mathematics, since all such details are explained-. It has developed through a series of lectures at the Royal Institute of Technology. The content is to about 50 % theoretical and to 50 % experimental. The reason why the authors, who are experimentalists, went into theory is the following. When we during the beginning of the 1970's measured photo electron spectra of organic molecules, it appeared to be impossible to understand them by use of available theoretical calculations. To handle hydrocarbons we ( together with C. Fridh ) constructed in 1972 a purely empirical procedure, SPINDO [1] which has proved to be useful, but the extension to molecules with hetero atoms appeared to be difficult. One of us ( L.A.) proposed then another purely ~~E!E!~~! EE2~~~~E~ ( Hydrogenic Atoms in Molecules, HAM/1, unpublished), in which the Fock matrix elements f5..y were parametrized using Slater's shielding concept. The self-repulsion was compensated by a term "-1". The §~~2~~_~ff2E~, HAM/2 [2] , started from the total energy E:. of the molecule. The atomic parts of L used the Slater shielding constants, and the bond parts of E. were taken from SPINDO. The Fock matrix elements Fpv were then obtained from E in a conventional way.

Author : Eugene S. Kryachko,Eduardo V. Ludeña
Publisher : Springer Science & Business Media
Page : 862 pages
File Size : 41,5 Mb
Release : 2012-12-06
Category : Science
ISBN : 9789400919709

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Energy Density Functional Theory of Many-Electron Systems by Eugene S. Kryachko,Eduardo V. Ludeña Pdf

Author : R.M. Erdahl,Vedene H. Smith Jr.
Publisher : Springer Science & Business Media
Page : 718 pages
File Size : 51,8 Mb
Release : 2012-12-06
Category : Science
ISBN : 9789400938557

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Density Matrices and Density Functionals by R.M. Erdahl,Vedene H. Smith Jr. Pdf

THE COLEMAN SYMPOSIUM This collection of papers is dedicated to Albert John Coleman for his enthusiastic devotion to teaching and research and his many scientific accomplishments. John was born in Toronto on May 20, 1918 and 21 years later graduated from the University of Toronto in mathematics. Along the way he teamed up with Irving Kaplansky and Nathan Mendelson to win the first William Lowell Putnam Mathematical Competition in 1938. He earned his M.A. at Princeton in 1942 and then his Ph.D. at Toronto in 1943 in relativistic quantum mechanics under the direction of Leopold Infeld. During this period he was secretary of the Student Christian Movement in Toronto. Later, in 1945, he became traveling secretary of the World's Student Christian Federation in Geneva and in this capacity visited some 100 universities in 20 countries in the next four years. He spent the 50's as a member of the faculty at the University of Toronto and for 20 years, starting in 1960, he served as Dupuis Professor of Mathematics and Head of the Department at Queen's University. Since 1983 he has been Professor Emeritus at Queen's.

Author : Robert G. Parr,Yang Weitao
Publisher : Oxford University Press
Page : 344 pages
File Size : 48,6 Mb
Release : 1994-05-26
Category : Science
ISBN : 9780195357738

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Density-Functional Theory of Atoms and Molecules by Robert G. Parr,Yang Weitao Pdf

This book is a rigorous, unified account of the fundamental principles of the density-functional theory of the electronic structure of matter and its applications to atoms and molecules. Containing a detailed discussion of the chemical potential and its derivatives, it provides an understanding of the concepts of electronegativity, hardness and softness, and chemical reactivity. Both the Hohenberg-Kohn-Sham and the Levy-Lieb derivations of the basic theorems are presented, and extensive references to the literature are included. Two introductory chapters and several appendices provide all the background material necessary beyond a knowledge of elementary quantum theory. The book is intended for physicists, chemists, and advanced students in chemistry.

Author : A.L. Horvath
Publisher : Elsevier
Page : 1505 pages
File Size : 55,8 Mb
Release : 2012-12-02
Category : Science
ISBN : 9780444596734

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Molecular Design by A.L. Horvath Pdf

This book is a systematic presentation of the methods that have been developed for the interpretation of molecular modeling to the design of new chemicals. The main feature of the compilation is the co-ordination of the various scientific disciplines required for the generation of new compounds. The five chapters deal with such areas as structure and properties of organic compounds, relationships between structure and properties, and models for structure generation. The subject is covered in sufficient depth to provide readers with the necessary background to understand the modeling techniques. The book will be of value to chemists in industries involved in the manufacture of organic chemicals such as solvents refrigerants, blood substitutes, etc. It also serves as a reference work for researchers, academics, consultants, and students interested in molecular design.

Author : W. Jakubetz
Publisher : Springer Science & Business Media
Page : 195 pages
File Size : 55,8 Mb
Release : 2012-12-06
Category : Science
ISBN : 9783642565113

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Methods in Reaction Dynamics by W. Jakubetz Pdf

Methods in Reaction Dynamics is a collection of lectures given at the 1999 Mariapfarr Workshop in Theoretical Chemistry. Arranged as a series of detailed reviews, it provides an overview of quantum mechanical techniques used to describe and simulate the dynamics and kinetics of elementary chemical reactions. The volume provides in-depth discussions of selected topics in Theoretical Chemistry, such as quantum methods in theoretical and computational reaction dynamics and kinetics; time-dependent, time-independent and mixed quantum-classical techniques. Some of the topics have not been reviewed before in detail.

Author : M. Defranceschi,C. Le Bris
Publisher : Springer Science & Business Media
Page : 247 pages
File Size : 55,7 Mb
Release : 2012-12-06
Category : Science
ISBN : 9783642572371

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Mathematical Models and Methods for Ab Initio Quantum Chemistry by M. Defranceschi,C. Le Bris Pdf

On the occasion of the fourth International Conference on Industrial and Applied Mathematics!, we decided to organize a sequence of 4 minisymposia devoted to the mathematical aspects and the numerical aspects of Quantum Chemistry. Our goal was to bring together scientists from different communities, namely mathematicians, experts at numerical analysis and computer science, chemists, just to see whether this heterogeneous set of lecturers can produce a rather homogeneous presentation of the domain to an uninitiated audience. To the best of our knowledgde, nothing of this kind had never been tempted so far. It seemed to us that it was the good time for doing it, both . because the interest of applied mathematicians into the world of computational chemistry has exponentially increased in the past few years, and because the community of chemists feels more and more concerned with the numerical issues. Indeed, in the early years of Quantum Chemistry, the pioneers (Coulson, Mac Weeny, just to quote two of them) used to solve fundamental equations modelling toy systems which could be simply numerically handled in view of their very limited size. The true difficulty arose with the need to model larger systems while possibly taking into account their interaction with their environment. Hand calculations were no longer possible, and computing science came into the picture.

Author : Alexander F. Sax
Publisher : Springer Science & Business Media
Page : 242 pages
File Size : 44,5 Mb
Release : 2012-12-06
Category : Science
ISBN : 9783642468797

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Potential Energy Surfaces by Alexander F. Sax Pdf

Potential Energy Surfaces is a collection of lectures given at the 1996 Mariapfarr Workshop in Theoretical Chemistry, organized by Alexander F. Sax. The Mariapfarr Workshops' aim is to discuss in-depth topics in Theoretical Chemistry. The target group of these workshops is graduate students and postdocs.

Author : Robert Ponec
Publisher : Springer Science & Business Media
Page : 135 pages
File Size : 48,6 Mb
Release : 2012-12-06
Category : Science
ISBN : 9783642468179

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Overlap Determinant Method in the Theory of Pericyclic Reactions by Robert Ponec Pdf

The author summarizes the development and the applications of overlap determinant method in various fields of pericyclic reactivity. The greatest advantage of this new method lies in its remarkable simplicity and flexibility owing to which it opens an interesting possibility of the systematic investigation of important mechanistic problems of pericyclic reactivity which were so far beyond the scope of other existing techniques.

Author : Sandor Fliszar
Publisher : Springer Science & Business Media
Page : 182 pages
File Size : 48,9 Mb
Release : 2013-03-09
Category : Science
ISBN : 9783642514920

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Atoms, Chemical Bonds and Bond Dissociation Energies by Sandor Fliszar Pdf

Chemical bonds, their intrinsic energies in ground-state molecules and the energies required for their actual cleavage are the subject of this book. The theory, modelled after a description of valence electrons in isolated atoms, explains how intrinsic bond energies depend on the amount of electronic charge carried by the bond-forming atoms. It also explains how bond dissociation depends on these charges. While this theory vividly explains thermochemical stability, future research could benefit from a better understanding of bond dissociation: if we learn how the environment of a molecule affects its charges, we also learn how it modifies bond dissociation in that molecule. This essay is aimed at theoretical and physical-organic chemists who are looking for new perspectives to old problems.

Author : A. Lagana,A. Riganelli
Publisher : Springer Science & Business Media
Page : 334 pages
File Size : 45,5 Mb
Release : 2000-11-27
Category : Science
ISBN : 3540412026

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Reaction and Molecular Dynamics by A. Lagana,A. Riganelli Pdf

The amazing growth of computational resources has made possible the modeling of complex chemical processes. To develop these models one needs to proceed from rigorous theoretical methods to approximate ones by exploiting the potential of innovative architectural features of modern concurrent processors. This book reviews some of the most advanced theoretical approaches in the field of molecular reaction dynamics in order to cope as rigorously as possible with the complexity of real systems.

Author : Pekka Pyykkö
Publisher : Springer Science & Business Media
Page : 362 pages
File Size : 44,6 Mb
Release : 2013-06-29
Category : Science
ISBN : 9783642518850

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Relativistic Theory of Atoms and Molecules III by Pekka Pyykkö Pdf

Relativistic effects are of major importance for understanding the properties of heavier atoms and molecules. Volumes I-III of Relativistic Theory of Atoms and Molecules constitute the only available bibliography on related calculations. In Volume III, 3792 new references covering 1993-1999 are added to the database. The material is characterized by an analysis of the respective papers. The volume gives the user a comprehensive bibliography on relativistic atomic and molecular calculations, including studies on the Dirac equation and related solid-state work.

Author : R. Carbo-Dorca,D. Robert,L. Amat,X. Girones,E. Besalu
Publisher : Springer Science & Business Media
Page : 123 pages
File Size : 42,6 Mb
Release : 2012-12-06
Category : Science
ISBN : 9783642572739

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Molecular Quantum Similarity in QSAR and Drug Design by R. Carbo-Dorca,D. Robert,L. Amat,X. Girones,E. Besalu Pdf

The authors introduce the concept of Molecular Quantum Similarity, developed in their laboratory, in a didactic form. The basis of the concept combines quantum theoretical calculations with molecular structure and properties even for large molecules. They give definitions and procedures to compute similarities molecules and provide graphical tools for visualization of sets of molecules as n-dimensional point charts.

Author : A.J. Coleman,V.I. Yukalov
Publisher : Springer Science & Business Media
Page : 300 pages
File Size : 49,6 Mb
Release : 2000-04-14
Category : Science
ISBN : 354067148X

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Reduced Density Matrices by A.J. Coleman,V.I. Yukalov Pdf

The authors demonstrate that the essential information about order in, and energy levels of physical systems is encapsulated in the second order reduced density matrix. They have discovered an algorithm to obtain a reasonable accurate expression for the 2-matrix of an N-particle state to make nearly all properties of matter which are of interest to chemists and physicists accessible.

Author : Serafin Fraga,J.M.Robert Parker,Jennifer M. Pocock
Publisher : Springer Science & Business Media
Page : 284 pages
File Size : 44,5 Mb
Release : 2013-04-17
Category : Science
ISBN : 9783642514999

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Computer Simulations of Protein Structures and Interactions by Serafin Fraga,J.M.Robert Parker,Jennifer M. Pocock Pdf

Protein engineering endeavors to design new peptides and proteins or to change the structural and/or functional characteristics of existing ones for specific purposes, opening the way for the development of new drugs. This work develops in a comprehensive way the theoretical formulation for the methods used in computer-assisted modeling and predictions, starting from the basic concepts and proceeding to the more sophisticated methods, such as Monte Carlo and molecular dynamics. An evaluation of the approximations inherent to the simulations will allow the reader to obtain a perspective of the possible deficiencies and difficulties and approach the task with realistic expectations. Examples from the authors laboratories, as well as from the literature provide useful information.