Strong Coulomb Correlations in Electronic Structure Calculations


Book Description

Materials where electrons show nearly localized rather than itinerant behaviour, such as the high-temperature superconducting copper oxides, or manganate oxides, are attracting interest due to their physical properties and potential applications. For these materials, the interaction between electrons, or electron correlation, plays an important role in describing their electronic strucuture, and the standard methods for the calculation of their electronic spectra based on the local density approximation (LDA) breakdown. This is the first attempt to describe recent approaches that go beyond the concept of the LDA, to successfully describe the electronic structure of narrow-band materials.




Electronic Structure Calculations for Solids and Molecules


Book Description

Electronic structure problems are studied in condensed matter physics and theoretical chemistry to provide important insights into the properties of matter. This 2006 graduate textbook describes the main theoretical approaches and computational techniques, from the simplest approximations to the most sophisticated methods. It starts with a detailed description of the various theoretical approaches to calculating the electronic structure of solids and molecules, including density-functional theory and chemical methods based on Hartree-Fock theory. The basic approximations are thoroughly discussed, and an in-depth overview of recent advances and alternative approaches in DFT is given. The second part discusses the different practical methods used to solve the electronic structure problem computationally, for both DFT and Hartree-Fock approaches. Adopting a unique and open approach, this textbook is aimed at graduate students in physics and chemistry, and is intended to improve communication between these communities. It also serves as a reference for researchers entering the field.




Proceedings of MEST 2012: Electronic Structure Methods with Applications to Experimental Chemistry


Book Description

Advances in Quantum Chemistry 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. It features detailed reviews written by leading international researchers. This volume focuses on the theory of heavy ion physics in medicine. - Advances in Quantum Chemistry presents surveys of current topics in this rapidly developing field and this volume focuses on the theory of heavy ion physics in medicine




Electron Correlations and Materials Properties


Book Description

This volume, the proceedings of a 1998 international workshop, provides experimental evidence of the effects of correlation on the physical, chemical, and mechanical properties of materials, as well as the theoretical/computational methodology that has been developed for their study.




Electronic Structure


Book Description

The study of the electronic structure of materials is at a momentous stage, with the emergence of computational methods and theoretical approaches. Many properties of materials can now be determined directly from the fundamental equations for the electrons, providing insights into critical problems in physics, chemistry, and materials science. This book provides a unified exposition of the basic theory and methods of electronic structure, together with instructive examples of practical computational methods and real-world applications. Appropriate for both graduate students and practising scientists, this book describes the approach most widely used today, density functional theory, with emphasis upon understanding the ideas, practical methods and limitations. Many references are provided to original papers, pertinent reviews, and widely available books. Included in each chapter is a short list of the most relevant references and a set of exercises that reveal salient points and challenge the reader.




Electronic Structure of Strongly Correlated Materials


Book Description

Electronic structure and physical properties of strongly correlated materials containing elements with partially filled 3d, 4d, 4f and 5f electronic shells is analyzed by Dynamical Mean-Field Theory (DMFT). DMFT is the most universal and effective tool used for the theoretical investigation of electronic states with strong correlation effects. In the present book the basics of the method are given and its application to various material classes is shown. The book is aimed at a broad readership: theoretical physicists and experimentalists studying strongly correlated systems. It also serves as a handbook for students and all those who want to be acquainted with fast developing filed of condensed matter physics.




Electronic Structure of Alloys, Surfaces and Clusters


Book Description

Understanding the electronic structure of solids is a basic part of theoretical investigation in physics. Application of investigative techniques requires the solid under investigation to be "periodic." However, this is not always the case. This volume addresses three classes of "non-periodic" solids currently undergoing the most study: alloys, surfaces and clusters. Understanding the electronic structure of these systems is fundamental not only for the basic science, but also constitutes a very important step in various technological aspects, such as tuning their stabilities, chemical and catalytic reactivities and magnetism. Expert practitioners give an up-to-date account of the field with enough detailed background so that even a newcomer can follow the development. The theoretical framework is discussed in addition to the present status of knowledge in the field. Electronic Structure of Alloys, Surfaces and Clusters also includes an extensive bibliography which provides a comprehensive reading list of work on the topic.




Computational Approaches in Physics


Book Description

Computational Approaches in Physics reviews computational schemes which are used in the simulations of physical systems. These range from very accurate ab initio techniques up to coarse-grained and mesoscopic schemes. The choice of the method is based on the desired accuracy and computational efficiency. A bottom-up approach is used to present the various simulation methods used in Physics, starting from the lower level and the most accurate methods, up to particle-based ones. The book outlines the basic theory underlying each technique and its complexity, addresses the computational implications and issues in the implementation, as well as present representative examples. A link to the most common computational codes, commercial or open source is listed in each chapter. The strengths and deficiencies of the variety of techniques discussed in this book are presented in detail and visualization tools commonly used to make the simulation data more comprehensive are also discussed. In the end, specific techniques are used as bridges across different disciplines. To this end, examples of different systems tackled with the same methods are presented. The appendices include elements of physical theory which are prerequisites in understanding the simulation methods.




Full-Potential Electronic Structure Method


Book Description

This is a book describing electronic structure theory and application within the framework of a methodology implemented in the computer code RSPt. In 1986, when the code that was to become RSPt was developed enough to be useful, it was one of the ?rst full-potential, all-electron, relativistic implem- tations of DFT (density functional theory). While RSPt was documented p- asitically in many publications describing the results of its application, it was many years before a publication explicitly describing aspects of the method appeared. In the meantime, several excellent all-electron, full-potential me- ods had been developed, published, and become available. So why a book about RSPt now? The code that became RSPt was initially developed as a personal research tool, rather than a collaborative e?ort or as a product. As such it required some knowledge of its inner workings to use, and as it was meant to be m- imally ?exible, the code required experience to be used e?ectively. These - tributes inhibited, but did not prevent, the spread of RSPt as a research tool. While applicable across the periodic table, the method is particularly useful in describing a wide range of materials, including heavier elements and c- pounds, and its ?exibility provides targeted accuracy and a convenient and accurate framework for implementing and assessing the e?ect of new models.




Quantum Chemistry of Solids


Book Description

Quantum Chemistry of Solids delivers a comprehensive account of the main features and possibilities of LCAO methods for the first principles calculations of electronic structure of periodic systems. The first part describes the basic theory underlying the LCAO methods applied to periodic systems and the use of Hartree-Fock(HF), Density Function theory(DFT) and hybrid Hamiltonians. The translation and site symmetry consideration is included to establish connection between k-space solid –state physics and real-space quantum chemistry. The inclusion of electron correlation effects for periodic systems is considered on the basis of localized crystalline orbitals. The possibilities of LCAO methods for chemical bonding analysis in periodic systems are discussed. The second part deals with the applications of LCAO methods for calculations of bulk crystal properties, including magnetic ordering and crystal structure optimization. In the second edition two new chapters are added in the application part II of the book. Chapter 12 deals with the recent LCAO calculations and illustrates the efficiency of the scalar-relativistic LCAO method for solids, containing heavy atoms. Chapter 13 deals with the symmetry properties and the recent applications of LCAO method to inorganic nanotubes. New material is added to chapter 9 devoted to LCAO calculations of perfect-crystal properties. The possibilities of LCAO method for calculation of the high-frequency dielectric constants of crystals and the description of phase transitions in solids are discussed. The efficiency of LCAO method in the quantum-mechanics-molecular dynamics approach to the interpretation of x-ray absorption and EXAFS spectra is illustrated. A new section is devoted to recent LCAO calculations of electronic, vibrational and magnetic properties of tungstates MeWO4 (Me: Fe,Co,Ni,Cu,Zn,Cd).