Multiplets of Transition-Metal Ions in Crystals provides information pertinent to ligand field theory. This book discusses the fundamentals of quantum mechanics and the theory of atomic spectra. Comprised of 10 chapters, this book starts with an overview of the qualitative nature of the splitting of the energy level as well as the angular behavior of the wavefunctions. This text then examines the problem of obtaining the energy eigenvalues and eigenstates of the two-electron systems, in which two electrons are accommodated in the t2g and eg shells in a variety of ways. Other chapters discuss the ligand-field potential, which is invariant to any symmetry operation in the group to which symmetry of the system belongs. This book discusses as well the approximate method of expressing molecular orbitals (MO) by a suitable linear combination of atomic orbitals (AO). The final chapter discusses the MO in molecules and the self-consistent field theory of Hartree–Fock. This book is a valuable resource for research physicists, chemists, electronic engineers, and graduate students.

I.- 1. Introduction.- 2. Conventional Magnetism Diagrams and Their Limitations. Present State of the Art.- 3. Tensor Operator Algebra for Point Groups.- 3.1. Tensor Operators and the Wigner-Eckart Theorem.- 3.2. 3-? and 6-? Symbols.- 3.3. Tensor Operators in Subgroups of SO(3).- 3.4. Kronecker and Scalar Products of Tensor Operators.- 3.5. Tensor Operators of the Ligand Field.- 4. The Weak-Field Method.- 4.1. The Hamiltonian, States, and Wave Functions.- 4.2. The Various Coefficients.- 4.3. Matrix Elements.- 4.4. Calculation of Magnetic Susceptibility.- 5. The Intermediate-Field Method.- 5.1.

"Optical Properties of 3d-Ions in Crystals: Spectroscopy and Crystal Field Analysis" discusses spectral, vibronic and magnetic properties of 3d-ions in a wide range of crystals, used as active media for solid state lasers and potential candidates for this role. Crystal field calculations (including first-principles calculations of energy levels and absorption spectra) and their comparison with experimental spectra, the Jahn-Teller effect, analysis of vibronic spectra, materials science applications are systematically presented. The book is intended for researchers and graduate students in crystal spectroscopy, materials science and optical applications. Dr. N.M. Avram is an Emeritus Professor at the Physics Department, West University of Timisoara, Romania; Dr. M.G. Brik is a Professor at the Institute of Physics, University of Tartu, Estonia.

This book describes in detail the main concepts of theoretical spectroscopy of transition metal and rare-earth ions. It shows how the energy levels of different electron configurations are formed and calculated for the ions in a free state and in crystals, how group theory can help in solving main spectroscopic problems, and how the modern DFT-based methods of calculations of electronic structure can be combined with the semi-empirical crystal field models. The style of presentation makes the book helpful for a wide audience ranging from graduate students to experienced researchers. Performance of optical materials crucially depends on the impurity ions intentionally introduced into the crystalline host materials. The color of these materials, their emission and absorption spectra can be understood by analyzing the relations between the electronic properties of impurity ions and host crystal structure, which constitutes the main content of this book. It describes in detail the main concepts of theoretical spectroscopy of transition metal and rare earth ions.

These proceedings report the lectures and seminars presented at the NATO Advanced Study Institute on "Optical Properties of Ions in Solids," held at Erice, Italy, June 6-21, 1974. The Institute was the first activity of the International School of Atomic and Molecular Spectroscopy of the "Ettore Majorana" Centre for Scientific Culture. The Institute consisted of a series of lectures on optical properties of ions in solids that, starting at a fundamental level, finally reached the current level of research. The sequence of lectures and the organization of the material taught were in keeping with a didactical presentation. In essence the Institute had the two-fold purpose of organizing what was known on the subject, and updating the knowledge in the field. Fif'teen series of lectures for a total of 44 hours were given. Five one-hour seminars and five twenty-minute seminars were presented. A total of 57 participants came from 40 laboratories in the following countries: Belgium, Canada, France, Germany, Ireland, Israel, Italy, Netherlands; Polatid, Romania, Switzerland, the United Ki~gdom, and the United States. The secretaries of the Institute were: D. Pacheco for the scientific aspects and A. La Francesca for the administrative aspects of the meeting. These proceedings report the lectures, the one-hour seminars (abstracts only) and the twenty-minute- seminars (titles only). The proceedings report also the contributions sent by Prof. K. Rebane and Dr. L. A. Rebane who, unfortunately, were not able to come.

The study of the spontaneous formation of nanostructures in single crystals of several compounds is now a major area of research in strongly correlated electrons. These structures appear to originate in the competition of phases. The book addresses nanoscale phase separation, focusing on the manganese oxides known as manganites that have the colossal magnetoresistance (CMR) effect of potential relevance for device applications. It is argued that the nanostructures are at the heart of the CMR phenomenon. The book contains updated information on manganite research directed to experts, both theorists and experimentalists. However, graduate students or postdocs will find considerable introductory material, including elements of computational physics.

In the last few years, much attention has been given by theoretical chemists to the development of more accurate model functionals and faster computational techniques including excited electronic states. The 8th International Conference on the Applications of Density Functional Theory to Chemistry and Physics, held in Rome, Italy, on 6-10 September 1999, gathered chemists and physicists to present and discuss state-of-the-art methodological developments and applications of density functional theory (DFT) to increasingly complex systems. The scientists shared their knowledge and experience in DFT, enabling them to face the challenges posed by the needs of high level modeling and simulation in their disciplines. The meeting was opened with an exciting lecture delivered by Nobel laureate W Kohn.The growing use of DFT in studying organic, inorganic and organometallic molecules, clusters and solids provided the basis for the success of the conference, whose main contributions are collected in this invaluable book.

In the last few years, much attention has been given by theoretical chemists to the development of more accurate model functionals and faster computational techniques including excited electronic states. The 8th International Conference on the Applications of Density Functional Theory to Chemistry and Physics, held in Rome, Italy, on 6-10 September 1999, gathered chemists and physicists to present and discuss state-of-the-art methodological developments and applications of density functional theory (DFT) to increasingly complex systems. The scientists shared their knowledge and experience in DFT, enabling them to face the challenges posed by the needs of high level modeling and simulation in their disciplines. The meeting was opened with an exciting lecture delivered by Nobel laureate W Kohn. The growing use of DFT in studying organic, inorganic and organometallic molecules, clusters and solids provided the basis for the success of the conference, whose main contributions are collected in this invaluable book.