Simple Models of Magnetism


Book Description

For hundreds of years, models of magnetism have been pivotal in the understanding and advancement of science and technology, from the Earth's interpretation as a magnetic dipole to quantum mechanics, statistical physics, and modern nanotechnology. This book is the first to envision the field of magnetism in its entirety. It complements a rich literature on specific models of magnetism and provides an introduction to simple models, including some simple limits of complicated models. The book is written in an easily accessible style, with a limited amount of mathematics, and covers a wide range of quantum-mechanical, finite-temperature, micromagnetic and dynamical models. It deals not only with basic magnetic quantities, such as moment, Curie temperature, anisotropy, and coercivity, but also with modern areas such as nanomagnetism and spintronics, and with 'exotic' themes, as exemplified by the polymer analogy of magnetic phase transitions. Throughout the book, a sharp line is drawn between simple and simplistic models, and much space is devoted to discuss the merits and failures of the individual model approaches.







High-pressure Molecular Spectroscopy


Book Description

This book compiles spectroscopy methods under high pressure to investigate different systems such as guest-host interactions, chemical reactions, multiferroics, lanthanide ions and-doped glasses or in general inorganic materials. Among others, luminescence studies, inelastic scattering as well as infrared and Raman studies under high pressure are discussed and described regarding various applications.




High Magnetic Fields


Book Description

This three-volume book provides a comprehensive review of experiments in very strong magnetic fields that can only be generated with very special magnets. The first volume is entirely devoted to the technology of laboratory magnets: permanent, superconducting, high-power water-cooled and hybrid; pulsed magnets, both nondestructive and destructive (megagauss fields). Volumes 2 and 3 contain reviews of the different areas of research where strong magnetic fields are an essential research tool. These volumes deal primarily with solid-state physics; other research areas covered are biological systems, chemistry, atomic and molecular physics, nuclear resonance, plasma physics and astrophysics (including QED).




Equilibrium Thermodynamics


Book Description

This textbook provides an exposition of equilibrium thermodynamics and its applications to several areas of physics with particular attention to phase transitions and critical phenomena. The applications include several areas of condensed matter physics and include also a chapter on thermochemistry. Phase transitions and critical phenomena are treated according to the modern development of the field, based on the ideas of universality and on the Widom scaling theory. For each topic, a mean-field or Landau theory is presented to describe qualitatively the phase transitions. These theories include the van der Waals theory of the liquid-vapor transition, the Hildebrand-Heitler theory of regular mixtures, the Griffiths-Landau theory for multicritical points in multicomponent systems, the Bragg-Williams theory of order-disorder in alloys, the Weiss theory of ferromagnetism, the Néel theory of antiferromagnetism, the Devonshire theory for ferroelectrics and Landau-de Gennes theory of liquid crystals. This textbook is intended for students in physics and chemistry and provides a unique combination of thorough theoretical explanation and presentation of applications in both areas. Chapter summaries, highlighted essentials and problems with solutions enable a self sustained approach and deepen the knowledge.




The Theory of Magnetism II


Book Description

What is thermodynamics? What does statistical physics teach us? In the pages of this slim book, we confront the answers. The reader will discover that where thermodynami cs provi des a 1 arge scal e, macroscopi c theory of the ef fects of temperature on physical systems, statistical mechanics provides the microscopic analysis of these effects which, invariably, are the results of thermal disorder. A number of systems in nature undergo dramatic changes in aspect and in their properties when subjected to changes in ambient temperature or pres sure, or when electric or magnetic fields are applied. The ancients already knew that a liquid, a solid, or a gas can represent different states of the same matter. But what is meant by "state"? It is here that the systematic study of magnetic materials has provided one of the best ways of examining this question, which is one of the principal concerns of statistical physics (alias "statistical mechanics") and of modern thermodynamics.




Molecular Magnetism: From Molecular Assemblies to the Devices


Book Description

Molecular Magnetism: From Molecular Assemblies to the Devices reviews the state of the art in the area. It is organized in two parts, the first of which introduces the basic concepts, theories and physical techniques required for the investigation of the magnetic molecular materials, comparing them with those used in the study of classical magnetic materials. Here the reader will find: (i) a detailed discussion of the electronic processes involved in the magnetic interaction mechanisms of molecular systems, including electron delocalization and spin polarization effects; (ii) a presentation of the available theoretical models based on spin and Hubbard Hamiltonians; and (iii) a description of the specific physical investigative techniques used to characterize the materials. The second part presents the different classes of existing magnetic molecular materials, focusing on the possible synthetic strategies developed to date to assemble the molecular building blocks ranging from purely organic to inorganic materials, as well as on their physical properties and potential applications. These materials comprise inorganic and organic ferro- and ferrimagnets, high nuclearity organic molecules and magnetic and metallic clusters, spin crossover systems, charge transfer salts (including fulleride salts and organic conductors and superconductors), and organized soft media (magnetic liquid crystals and Langmuir-Blodgett films).