Condensed Matter Physics / Materials

Acids and bases are ubiquitous in chemistry. Our understanding of them, however, is dominated by their behaviour in water. Transfer to non-aqueous solvents leads to profound changes in acid-base strengths and to the rates and equilibria of many processes: for example, synthetic reactions involving acids, bases, and nucleophiles; isolation of pharmaceutical actives through salt formation; formation of zwitter-ions in amino acids; and chromatographic separation of substrates. This book seeks to enhance our understanding of acids and bases by reviewing and analysing their behaviour in non-aqueous solvents. The behaviour is related where possible to that in water, but correlations and contrasts between solvents are also presented. Fundamental background material is provided in the initial chapters: quantitative aspects of acid–base equilibria, including definitions and relationships between solution pH and species distribution; the influence of molecular structure on acid strengths; and acidity in aqueous solution. Solvent properties are reviewed, along with the magnitude of the interaction energies of solvent molecules with (especially) ions; the ability of solvents to participate in hydrogen bonding and to accept or donate electron pairs is seen to be crucial. Experimental methods for determining dissociation constants are described in detail. In the remaining chapters, dissociation constants of a wide range of acids in three distinct classes of solvent are discussed: protic solvents, such as alcohols, which are strong hydrogen-bond donors; basic, polar aprotic solvents, such as dimethylformamide; and low-basicity and low-polarity solvents, such as acetonitrile and tetrahydrofuran. Dissociation constants of individual acids vary over more than twenty orders of magnitude among the solvents, and there is a strong differentiation between the response of neutral and charged acids to solvent change. Ion-pairing and hydrogen-bonding equilibria, such as between phenol and phenoxide ions, play an increasingly important role as the solvent polarity decreases, and their influence on acid–base equilibria and salt formation is described.

Acoustic microscopy enables you to image and measure the elastic properties of materials with the resolution of a good microscope. By using frequencies in the microwave range, it is possible to make the acoustic wavelength comparable with the wavelength of light, and hence to achieve a resolution comparable with an optical microscope. The contrast gives information about the elastic properties and structure of the sample. Since acoustic waves can propagate in materials, acoustic microscopy can be used for interior imaging, with high sensitivity to defects such as delaminations. Solids can support both longitudinal and transverse acoustic waves. At surfaces a combination of the two known as Rayleigh waves can propagate, and in many circumstances these dominate the contrast in acoustic microscopy. Contrast theory accounts for the variation of signal with defocus, V(z). Acoustic microscopy can image and measure properties such as anisotropy and features such as surface boundaries and cracks. A scanning probe microscope can be used to detect ultrasonic vibration of a surface with resolution in the nanometre range, thus beating the diffraction limit by operating in the extreme near‐field. This 2nd edition of Acoustic Microscopy has a major new chapter on the technique and applications of acoustically exited probe microscopy.

The field of ferroelectricity has greatly expanded and changed recently. In addition to classical organic and inorganic ferroelectrics as well as composite ferroelectrics new fields and materials have appeared, important for both basic science and application and showing technological promise for novel multifunctional devices. Most of these fields were unknown or inactive 20 to 40 years ago. Such new fields are multiferroic magnetoelectric systems, where the spontaneous polarization and the spontaneous magnetization are allowed to coexist, incommensurate ferroelectrics, where the periodicity of the order parameter is incommensurate to the periodicity of the underlying basic crystal lattice, ferroelectric liquid crystals, dipolar glasses, relaxor ferroelectrics, ferroelectric thin films and nanoferroelectrics. These new fields are in addition to basic physical interest also of great technological importance and allow for new memory devices, spintronic applications and electro‐optic devices. They are also important for applications in acoustics, robotics, telecommunications and medicine. New developments in relaxors allow for giant electromechanical and electrocaloric effects. The book is primarily intended for material scientists working in research or industry. It is also intended for graduate and doctoral students and can be used as a textbook in graduate courses. Finally, it should be useful for everybody following the development of modern solid‐state physics.

Tomography provides three-dimensional images of heterogeneous materials or engineering components, and offers an unprecedented insight into their internal structure. By using X-rays generated by synchrotrons, neutrons from nuclear reactors, or electrons provided by transmission electron microscopes, hitherto invisible structures can be revealed which are not accessible to conventional tomography based on X-ray tubes. This book provides detailed descriptions of the recent developments in this field, especially the extension of tomography to materials research and engineering. The book is grouped into four parts: a general introduction into the principles of tomography, image analysis and the interactions between radiation and matter, and one part each for synchrotron X-ray tomography, neutron tomography, and electron tomography. Within these parts, individual chapters written by different authors describe important versions of tomography, and also provide examples of applications to demonstrate the capacity of the methods.

The subject of this book is the Casimir effect, i.e., a manifestation of zero-point oscillations of the quantum vacuum in the form of forces acting between closely spaced bodies. It is a purely quantum effect. There is no force acting between neutral bodies in classical electrodynamics. The Casimir effect has become an interdisciplinary subject. It plays an important role in various fields of physics such as condensed matter physics, quantum field theory, atomic and molecular physics, gravitation and cosmology, and mathematical physics. Most recently, the Casimir effect has been applied to nanotechnology and for obtaining constraints on the predictions of unification theories beyond the Standard Model. The book assembles together the field-theoretical foundations of this phenomenon, the application of the general theory to real materials, and a comprehensive description of all recently performed measurements of the Casimir force, including the comparison between experiment and theory. There is increasing interest in forces of vacuum origin. Numerous new results have been obtained during the last few years which are not reflected in the literature, but are very promising for fundamental science and nanotechnology. The book provides a source of information which presents a critical assessment of all of the main results and approaches contained in published journal papers. It also proposes new ideas which are not yet universally accepted but are finding increasing support from experiment.

This book covers the theory, practicalities, and the extensive applications of neutron powder diffraction in materials science, physics, chemistry, mineralogy, and engineering. Various highlight applications of neutron powder diffraction are outlined in the introduction, then the theory is developed and instrumentation described sufficient for a return to the applications. The book covers the use of neutron powder diffraction in the solution (hard) and refinement (more straightforward) of crystal and magnetic structures, applications of powder diffraction in quantitative phase analysis, extraction of microstructural information from powder diffraction patterns, and the applications of neutron diffraction in studies of elastic properties and for the measurement of residual stress. Additional theory to underpin these various applications is developed as required.

Brownian motion is the incessant motion of small particles immersed in an ambient medium. It is due to fluctuations in the motion of the medium particles on the molecular scale. The name has been carried over to other fluctuation phenomena. This book treats the physical theory of Brownian motion. The extensive mathematical theory, which treats the subject as a subfield of the general theory of random processes, is touched on but not presented in any detail. Random or stochastic process theory and statistical mechanics are the primary tools. The first eight chapters treat the stochastic theory and some applications. The next six present the statistical mechanical point of view. Then follows chapters on applications to diffusion, noise, and polymers, followed by a treatment of the motion of interacting Brownian particles. The book ends with a final chapter treating simulation, fractals, and chaos.

The book presents a self-contained exposition of the mode-coupling theory for the evolution of glassy dynamics in liquids. This theory is based on polynomial expressions for the correlations of force fluctuations in terms of those of density fluctua-tions. These mode-coupling polynomials are motivated as descriptions of the cage-effect-induced transient localization of particles in condensed matter. It is proven that the implied regular mode-coupling equations of motion determine uniquely models for a correlation-function description of the dynamics. This holds for all choices of the polynomial coefficients, which serve as coupling constants. The arrested parts of the correlations are solutions of fixed-point equations. They exhibit spontaneous singularities, which are equivalent to the bifurcation singularities of the real roots of real polynomials. They deal with idealized liquid-glass and glass-glass transitions. Driving the coupling constants towards their critical values, the correlation functions exhibit the evolution of complex dynamics. Its subtleties are due to the interplay of nonlinearities and divergent retardation effects. The book discusses that the relaxation features are similar to those observed in experimental and molecular-dynamics-simulation studies of con-ventional liquids and colloids. Asymptotic expansions are derived for the mode-coupling-theory functions for small frequencies and small separations of the coupling constants from the transition values. The leading-order asymptotic contributions provide an understanding of the essential facets of the scenarios. The leading-asymptotic corrections are deduced and applied to quantify the evolution of the leading-order description.

Nowadays, information technology is based on semiconductor and ferromagnetic materials. Information processing and computation are performed using electron charge in semiconductor transistors and integrated circuits, and the information is stored by electron spins on magnetic high-density hard disks. Recently, a new branch of physics and nanotechnology, called magneto-electronics, spintronics, or spin electronics, has emerged, which aims to exploit both the charge and the spin of electrons in the same device. A broader goal is to develop new functionality that does not exist separately in a ferromagnet or a semiconductor. This book presents new directions in the development of spin electronics in both the basic physics and the technology which will become the foundation of future electronics.

In the past twenty years, new experimental approaches, improved models and progress in simulation techniques have brought new insights into longstanding issues concerning dislocation-based plasticity in crystalline materials. During this period, three-dimensional dislocation dynamics (DD) simulations appeared and reached maturity. Their major objective is to contribute to the multiscale modelling of plastic flow by bridging the gap between atomic-scale studies of dislocation core properties and continuum models. Three-dimensional DD simulations are now becoming accessible to a wide range of users. This book presents to students and researchers in materials science and mechanical engineering a comprehensive coverage of the physical body of knowledge on which they are based and of current unsolved issues that deserve further investigation. The contents include classical studies, which are too often ignored, recent experimental and theoretical advances, and a discussion of selected applications on various topics. As the field is very broad, an extensive bibliography is provided. Chapter 1 presents an introduction to the topics discussed in the ensuing chapters. Chapters 2 and 3 are devoted to crystal plasticity, from elementary core and elastic dislocation properties to the mechanical response. The first of these discusses essentially FCC metals, and the second discusses BCC metals, some transition HCP metals and silicon. Chapter 4 presents basic elements that are common to all three-dimensional DD simulations, as well as characteristic features of each existing code, and Chapter 5 provides a synthesis of applications of DD simulations to large-scale crystals and to size effects in small-scale crystals.