Download or read book Electronic Structure and Defect induced Lattice Relaxation of F center and Hydrogen Defects in the Alkaline earth Oxides MgO CaO written by Jiann-Wien Hsu and published by . This book was released on 1991 with total page 246 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Electronic Structure of the F Center in the Alkaline Earth Oxides written by and published by . This book was released on 1976 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The energy levels and wave functions of the ground and first few singlet and triplet excited states of the F center in MgO, CaO, and SrO were calculated as a function of the nearest neighbor ion positions. Configuration coordinate curves for A/sub 1g/, E/sub g/ and T/sub 2g/ displacements have been constructed and used to interpret the absorption and luminescence bands of the F center. The energy of the 1A/sub 1g/ .-->. 1T/sub 1u/ transition was set near the experimental value in each case by adjusting certain parameters in the model. The calculated energy level schemes partially support the interpretations of published experimental data on the luminescence bands in MgO and CaO and suggest that the 3T/sub 1u/ .-->. 1A/sub 1g/ luminescence in SrO should occur at roughly 0.4 eV. A luminescence band associated with the F center in SrO has not yet been reported. The calculations of the Jahn--Teller coupling constants indicate that the 3T/sub 1u/ state is strongly coupled to the E/sub g/ vibrational mode in CaO and to the T/sub 2g/ mode in MgO and SrO.
Download or read book Dissertation Abstracts International written by and published by . This book was released on 1992-04 with total page 774 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book American Doctoral Dissertations written by and published by . This book was released on 1991 with total page 724 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Electronic Properties of Oxide Insulators written by John E. Wertz and published by . This book was released on 1971 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: Studies of the point defects in the alkaline earth oxides MgO, CaO, and SrO centered upon the trapped-electron of F-type centers, the trapped-hole or V1-type centers and the various valence states of substitutional impurities. Attempts have been made to correlate numerous other electronic properties - optical absorption, luminescence behavior, charge-release, phenomena, and the Hall coefficient with electron spin data. Largely, the behavior has been in accord with prediction, but with some surprises; for example, the F center in MgO was observed to give a photo-induced Hall effect appropriate to holes as the majority carrier, whereas for the CaO and SrO one finds electrons, as expected. This is attributed to the very-low lying ground state of the F center in MgO, i.e., the level lies in the vicinity of the valence band. Two substitutional defects recently studied are the Fe(3+) ion and the Ti(3+) ion in MgO, both with an associated cation vacancy in the next-nearest neighbor cation position. These represent almost ideally simple examples of d1 and/or d5 ions in octahedral-plus-tetragonal symmetry. Recent theoretical studies have been made of the hole trapped adjacent to a positive ion cavancy in order to determine the extent to which the localized model is applicable. Present results are not conclusive. (Author).
Download or read book Electronic Structure of Defects in Oxides Final Report December 1 1979 November 30 1980 Cap Alpha Al2O3 MgAl2O4 written by and published by . This book was released on 1980 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Details of the electronic structure of F-type centers in the series of oxides SrO, CaO, .cap alpha.-Al2O3 and MgAl2O4 have been determined using measurements of photoconductivity, luminescence, and fluorescence lifetimes. Measurements were made over the spectral range 2 to 6.5 eV and over the temperature range 4 to 350°K. The centers were introduced into SrO by electron, on proton or neutron bombardment, into CaO and .cap alpha.-Al2O3 by electron a neutron bombardment or thermochemical coloration, and into MgAl2O4 by particle bombardment. In some cases, notably CaO and .cap alpha.-Al2O3, the photoconductivity behaves differently depending on the method used to introduce the centers. In particular, neutron irradiated and some thermochemically colored samples of sapphire contain an effective electron trap with an optical transition energy of approx. 5.0 eV and a thermal excitation energy of 0.72 eV as determined by measurements of photoconductivity, thermoluminescence and phosphorescence. This trap appears to be structural defect consisting of an aggragate of anion vacancies.
Download or read book Physics Briefs written by and published by . This book was released on 1991 with total page 1094 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Electronic structure of the V and related centres in alkaline earth oxides written by J. H. Harding and published by . This book was released on 1979 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Mass Transport in Oxides written by J. B. Wachtman and published by . This book was released on 1968 with total page 228 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Current Programs written by and published by . This book was released on 1974 with total page 734 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Oxide Surfaces written by and published by Elsevier. This book was released on 2001-05-21 with total page 677 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book is a multi-author survey (in 15 chapters) of the current state of knowledge and recent developments in our understanding of oxide surfaces. The author list includes most of the acknowledged world experts in this field. The material covered includes fundamental theory and experimental studies of the geometrical, vibrational and electronic structure of such surfaces, but with a special emphasis on the chemical properties and associated reactivity. The main focus is on metal oxides but coverage extends from 'simple' rocksalt materials such as MgO through to complex transition metal oxides with different valencies.
Download or read book Ceramic Abstracts written by and published by . This book was released on 1985 with total page 1188 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Point Defects in Solids written by James H. Crawford and published by Springer Science & Business Media. This book was released on 2013-03-09 with total page 568 pages. Available in PDF, EPUB and Kindle. Book excerpt: Crystal defects can no longer be thought of as a scientific curiosity, but must be considered an important aspect of solid-state science. This is largely because many of the more interesting properties of crystalline solids are disproportionately dominated by effects due to a tiny concentration of imperfections in an otherwise perfect lattice. The physics of such lattice defects is not only of significance in a great variety of applications, but is also interesting in its own right. Thus, an extensive science of point defects and dislocations has been constructed during the past two and a half decades. Stimulated by the technological and scientific interest in plasticity, there have appeared in recent years rather a large number of books dealing with dislocations; in the case of point defects, however, only very few broad and extensive treatments have been published. Thus, there are few compre hensive, tutorial sources for the scientist or engineer whose research ac tivities are affected by point defect phenomena, or who might wish to enter the field. It is partially to fill this need that the present treatise aims.
Download or read book Classical And Quantum Dynamics In Condensed Phase Simulations Proceedings Of The International School Of Physics written by Bruce J Berne and published by World Scientific. This book was released on 1998-06-17 with total page 881 pages. Available in PDF, EPUB and Kindle. Book excerpt: The school held at Villa Marigola, Lerici, Italy, in July 1997 was very much an educational experiment aimed not just at teaching a new generation of students the latest developments in computer simulation methods and theory, but also at bringing together researchers from the condensed matter computer simulation community, the biophysical chemistry community and the quantum dynamics community to confront the shared problem: the development of methods to treat the dynamics of quantum condensed phase systems.This volume collects the lectures delivered there. Due to the focus of the school, the contributions divide along natural lines into two broad groups: (1) the most sophisticated forms of the art of computer simulation, including biased phase space sampling schemes, methods which address the multiplicity of time scales in condensed phase problems, and static equilibrium methods for treating quantum systems; (2) the contributions on quantum dynamics, including methods for mixing quantum and classical dynamics in condensed phase simulations and methods capable of treating all degrees of freedom quantum-mechanically.
Download or read book Defects in Solids written by Richard J. D. Tilley and published by John Wiley & Sons. This book was released on 2008-10-10 with total page 549 pages. Available in PDF, EPUB and Kindle. Book excerpt: Provides a thorough understanding of the chemistry and physics of defects, enabling the reader to manipulate them in the engineering of materials. Reinforces theoretical concepts by placing emphasis on real world processes and applications. Includes two kinds of end-of-chapter problems: multiple choice (to test knowledge of terms and principles) and more extensive exercises and calculations (to build skills and understanding). Supplementary material on crystallography and band structure are included in separate appendices.
Download or read book Oxide Ultrathin Films written by Gianfranco Pacchioni and published by John Wiley & Sons. This book was released on 2012-09-19 with total page 526 pages. Available in PDF, EPUB and Kindle. Book excerpt: A wealth of information in one accessible book. Written by international experts from multidisciplinary fields, this in-depth exploration of oxide ultrathin films covers all aspects of these systems, starting with preparation and characterization, and going on to geometrical and electronic structure, as well as applications in current and future systems and devices. From the Contents: Synthesis and Preparation of Oxide Ultrathin Films Characterization Tools of Oxide Ultrathin Films Ordered Oxide Nanostructures on Metal Surfaces Unusual Properties of Oxides and Other Insulators in the Ultrathin Limit Silica and High-K Dielectrics Thin Films in Microelectronics Oxide Passive Films and Corrosion Protection Oxide Films as Catalytic Materials and as Models of Real Catalysts Oxide Films in Spintronics Oxide Ultrathin Films in Solid Oxide Fuel Cells Transparent Conducting and Chromogenic Oxide Films as Solar Energy Materials Oxide Ultrathin Films in Sensor Applications Ferroelectricity in Ultrathin Film Capacitors Titania Thin Films in Biocompatible Materials and Medical Implants Oxide Nanowires for New Chemical Sensor Devices
Download or read book Oxide Materials at the Two Dimensional Limit written by Falko P. Netzer and published by Springer. This book was released on 2016-04-01 with total page 403 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book summarizes the current knowledge of two-dimensional oxide materials. The fundamental properties of 2-D oxide systems are explored in terms of atomic structure, electronic behavior and surface chemistry. The concept of polarity in determining the stability of 2-D oxide layers is examined, charge transfer effects in ultrathin oxide films are reviewed as well as the role of defects in 2-D oxide films. The novel structure concepts that apply in oxide systems of low dimensionality are addressed, and a chapter giving an overview of state-of-the-art theoretical methods for electronic structure determination of nanostructured oxides is included. Special emphasis is given to a balanced view from the experimental and the theoretical side. Two-dimensional materials, and 2-D oxides in particular, have outstanding behavior due to dimensionality and proximity effects. Several chapters treat prototypical model systems as illustrative examples to discuss the peculiar physical and chemical properties of 2-D oxide systems. The chapters are written by renowned experts in the field.
