Electronic Structure of Disordered Alloys, Surfaces and Interfaces

Electronic Structure of Disordered Alloys, Surfaces and Interfaces PDF Author: Ilja Turek
Publisher: Springer Science & Business Media
ISBN: 9780792397984
Category : Science
Languages : en
Pages : 340

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Book Description
An introduction to the study of basic electronic and magnetic properties of complex materials such as alloys, their surfaces, interfaces, and extended defects. Part I explores theoretical background, with chapters on the linear muffin-tin orbital method, Green function method, coherent potential approximation, self- consistency within atomic sphere approximation, and relativistic theory. Part II is devoted to applications including magnetic properties, numerical implementation, and interatomic interactions in alloys. Of interest to researchers in solid state theory, surface science, and computational materials research. Annotation copyrighted by Book News, Inc., Portland, OR.

Introduction to the Electron Theory of Metals

Introduction to the Electron Theory of Metals PDF Author: Uichiro Mizutani
Publisher: Cambridge University Press
ISBN: 9780521587099
Category : Science
Languages : en
Pages : 610

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Book Description
Electron theory of metals textbook for advanced undergraduate students of condensed-matter physics and related disciplines.

Atomic and electronic structures of two-dimensional layers on noble metals

Atomic and electronic structures of two-dimensional layers on noble metals PDF Author: Jalil Shah
Publisher: Linköping University Electronic Press
ISBN: 917685048X
Category :
Languages : en
Pages : 67

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Book Description
Two-dimensional (2D) materials, in the form of a single atomic layer with a crystalline structure, are of interest for electronic applications. Such materials can be formed by a single element, e.g., by group IV or group V elements, or as a 2D surface alloy. As these materials consist of just a single atomic layer, they may have unique properties that are not present in the bulk. The (111) surfaces of the noble metals Ag and Au are important for the preparation of several 2D materials. To investigate the atomic and electronic structures, the following experimental techniques were used in this thesis: angle resolved photoelectron spectroscopy (ARPES), scanning tunneling microscopy (STM) and low energy electron diffraction (LEED). The 2D structures studied in this thesis include arsenene (an As analogue to graphene) and As/Ag(111), Sn/Au(111), and Te/Ag(111) surface alloys. Arsenene has been thoroughly investigated theoretically for many years and several interesting properties important for next generation electronic and optoelectronic devices have been described in the literature. This thesis presents the first experimental evidence of the formation of arsenene. A clean Ag(111) surface was exposed to arsenic in an ultra-high vacuum chamber at an elevated substrate temperature (250 to 350 °C ). The resulting arsenic layer was studied by LEED, STM and ARPES. Both LEED and STM data resulted in a lattice constant of the arsenic layer of 3.6 Å which is consistent with the formation of arsenene. A comparison between the experimental band structure obtained by ARPES and the theoretical band structure of arsenene based on density functional theory (DFT), further verified the formation of arsenene. The As/Ag(111) surface alloy was prepared by exposing clean Ag(111) to arsenic followed by heating to 400 °C. This resulted in an Ag2As surface alloy which formed by the replacement of every third Ag atom by an As atom in a periodic fashion. LEED showed a complex pattern of diffraction spots corresponding to a superposition of three domains of a reconstruction described by a unit cell. STM images revealed a surface with a striped atomic structure with ridges characterized by a local ?3 × ?3 structure. ARPES data showed three alloy related bands of which one can be associated with the ?3 × ?3 structure on the ridges. This band shows a split in momentum space around the point along the direction of a ?3 × ?3 surface Brillouin zone in similarity with a Ge/Ag(111) surface alloy. Sn/Au(111) surface alloys can be prepared with different periodicities. An Au2Sn phase characterized by a ?3 × ?3 periodicity and an Au3Sn phase with a 2 × 2 periodicity are formed containing 0.33 and 0.25 monolayer of Sn, respectively. The clean Au(111) surface itself, shows a complex reconstruction, the so called herringbone structure, that can be viewed as a zig-zag pattern of stripes described by a 22 × ?3 unit cell. The replacement of Au atoms by Sn results in change of the periodicity of the herringbone structure to 26 × ?3 and ? 26 × 2?3 for the Au2Sn and Au3Sn surface alloys, respectively. Furthermore, the local 1 × 1 periodicity of clean Au(111) is replaced by a ?3 × ?3 and a 2 × 2 periodicity as is clear from STM images of the respective cases. ARPES data are presented for the Au2Sn surface alloy, which reveal an electronic band structure with similarities to other striped surface alloys. In particular, the split in momentum space around the point of a ?3 × ?3 surface Brillouin zone is observed also for Au2Sn. A Te-Ag binary surface alloy can be formed by evaporating 1/3 monolayer of Te onto a clean Ag(111) surface followed by annealing. After this preparation, LEED showed sharp ?3 × ?3 diffraction spots that is evidence for a well-ordered surface layer. ARPES data revealed two distinct electronic bands that followed the ?3 × ?3 periodicity. One of these bands showed a small spin-split of the Rashba type. The experimental band structure was compared with the theoretical bands of several atomic models of Te induced structures on Ag(111). An excellent fit was obtained for a Te-Ag surface alloy with a planar honeycomb structure, with one Te and one Ag atom in the unit cell. A semiconducting electronic structure of the Te-Ag surface alloy was inferred from the ARPES data in agreement with the ?0.7 eV band gap predicted by the DFT calculations.

Electronic Structure Methods for Complex Materials

Electronic Structure Methods for Complex Materials PDF Author: Wai-Yim Ching
Publisher: OUP Oxford
ISBN: 0191635065
Category : Science
Languages : en
Pages : 328

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Book Description
Density functional theory (DFT) has blossomed in the past few decades into a powerful tool that is used by experimentalists and theoreticians alike. This book highlights the extensive contributions that the DFT-based OLCAO method has made to progress in this field, and it demonstrates its competitiveness for performing ab initio calculations on large and complex models of practical systems. A brief historical account and introduction to the elements of the theory set the stage for discussions on semiconductors, insulators, crystalline metals and alloys, complex crystals, non-crystalline solids and liquids, microstructure containing systems and those containing impurities, defects, and surfaces, biomolecular systems, and the technique of ab initio core level spectroscopy calculation.

Electronic Structure of Materials

Electronic Structure of Materials PDF Author: Rajendra Prasad
Publisher: Taylor & Francis
ISBN: 1466504706
Category : Science
Languages : en
Pages : 467

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Book Description
Most textbooks in the field are either too advanced for students or don't adequately cover current research topics. Bridging this gap, Electronic Structure of Materials helps advanced undergraduate and graduate students understand electronic structure methods and enables them to use these techniques in their work.Developed from the author's lecture

The Actinides

The Actinides PDF Author: A. J. Freeman
Publisher:
ISBN:
Category :
Languages : en
Pages : 0

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Book Description


Scientific and Technical Aerospace Reports

Scientific and Technical Aerospace Reports PDF Author:
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 1572

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Book Description


Metal Surface Electron Physics

Metal Surface Electron Physics PDF Author: A. Kiejna
Publisher: Elsevier
ISBN: 0080536344
Category : Technology & Engineering
Languages : en
Pages : 312

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Book Description
During the last thirty years metal surface physics, or generally surface science, has come a long way due to the development of vacuum technology and the new surface sensitive probes on the experimental side and new methods and powerful computational techniques on the theoretical side. The aim of this book is to introduce the reader to the essential theoretical aspects of the atomic and electronic structure of metal surfaces and interfaces. The book gives some theoretical background to students of experimental and theoretical physics to allow further exploration into research in metal surface physics.The book consists of three parts. The first part is devoted to classical description of geometry and structure of metal crystals and their surfaces and surface thermodynamics including properties of small metallic particles. Part two deals with quantum-mechanical description of electronic properties of simple metals. It starts from the free electron gas description and introduces the many body effects in the framework of the density functional theory, in order to discuss the basic surface electronic properties of simple metals. This part outlines also properties of alloy surfaces, the quantum size effect and small metal clusters. Part three gives a succinct description of metal surfaces in contact with foreign atoms and surfaces. It treats the work function changes due to alkali metal adsorption on metals, adhesion between metals and discusses the universal aspects of the binding energy curves. In each case extensive reference lists are provided.

Electronic Structure of Metals

Electronic Structure of Metals PDF Author: Nikolaĭ Borisovich Brandt
Publisher:
ISBN:
Category : Electron metallography
Languages : en
Pages : 344

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Book Description


Physical Metallurgy of Refractory Metals and Alloys

Physical Metallurgy of Refractory Metals and Alloys PDF Author: E. M. Savitskii
Publisher: Springer Science & Business Media
ISBN: 1468415727
Category : Technology & Engineering
Languages : en
Pages : 296

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Book Description
The principal reasons which induced the authors to write this book and the features of the book are set forth in the preface to the Russian edition. That section of the science of metals which in Russian is called "metallovedenie" or the "physical chemistry of metals" is generally referred to in scientific and technical literature published in the English language by the term "physical metallurgy." These concepts are much broader than the term" metallography," used in the scientific and technical literature of various countries, and applied solely to research on the interrelationships of the structure and proper ties of metals and alloys. Each science must have its own subject and its own method of research. Certainly, all specialists will agree that metals and alloys, including their solid solutions, mechanical mix tures, and metallic compounds, form the subject of "physical metallurgy" or "physical chemis try of metals." The aim of this science. is to produce a theory and to elucidate the experimental relationships which ought finally to make it possible to calculate quantitatively alloys Of given properties for any working conditions and parameters.