Atomic and Electronic Structure of Surfaces

Theoretical Foundations

Author: Michel Lannoo

Publisher: Springer Science & Business Media

ISBN:

Category: Science

Page: 256

View: 294

Surfaces and interfaces play an increasingly important role in today's solid state devices. In this book the reader is introduced, in a didactic manner, to the essential theoretical aspects of the atomic and electronic structure of surfaces and interfaces. The book does not pretend to give a complete overview of contemporary problems and methods. Instead, the authors strive to provide simple but qualitatively useful arguments that apply to a wide variety of cases. The emphasis of the book is on semiconductor surfaces and interfaces but it also includes a thorough treatment of transition metals, a general discussion of phonon dispersion curves, and examples of large computational calculations. The exercises accompanying every chapter will be of great benefit to the student.

Atomic and Electronic Structure of Surfaces

Theoretical Foundations

Author: Michel Lannoo

Publisher: Springer

ISBN:

Category: Science

Page: 256

View: 184

Surfaces and interfaces play an increasingly important role in today's solid state devices. In this book the reader is introduced, in a didactic manner, to the essential theoretical aspects of the atomic and electronic structure of surfaces and interfaces. The book does not pretend to give a complete overview of contemporary problems and methods. Instead, the authors strive to provide simple but qualitatively useful arguments that apply to a wide variety of cases. The emphasis of the book is on semiconductor surfaces and interfaces but it also includes a thorough treatment of transition metals, a general discussion of phonon dispersion curves, and examples of large computational calculations. The exercises accompanying every chapter will be of great benefit to the student.

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

Author: Jalil Shah

Publisher: Linköping University Electronic Press

ISBN:

Category:

Page: 44

View: 636

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.

Atomic and Electronic Structure of Metals and Alloys

Clean Surfaces and Chemisorbed Molecules. Progress Report

Author:

Publisher:

ISBN:

Category:

Page: 8

View: 866

The accomplishments of the work done under DOE sponsorship are summarized in the list of publications at the end of this narrative. Here we give a brief description of the nature and the significance of the accomplishments. The activity can be roughly subdivided into three parts: studies of surface alloys, studies of epitaxial ultra-thin films, and studies of electron band structure of metals. The list reflects the developments of particular areas of research and the phasing out of others as this was suggested by the interest in, and the success of, specific experimental projects.

Atomic and Electronic Structure of Solids

Author: Efthimios Kaxiras

Publisher: Cambridge University Press

ISBN:

Category: Science

Page: 676

View: 700

Graduate-level textbook for physicists, chemists and materials scientists.

The Diamond Surface

Atomic and Electronic Structure

Author: Bradford Bennett Pate

Publisher:

ISBN:

Category: Atomic structure

Page: 252

View: 826

Introduction to the Properties of Crystal Surfaces

International Series on Materials Science and Technology

Author: J. M. Blakely

Publisher: Elsevier

ISBN:

Category: Science

Page: 274

View: 556

Introduction to the Properties of Crystal Surfaces is an introductory text on crystal surfaces and their properties. A variety of phenomena, including electron emission, adsorption and oxidation, adhesion, friction, nucleation and epitaxial growth, and heterogeneous catalysis, are described by considering the details of the atomic and electronic structure in the surface region. This volume is comprised of seven chapters and begins with a discussion on the thermodynamics of surfaces, along with the equilibrium configuration at the intersection of interfaces and the effects of curvature of crystalline surfaces. The next chapter examines the properties of interfaces in multi-component systems, followed by an analysis of experimental measurements of surface tension in solids. The atomic structure of crystal surfaces and some theoretical aspects of surface studies are also considered, and experimental methods in used in such studies are outlined. The final chapter deals with two atomic processes that are involved in a number of reactions at crystal surfaces: surface atomic diffusion and adsorption. This book is intended for senior undergraduates in a materials science type of curriculum or those beginning research work in the field or associated areas.

Concepts in Surface Physics

Author: M.-C. Desjonqueres

Publisher: Springer Science & Business Media

ISBN:

Category: Science

Page: 607

View: 201

A tutorial treatment of the main concepts of the physics of crystal surfaces. Emphasis is placed on simplified calculations and the corresponding detailed analytical derivations, that are able to throw light on the most important physical mechanisms. More rigorous techniques, which often require a large amount of computer time, are also explained. Wherever possible, the theory is compared to practice, with the experimental methods being described from a theoretical rather than a technical viewpoint. The topics treated include thermodynamic and statistical properties of clean and adsorbate-covered surfaces, atomic structure, vibrational properties, electronic structure, and the theory of physisorption and chemisorption. The whole is rounded off with new excercises.

Electronic Structure of Alloys, Surfaces and Clusters

Author: Abhijit Mookerjee

Publisher: CRC Press

ISBN:

Category: Technology & Engineering

Page: 384

View: 416

Understanding the electronic structure of solids is a basic part of theoretical investigation in physics. Application of investigative techniques requires the solid under investigation to be "periodic." However, this is not always the case. This volume addresses three classes of "non-periodic" solids currently undergoing the most study: alloys, surfaces and clusters. Understanding the electronic structure of these systems is fundamental not only for the basic science, but also constitutes a very important step in various technological aspects, such as tuning their stabilities, chemical and catalytic reactivities and magnetism. Expert practitioners give an up-to-date account of the field with enough detailed background so that even a newcomer can follow the development. The theoretical framework is discussed in addition to the present status of knowledge in the field. Electronic Structure of Alloys, Surfaces and Clusters also includes an extensive bibliography which provides a comprehensive reading list of work on the topic.

Atomic and Electronic Structure of Metals and Alloys

Clean Surfaces and Chemisorbed Molecules].

Author:

Publisher:

ISBN:

Category:

Page: 4

View: 960

Ultrapure Tb was further purified and surface cleaning procedures developed for basal plane and (11{bar 2}0) surface of Tb. Structure of both surfaces was found to be relaxed: (0001) is contracted by 3.9% in the first and expanded by 1.4% in second interlayer spacing; (11{bar 2}0) is contracted by 3.3% in first layer and shows a change in registry. Thin films of Gd, Tb, Dy, Ho, and Er were grown on W{l_brace}110{r_brace} substrate in ultrahigh vacuum. Studies have been carried out on epitaxial systems involving Cu, Fe and Mn on Fe and Pt, Cu, and Pd substrates, respectively; new metastable crystalline phases have been found. Studies of possible ferromagnetism in 4d elements (Rh, Ru) and relativistic effects in electron band structure of Cu{l_brace}111{r_brace} have been completed and published. Plans for the following year are given.

Principles of Surface Physics

Author: Friedhelm Bechstedt

Publisher: Springer Science & Business Media

ISBN:

Category: Science

Page: 342

View: 506

An innovative, unified, and comprehensive treatment of the geometric and electronic structure of surfaces. The book emphasizes fundamental aspects, such as the principles of surface crystallography and thermodynamics, the forces driving the rearrangement of the atoms, and the relationship between bonding and electronic structure. It especially illuminates the relationship between surface orientation, chemistry, energetics, and the resulting properties. Principles of Surface Physics develops general physical arguments and methods that enable readers to analyse novel surfaces and interfaces of new materials. This makes the book an indispensable reference to all those studying growth, surface-molecule interactions, self-assembled structures, and materials engineering.

Electronic Structure of Materials

Author: Adrian P. Sutton

Publisher: Clarendon Press

ISBN:

Category:

Page: 276

View: 154

This book describes the modern real-space approach to electronic structures and properties of crystalline and non-crystalline materials in a form readily accessible to undergraduates in materials science, physics, and chemistry. - ;This book describes the modern real-space approach to electronic structures and properties of crystalline and non-crystalline materials in a form readily accessible to undergraduates in materials science, physics, and chemistry. -

Lectures On Solid Surfaces And Interfaces - Proceedings Of The International School On Surface Physics

Author: D S Wang

Publisher: World Scientific

ISBN:

Category:

Page: 300

View: 171

This proceedings contains 9 lectures given by active research scientists, introducing the latest developments in the field of surface physics. The main topics cover both experimental and theoretical aspects of the atomic and electronic structure of semiconductor surface, its characterization by direct and inverse photoemission and STM, chemisorption and bonding on semiconductor, growth of III-V compound semiconductor and metal surface, metal-semiconductor interface and metal silicides.