Download or read book Scanning Tunneling Microscopy Studies of Surface Structures of Icosahedral Al Cu Fe Quasicrystals written by and published by . This book was released on 2002 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Three papers are included in this dissertation. The first paper: ''Structural aspects of the fivefold quasicrystalline Al-Cu-Fe surface from STM and dynamical LEED studies'', is in press with ''Surface Science''. The second paper: ''An STM study of the atomic structure of the icosahedral Al-Cu-Fe fivefold surface'' is submitted to ''Physical Review B, Rapid Communication''. The third paper: ''Pseudomorphic starfish: arrangement of extrinsic metal atoms on a quasicrystalline substrate'' is submitted to ''Nature''. Following the third paper are general conclusions and appendices that document the published paper ''Structural aspects of the three-fold surface of icosahedral Al-Pd-Mn'' (appearing in volume 461, issue 1-3 of ''Surface Science'' on page L521-L527, 2000), the design as well as the specifications of the aluminum evaporator used in the aluminum deposition study in this dissertation, an extended discussion of the aluminum deposition on the quasicrystalline surface, and the STM database.
Download or read book Scanning Tunneling Microscopy Studies of Surface Structures of Icosahedral Al Cu Fe Quasicrystals written by Tanhong Cai and published by . This book was released on 2001 with total page 270 pages. Available in PDF, EPUB and Kindle. Book excerpt: Similar structural features can be identified in the atomically-dense planes generated from one of the available bulk structure models. Based on these results, we conclude that the fivefold i-AlCuFe surface corresponds to a two-dimensional cut of the bulk material. After examining the clean surface, we investigate the nucleation and growth of aluminium metallic thin films on the quasicrystalline i-Al-Cu-Fe fivefold surface. Upon deposition at room temperature, aluminium adatoms nucleate as pentagonal "starfish" with uniform size and in the same orientation. The same structure features are observed for different fluxes at low coverages. Based on the experimental results and the available bulk structure model, we identify the specific nucleation sites on the substrate and develop a model for the formation of the pentagonal starfish.
Download or read book Scanning Tunneling Microscopy Studies of Fivefold Surfaces of Icosahedral Al Pd Mn Quasicrystals and of Thin Silver Films on Those Surfaces written by Baris Unal and published by . This book was released on 2008 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Surface Structure Determination by LEED and X rays written by Wolfgang Moritz and published by Cambridge University Press. This book was released on 2022-08-25 with total page 475 pages. Available in PDF, EPUB and Kindle. Book excerpt: Discover exciting new developments and applications of LEED and X-ray diffraction, alongside detailed introductory material.
Download or read book Scanning Tunneling Microscopy and Spectroscopy of Aluminum Based Quasicrystals and Approximants written by Ruben Rafael Mäder and published by Logos Verlag Berlin GmbH. This book was released on 2010 with total page 167 pages. Available in PDF, EPUB and Kindle. Book excerpt: On the nanometer scale, the local variation of the electronic density of states of aluminum based complex metallic alloys (quasicrystals and approximants) is experimentally investigated by low temperature scanning tunneling spectroscopy. We report on the correlation between the local variations of the electronic density of states and the electrical resistivity. The surface structure is investigated by scanning tunneling microscopy, low energy electron diffraction, and X-ray photoemission diffraction. Experimental results are interpreted on the basis of the respective bulk structure models.
Download or read book Scanning Tuneeling Microscopy Studies of Fivefold Surfaces of Icosahedral Al Pd Mn Quasicrystals and of Thin Silver Films on Those Surfaces written by and published by . This book was released on 2008 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The present work in this dissertation mainly focuses on the clean fivefold surfaces of i-Al-Pd-Mn quasicrystals as well as the nucleation and growth of Ag films on these surfaces. In addition, Ag film growth on NiAl(110) has been explored in the frame of this dissertation. First, we have investigated the equilibration of a fivefold surface of icosahedral Al-Pd-Mn quasicrystal at 900-915 K and 925-950 K, using Omicron variable temperature scanning tunneling microscope (STM). Annealing at low temperatures resulted in many voids on some terraces while the others were almost void-free. After annealing at 925-950K, void-rich terraces became much rarer. Our STM images suggest that through growth and coalescence of the voids, a different termination becomes exposed on host terraces. All of these observations in our study indicate that even after the quasicrystalline terrace-step structure appears, it evolves with time and temperature. More specifically, based on the STM observations, we conclude that during the annealing a wide range of energetically similar layers nucleate as surface terminations, however, with increasing temperature (and time) this distribution gets narrower via elimination of the metastable void-rich terraces. Next, we have examined the bulk structural models of icosahedral Al-Pd-Mn quasicrystal in terms of the densities, compositions and interplanar spacings for the fivefold planes that might represent physical surface terminations. In our analyses, we mainly have focused on four deterministic models which have no partial or mixed occupancy but we have made some comparisons with an undeterministic model. We have compared the models with each other and also with the available experimental data including STM, LEED-IV, XPD and LEIS. In all deterministic models, there are two different families of layers (a pair of planes), and the nondeterministic model contains similar group of planes. These two families differ in terms of the chemical decoration of their top planes. Hence, we name them as Pd+(with Pd) and Pd-(without Pd). Based on their planer structure and the step height, it can be said that these two families can be viable surface terminations. However, besides the Pd content, these two sets differ in terms of relative densities of their top planes as well as the gap separating the layer from the nearest atomic plane. The experimental data and other arguments lead to the conclusion that the Pd- family is favored over the Pd+. This has an important implication on the interpretation of local motifs seen in the high resolution STM images. In other words, the dark stars are not formed by cut-Bergmans rather they are formed by cut-Mackays.
Download or read book JJAP written by and published by . This book was released on 1987 with total page 1010 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Aperiodic Crystals written by Ted Janssen and published by Oxford University Press. This book was released on 2018 with total page 551 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book explains aperiodic crystals, which cannot be described by the classical model of 3-dimensional periodicities. The study of these new types of material necessitates describing them in dimensions larger than three. It describes the physical and mathematical methods to solve and characterize them, and to understand their physical properties.
Download or read book Quasicrystals The State Of The Art 2nd Edition written by David Divincenzo and published by World Scientific. This book was released on 1999-11-16 with total page 635 pages. Available in PDF, EPUB and Kindle. Book excerpt: Quasicrystals: The State of the Art has proven to be a useful introduction to quasicrystals for mathematicians, physicists, materials scientists, and students. The original intent was for the book to be a progress report on recent developments in the field. However, the authors took care to adopt a broad, pedagogical approach focusing on points of lasting value. Many subtle and beautiful aspects of quasicrystals are explained in this book (and nowhere else) in a way that is useful for both the expert and the student.In this second edition, some authors have appended short notes updating their essays. Two new chapters have been added. Chapter 16, by Goldman and Thiel, reviews the experimental progress since the first edition (1991) in making quasicrystals, determining their structure, and finding applications. In Chapter 17, Steinhardt discusses the quasi-unit cell picture, a promising, new approach for describing the structure and growth of quasicrystals in terms of a single, repeating, overlapping cluster of atoms.
Download or read book Coverings of Discrete Quasiperiodic Sets written by Peter Kramer and published by Springer. This book was released on 2003-07-01 with total page 287 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this up-to-date review and guide to most recent literature, the expert authors develop concepts related to quasiperiodic coverings and describe results. The text describes specific systems in 2 and 3 dimensions with many illustrations, and analyzes the atomic positions in quasicrystals.
Download or read book New Horizons In Quasicrystals Research And Applications Proceedings Of The Conference written by Alan I Goldman and published by World Scientific. This book was released on 1997-02-03 with total page 358 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this volume the following topics are discussed: existing and potential applications of quasicrystals, surface and interface properties of quasicrystals, and potential new quasicrystalline materials.It gathers contributions from world-renowned researchers in the field of quasicrystals, experts in fields such as surface science, materials preparation and mechanical properties, as well as representatives of industry to discuss possible directions for basic and applied programs of research for these novel materials.
Download or read book Quasicrystals The State Of The Art written by David Divincenzo and published by World Scientific. This book was released on 1991-10-22 with total page 536 pages. Available in PDF, EPUB and Kindle. Book excerpt: This review volume provides the most up-to-date and authoritative description of research on icosahedral solids, which has advanced rapidly since the discovery of these unique materials in 1984. The present book, intended as a companion volume to the reprint volume on The Physics of Quasicrystals edited by P Steinhardt and S Ostlund, will be invaluable to graduate students and workers in the field as a comprehensive reference. Scientists in related fields can use it as a readable introduction to the important current problems in quasicrystals. The chapters have been written by many of the most prominent theorists and experimentalists on quasicrystals, both physicists and materials scientists, from around the world. Especially exciting are the details of the recent discovery of “perfect quasi-crystals”, new materials which promise to be an ideal form of quasiperiodic matter with little or no disorder. Other topics include: electron, X-ray and neutron quasi-crystallography, scanning tunneling microscopy studies, electronic transport experiments, quasicrystal faceting and statistical mechanics, growth rules and matching rules for quasicrystals, group theory and elasticity theory.
Download or read book Beyond Quasicrystals written by Francoise Axel and published by Springer Science & Business Media. This book was released on 2013-06-29 with total page 624 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is the collection of most of the written versions of the Courses given at the Winter School "Beyond Quasicrystals" in Les Houches (March 7-18, 1994). The School gathered lecturers and participants from all over the world and was prepared in the spirit of a general effort to promote theoretical and experimental interdisciplinary communication between mathematicians, theoretical and experimental physicists on the topic of the nature of geometric order in solids beyond standard periodicity and quasi periodicity. The overall structure of the book reflects the wish of the editors to pose this fundamental question of geometric order in solids from both the experimental and theoretical point of view. The first part is devoted more specifically to quasicrystals. These materials were the common starting point of most of the audience and present a first concrete example of a non-trivial geometric order. We chose to focus on a few fundamental aspects of quasicrystals related to hidden symmetries in solids which are not easily found in standard textbooks on the topic, not to reach an exhaustive survey which is already available elsewhere.
Download or read book Complex Metallic Alloys written by Jean-Marie Dubois and published by John Wiley & Sons. This book was released on 2010-12-13 with total page 428 pages. Available in PDF, EPUB and Kindle. Book excerpt: Covering fundamental research as well as real-world applications, this first book on CMAs at an introductory level treats everything from atomistic details to surface processing. Comprehensive, self-contained chapters provide readers with the latest knowledge on the most salient features of the topic, selected in terms of their relevance to potential technological applications. Edited by one of the most distinguished authorities on quasicrystals and this most important of their subclasses, the contributions elucidate aspects of CMAs from a particular viewpoint: physical and chemical characteristics in the sub-nanometer regime, mesoscale phenomena, preparation and processing of thin films, and large-scale engineering properties. The whole is rounded off by a look at the commercial potential of CMA-based applications. For PhD students and lecturers alike.
Download or read book Quasicrystals written by J.-B. Suck and published by Springer Science & Business Media. This book was released on 2013-04-17 with total page 575 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book provides an introduction to all aspects of the physics of quasicrystals. The chapters, each written by an expert in this field, cover quasiperiodic tilings and the modeling of the atomic structure of quasicrystals. The electronic density of states and the calculation of the electronic structure play a key role in this introduction, as does an extensive discussion of the atomic dynamics. The study of defects in quasicrystals by high resolution electron microscopy and the computer simulations of defects and fracture in decorated tilings are important subjects for the application of these aperiodic crystals.
Download or read book Dissertation Abstracts International written by and published by . This book was released on 2002 with total page 972 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 2001 with total page 776 pages. Available in PDF, EPUB and Kindle. Book excerpt:
