Physical Properties of Quasicrystals

ISBN-13: 9783540651888 / Angielski / Twarda / 1998 / 443 str.

Zbigniew M. Stadnik; Z. M. Stadnik; Zbigniew M. Stadnik

Opis

This book provides an up-to-date description of the unusual physical properties of quasicrystals. Emphasis is placed on the experimental results, which are compared with those of the corresponding crystalline and amorphous systems and discussed in terms of modern theoretical models.

Spis treści

1. Introduction.- References.- 2. Metallurgy of Quasicrystals.- 2.1 Introduction.- 2.2 Preparation of Quasicrystals.- 2.2.1 Rapid Solidification.- 2.2.2 Vapor Condensation.- 2.2.3 Mechanical Alloying.- 2.2.4 Crystallization of Melt-Quenched Amorphous Ribbons.- 2.2.5 Conventional Solidification.- 2.3 Structural Classification from Diffraction Patterns.- 2.3.1 Three-Dimensional Quasicrystals.- 2.3.2 Two-Dimensional Quasicrystals.- 2.3.3 One-Dimensional Quasicrystals.- 2.4 Quasicrystalline Alloy Systems and the Formation of Quasicrystals.- 2.4.1 Metastable Quasicrystals.- 2.4.2 Stable Quasicrystals.- 2.4.3 Quasicrystals as Hume-Rothery Phases.- 2.5 Phase Transformation from Amorphous to Icosahedral Phase.- 2.6 Phase Diagrams.- 2.6.1 Al-Li-Cu.- 2.6.2 Al-Cu-Fe.- 2.6.3 Al-Pd-Mn.- 2.6.4 Zn-Mg-Y.- 2.6.5 Al-Ni-Co.- 2.7 Growth of Quasicrystals.- 2.7.1 Morphologies of Quasicrystals.- 2.7.2 Solidification of Quasicrystals.- 2.7.3 Growing Large Single Grains.- 2.8 Summary.- References.- 3. Crystallography of Quasicrystals.- 3.1 Introduction.- 3.2 N-Dimensional Description of Quasicrystals.- 3.2.1 Embedding of Direct and Reciprocal Space.- 3.2.2 Structure Factor.- 3.3 One-Dimensional Quasicrystals.- 3.3.1 Indexing.- 3.3.2 Symmetry.- 3.3.3 Example of a One-Dimensional Quasicrystal:Fibonacci Phase.- 3.4 Decagonal Quasicrystals.- 3.4.1 Indexing.- 3.4.2 Symmetry.- 3.4.3 Example of a Decagonal Phase: Layers of Penrose Tilings.- 3.5 Icosahedral Quasicrystals.- 3.5.1 Indexing.- 3.5.2 Symmetry.- 3.5.3 Example of a Three-Dimensional Quasilattice:Ammann Tiling.- References.- 4. Experimental Determination of the Structure of Quasicrystals.- 4.1 Introduction.- 4.2 X-ray and Neutron Diffraction.- 4.2.1 Patterson Analysis.- 4.2.2 Contrast Variation.- 4.3 Structure of the Al-Pd-Mn Icosahedral Phase.- 4.3.1 Space Group Determination.- 4.3.2 Patterson Analysis.- 4.3.3 First-Order Model.- 4.3.4 About the Resulting Atomic Structure.- 4.3.5 Limitations of the Direct Approach.- 4.3.6 Modeling.- 4.4 Structure of the Al-Ni-Co Decagonal Quasicrystal.- 4.5 Conclusions.- References.- 5. Electronic Transport Properties of Quasicrystals — Experimental Results.- 5.1 Introduction.- 5.1.1 Background.- 5.1.2 Resistance Anomalies.- 5.1.3 Outline.- 5.2 Experimental Results.- 5.2.1 Overview.- 5.2.2 High-Temperature Electrical Resistivity.- 5.2.3 Hall Effect and Thermoelectric Power.- 5.2.4 Icosahedral Approximants.- 5.2.5 Decagonal Quasicrystals.- 5.3 Towards Understanding Transport Properties.- 5.3.1 Strong Sensitivity to Electron Concentration.- 5.3.2 Magnitude of the Electrical Resistivity.- 5.3.3 The Magnetoresistivity.- 5.3.4 ?(T) at Low and Intermediate Temperatures.- 5.3.5 Is There a Metal-Insulator Transition in Icosahedral Al-Pd-Re?.- 5.4 Concluding Remarks.- References.- 6. Theory of Electronic Structure in Quasicrystals.- 6.1 Introduction.- 6.2 Electronic Structure in One-and Two-Dimensional Quasilattices.- 6.2.1 One-Dimensional Quasilattice: Fibonacci Lattice.- 6.2.2 Two-Dimensional Quasilattice: Penrose Lattice.- 6.3 Electronic Structure in Quasicrystals.- 6.3.1 Method of Calculations: Tight-Binding LMTO and Related Methods.- 6.3.2 Quasi-Brillouin Zone and Modification of DOS of Model Icosahedral Al.- 6.3.3 Electronic Structure in MI-Type Icosahedral Quasicrystals.- 6.3.4 Electronic Structure in TC-Type Icosahedral Quasicrystals.- 6.3.5 Electronic Structure in Decagonal Quasicrystals.- 6.3.6 General Characteristics of DOS and Wave Functions.- 6.3.7 Experimental Study of Electronic Structures.- 6.4 Transport Properties in Quasicrystals.- 6.4.1 Scenario of Transport in Random Systems.- 6.4.2 Experimental Observations.- 6.4.3 Effects of Randomness.- 6.4.4 Boltzmann Theory and Relaxation-Time Approximation.- 6.4.5 Anomalous Diffusion.- 6.4.6 Scaling Behavior.- 6.4.7 Scenario of Transport in Quasicrystals.- 6.5 Summary.- References.- 7. Elementary Excitations and Physical Properties.- 7.1 Introduction.- 7.1.1 Quasiperiodic Structure.- 7.1.2 Physical Properties.- 7.1.3 Spectral Properties of Quasiperiodic Hamiltonians.- 7.2 Quasiperiodicity, Symmetry, and Elementary Excitations.- 7.3 Modelling Quasicrystalline Structures and Approximant Phases.- 7.3.1 Icosahedral Quasicrystals.- 7.3.2 Decagonal Quasicrystals.- 7.3.3 Approximant Structures.- 7.4 Numerical Characterization of Elementary Excitations.- 7.4.1 Direct Diagonalization.- 7.4.2 Real-Space Recursion.- 7.4.3 Comparison With Experiment.- 7.5 Phonons in Quasicrystals.- 7.5.1 Interactomic Force Law and Quasiperiodicity — Modulated Quasicrystals.- 7.5.2 Phonons in Icosahedral Quasicrystals.- 7.5.3 Phonons in Decagonal Quasicrystals.- 7.5.4 Phonons — Summary.- 7.6 Electrons in Quasicrystals.- 7.6.1 s,p-Bonded Icosahedral Alloys as Hume-Rothery Phases.- 7.6.2 Icosahedral and Decagonal Aluminum-Transition Metal Alloys.- 7.6.3 Titanium-Based Quasicrystals.- 7.6.4 Fine Structure of the Electronic Spectrum, Pseudogaps, and Real Gaps.- 7.6.5 Band-Structure Effects in Electronic Transport.- 7.6.6 Magnetic Properties of Quasicrystals.- 7.6.7 Electrons — A Summary.- 7.7 Final Remarks.- References.- 8. Spectroscopic Studies of the Electronic Structure.- 8.1 Introduction.- 8.2 Theoretical Predictions.- 8.2.1 Pseudogap in the Density of States.- 8.2.2 Fine Strucure of the Density of States.- 8.3 Experimental Results.- 8.3.1 s,p-Bonded Icosahedral Alloys.- 8.3.2 Al-Cu-Transition Metal Icosahedral Alloys.- 8.3.3 Al-Pd-Mn Icosahedral Alloys.- 8.3.4 Al-Pd-Re Icosahedral Alloys.- 8.3.5 Al-Co-Cu Decagonal Alloys.- 8.3.6 Al-Ni-Co and Al-Ni-Rh Decagonal Alloys.- 8.3.7 Fine Structure of the Density of States.- 8.4 Uniqueness of the Electronic Structure of Quasicrystals.- 8.5 Quasiperiodicity and Unusual Physical Properties.- 8.6 Conclusions and Outlook.- References.- 9. Magnetic Properties of Quasicrystals.- 9.1 Introduction.- 9.2 Al-Based Quasicrystals.- 9.2.1 Paramagnetism, Effective Magnetic Moment and Saturation Magnetization.- 9.2.2 Fraction of Magnetic Mn Atoms and Giant Magnetic Moment.- 9.2.3 Difference Between Magnetic Moments in Icosahedral and Decagonal Phases.- 9.2.4 Spin-Glass Behavior.- 9.2.5 Low-Temperature Specific Heat.- 9.2.6 Model for Magnetism and Pauling Valence.- 9.2.7 Phasons, Diamagnetism, and Pauli Paramagnetism.- 9.2.8 Ferromagnetism.- 9.3 Mg-RE-Zn Quasicrystals.- 9.3.1 Susceptibility and Spin-Glass Behavior.- 9.3.2 Low-Temperature Specific Heat.- 9.3.3 Antiferromagnetism.- 9.4 Summary.- References.- 10. Surface Science of Quasicrystals.- 10.1 Introduction.- 10.1.1 Background.- 10.1.2 Outline.- 10.2 Oxidized Surfaces.- 10.2.1 Overview.- 10.2.2 Oxide Composition.- 10.2.3 Oxide Depth.- 10.2.4 Comparison to Crystalline Materials.- 10.2.5 Oxide Structure.- 10.2.6 Oxidation-Induced Phase Transformations.- 10.3 Surface Energies.- 10.4 Clean Surfaces.- 10.4.1 Methods of Clean Surface Preparation.- 10.4.2 Surface Composition.- 10.4.3 Surface Structure and Topography.- 10.4.4 Surface Chemistry.- 10.5 Friction.- 10.6 Concluding Remarks.- References.- 11. Mechanical Properties of Quasicrystals.- 11.1 Introduction.- 11.2 Low-Temperature Mechanical Properties.- 11.2.1 Mechanical Property Data.- 11.2.2 Fracture.- 11.3 Dislocations in Quasicrystals.- 11.3.1 Background.- 11.3.2 Dislocations in a Quasilattice.- 11.3.3 Dislocation Analysis.- 11.4 High-Temperature Plastic Deformation.- 11.4.1 Background.- 11.4.2 Theoretical.- 11.4.3 Results of Mechanical Testing.- 11.4.4 Microscopic Observations.- 11.5 Discussion.- 11.5.1 Model of Dislocation Friction in Quasicrystals.- 11.6 Concluding Remarks.- References.- 12. Toward Industrial Applications.- 12.1 Introduction.- 12.2 The Relevant Properties of Quasicrystals.- 12.2.1 Electronic Structure and Transport.- 12.2.2 Visible and Infrared Optical Properties.- 12.2.3 Thermopower.- 12.2.4 Lattice Dynamics.- 12.2.5 Ductility.- 12.2.6 Surface Properties.- 12.2.7 Corrosion Resistance.- 12.2.8 Hydrogen Storage.- 12.3 Possible Applications.- 12.3.1 Coatings.- 12.3.2 Dispersion Hardening of Crystalline, Quasicrystalline, and Amorphous Alloys.- 12.3.3 Selective Absorbers for Solar-Thermal Converters.- 12.3.4 Thermoelectric Devices.- 12.3.5 Hydrogen Storage and Battery Applications.- 12.4 Conclusion.- References.

Blurb

Physical Properties of Quasicrystals presents an up-to-date introduction to the field of quasicrystals, a new form of matter which was discovered only in 1984. The field is inspected from an experimental point of view and the results are interpreted within the framework of the existing theoretical models. The book discusses our current understanding of the unusual physical properties of quasicrystals, as well as highlighting the challenges associated with the physical interpretation of the properties of these complex and fascinating materials. The book is written by a team of active researchers and conveys the sense of an excitement associated with research in a rapidly developing area of new alloys. A wealth of measured experimental data is presented and important information is given in a convenient tabular form. Although the book is aimed at a broad audience interested in the intriguing physical properties of these novel alloys, it will be of general use both to long-time workers in the field and uninitiated graduate students.