Solid StateChemiStryand itS appliCationSS e c o n d e d i t i o n Student edition

Anthony R. West

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Solid State Chemistryand its Applications

Second Edition

Solid State Chemistryand its Applications

Second Edition

Student Edition

ANTHONY R. WESTDepartment of Materials Science and Engineering,

University of Sheffield, UK

This edition first published 2014© 2014 John Wiley & Sons, Ltd

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Library of Congress Cataloging-in-Publication Data

West, Anthony R.Solid state chemistry and its applications / Anthony R. West. – Second edition, student edition.

pages cmIncludes index.ISBN 978-1-119-94294-8 (pbk.)

1. Solid state chemistry. I. Title.QD478.W47 2014541′.0421–dc23

2013029528

A catalogue record for this book is available from the British Library.

ISBN: 9781119942948

Cover images created using CrystalMaker R© software. CrystalMaker Software Ltd, www.crystalmaker.com

Set in 10/12pt Times by Aptara Inc., New Delhi, India

1 2014

For Sheena, Isla, Graeme, Jenny and Susie

Contents

Preface xvii

Chemistry – Solid State Chemistry – Materials Chemistry – Materials Science and Engineering xix

Companion Website xxiiiCrystalViewer xxiiiCrystal Structure Library xxiv

Biography xxv

1 Crystal Structures and Crystal Chemistry 11.1 Unit Cells and Crystal Systems 11.2 Symmetry 3

1.2.1 Rotational Symmetry; Symmetry Elements and Operations 31.2.2 Quasicrystals 61.2.3 Mirror Symmetry 61.2.4 Centre of Symmetry and Inversion Axes 61.2.5 Point Symmetry and Space Symmetry 9

1.3 Symmetry and Choice of Unit Cell 101.4 Lattice, Bravais Lattice 111.5 Lattice Planes and Miller Indices 141.6 Indices of Directions 161.7 d-Spacing Formulae 171.8 Crystal Densities and Unit Cell Contents 171.9 Description of Crystal Structures 181.10 Close Packed Structures – Cubic and Hexagonal Close Packing 191.11 Relationship between Cubic Close Packed and Face Centred Cubic 211.12 Hexagonal Unit Cell and Close Packing 211.13 Density of Close Packed Structures 221.14 Unit Cell Projections and Atomic Coordinates 241.15 Materials That Can Be Described as Close Packed 25

1.15.1 Metals 251.15.2 Alloys 251.15.3 Ionic Structures 26

Contents viii

1.15.3.1 Tetrahedral and Octahedral Sites 261.15.3.2 Relative Sizes of Tetrahedral and Octahedral Sites 281.15.3.3 Location of Tetrahedral and Octahedral Sites in an fcc Unit Cell;

Bond Length Calculations 291.15.3.4 Description of Crystal Structures; Fractional Atomic Coordinates 30

1.15.4 Covalent Network Structures 311.15.5 Molecular Structures 311.15.6 Fullerenes and Fullerides 31

1.16 Structures Built of Space-Filling Polyhedra 331.17 Some Important Structure Types 35

1.17.1 Rock Salt (NaCl), Zinc Blende or Sphalerite (ZnS), Fluorite (CaF2),Antifluorite (Na2O) 351.17.1.1 Rock Salt Structure 371.17.1.2 Zinc Blende (Sphalerite) Structure 381.17.1.3 Antifluorite/Fluorite Structure 391.17.1.4 Bond Length Calculations 41

1.17.2 Diamond 421.17.3 Wurtzite (ZnS) and Nickel Arsenide (NiAs) 431.17.4 Caesium Chloride (CsCl) 471.17.5 Other AX Structures 481.17.6 Rutile (TiO2), Cadmium Iodide (CdI2), Cadmium Chloride (CdCl2) and

Caesium Oxide (Cs2O) 491.17.7 Perovskite (SrTiO3) 54

1.17.7.1 Tolerance Factor 571.17.7.2 BaTiO3 571.17.7.3 Tilted Perovskites: Glazer Notation 581.17.7.4 CaCu3Ti4O12, CCTO 621.17.7.5 Anion-Deficient Perovskites 621.17.7.6 Stoichiometry–Property Relations 62

1.17.8 Rhenium Trioxide (ReO3), Perovskite Tungsten Bronzes, Tetragonal TungstenBronzes and Tunnel Structures 63

1.17.9 Spinel 661.17.10 Olivine 701.17.11 Corundum, Ilmenite and LiNbO3 721.17.12 Fluorite-Related Structures and Pyrochlore 721.17.13 Garnet 751.17.14 Perovskite-Rock Salt Intergrowth Structures: K2NiF4, Ruddlesden–Popper

Phases and Layered Cuprate Superconductors 761.17.15 The Aluminium Diboride Structure (AlB2) 801.17.16 Silicate Structures – Some Tips to Understanding Them 81

2 Crystal Defects, Non-Stoichiometry and Solid Solutions 832.1 Perfect and Imperfect Crystals 832.2 Types of Defect: Point Defects 84

2.2.1 Schottky Defect 852.2.2 Frenkel Defect 85

2.2.2.1 The Kroger–Vink Notation for Crystal Defects 862.2.2.2 Thermodynamics of Schottky and Frenkel Defect Formation 87

ix Contents

2.2.3 Colour Centres 902.2.4 Vacancies and Interstitials in Non-Stoichiometric Crystals: Extrinsic and

Intrinsic Defects 912.2.5 Defect Clusters or Aggregates 922.2.6 Interchanged Atoms: Order–Disorder Phenomena 95

2.3 Solid Solutions 952.3.1 Substitutional Solid Solutions 962.3.2 Interstitial Solid Solutions 982.3.3 More Complex Solid Solution Mechanisms: Aliovalent Substitution 99

2.3.3.1 Ionic Compensation Mechanisms 992.3.3.2 Electronic Compensation: Metals, Semi- and Superconductors 102

2.3.4 Thermodynamically Stable and Metastable Solid Solutions 1042.3.5 Experimental Methods for Studying Solid Solutions 104

2.3.5.1 X-ray Powder Diffraction, XRD 1042.3.5.2 Density Measurements 1052.3.5.3 Changes in Other Properties – Thermal Activity and DTA/DSC 107

2.4 Extended Defects 1082.4.1 Crystallographic Shear Structures 1082.4.2 Stacking Faults 1102.4.3 Subgrain Boundaries and Antiphase Domains (Boundaries) 110

2.5 Dislocations and Mechanical Properties of Solids 1112.5.1 Edge Dislocations 1122.5.2 Screw Dislocations 1142.5.3 Dislocation Loops 1152.5.4 Dislocations and Crystal Structure 1172.5.5 Mechanical Properties of Metals 1182.5.6 Dislocations, Vacancies and Stacking Faults 1202.5.7 Dislocations and Grain Boundaries 122

3 Bonding in Solids 1253.1 Overview: Ionic, Covalent, Metallic, van der Waals and Hydrogen Bonding

in Solids 1253.2 Ionic Bonding 126

3.2.1 Ions and Ionic Radii 1263.2.2 Ionic Structures – General Principles 1303.2.3 The Radius Ratio Rules 1333.2.4 Borderline Radius Ratios and Distorted Structures 1353.2.5 Lattice Energy of Ionic Crystals 1363.2.6 Kapustinskii’s Equation 1403.2.7 The Born–Haber Cycle and Thermochemical Calculations 1413.2.8 Stabilities of Real and Hypothetical Ionic Compounds 143

3.2.8.1 Inert Gas Compounds 1433.2.8.2 Lower and Higher Valence Compounds 144

3.2.9 Effect of Partial Covalent Bonding on Crystal Structures 1453.2.10 Effective Nuclear Charge 1473.2.11 Electronegativity and Partially Charged Atoms 1473.2.12 Coordinated Polymeric Structures – Sanderson’s Model 1493.2.13 Mooser–Pearson Plots and Ionicities 150

Contents x

3.2.14 Bond Valence and Bond Length 1513.2.15 Non-Bonding Electron Effects 153

3.2.15.1 d-Electron Effects 1533.2.15.2 Inert Pair Effect 161

3.3 Covalent Bonding 1613.3.1 Particle-Wave Duality, Atomic Orbitals, Wavefunctions and Nodes 1623.3.2 Orbital Overlap, Symmetry and Molecular Orbitals 1633.3.3 Valence Bond Theory, Electron Pair Repulsion, Hybridisation and

Oxidation States 1693.4 Metallic Bonding and Band Theory 173

3.4.1 Band Structure of Metals 1793.4.2 Band Structure of Insulators 1793.4.3 Band Structure of Semiconductors: Silicon 1793.4.4 Band Structure of Inorganic Solids 181

3.4.4.1 III–V, II–VI and I–VII Compounds 1813.4.4.2 Transition Metal Compounds 1823.4.4.3 Fullerenes and Graphite 184

3.5 Bands or Bonds: a Final Comment 185

4 Synthesis, Processing and Fabrication Methods 1874.1 General Observations 1874.2 Solid State Reaction or Shake ’n Bake Methods 187

4.2.1 Nucleation and Growth, Epitaxy and Topotaxy 1884.2.2 Practical Considerations and Some Examples of Solid State Reactions 191

4.2.2.1 Li4SiO4 1934.2.2.2 YBa2Cu3O7–δ 1934.2.2.3 Na β/β ′′ alumina 193

4.2.3 Combustion Synthesis 1944.2.4 Mechanosynthesis 195

4.3 Low Temperature or Chimie Douce Methods 1964.3.1 Alkoxide Sol–Gel Method 196

4.3.1.1 Synthesis of MgAl2O4 1974.3.1.2 Synthesis of Silica Glass 1974.3.1.3 Spinning of Alumina Fibres 1974.3.1.4 Preparation of Indium Tin Oxide (ITO) and Other Coatings 1984.3.1.5 Fabrication of YSZ Ceramics 198

4.3.2 Sol–Gel Method Using Oxyhydroxides and Colloid Chemistry 1984.3.2.1 Synthesis of Zeolites 1994.3.2.2 Preparation of Alumina-Based Abrasives and Films 200

4.3.3 Citrate Gel and Pechini Processes 2004.3.4 Use of Homogeneous, Single-Source Precursors 2014.3.5 Hydrothermal and Solvothermal Synthesis 2024.3.6 Microwave Synthesis 2044.3.7 Intercalation and Deintercalation 205

4.3.7.1 Graphite Intercalation Compounds 2074.3.7.2 Pillared Clays and Layered Double Hydroxides 2084.3.7.3 Synthesis of Graphene 209

xi Contents

4.3.8 Example of a Difficult Synthesis Made Possible by Chimie DouceMethods: BiFeO3 211

4.3.9 Molten Salt Synthesis, MSS 2124.4 Gas-Phase Methods 213

4.4.1 Vapour-Phase Transport 2134.4.2 Chemical Vapour Deposition, CVD 216

4.4.2.1 Amorphous Silicon 2174.4.2.2 Diamond Films 219

4.4.3 Sputtering and Evaporation 2214.4.4 Atomic Layer Deposition, ALD 2224.4.5 Aerosol Synthesis and Spray Pyrolysis 223

4.5 High-Pressure Methods 2254.6 Crystal Growth 226

4.6.1 Czochralski Method 2264.6.2 Bridgman and Stockbarger Methods 2264.6.3 Zone Melting 2274.6.4 Precipitation from Solution or Melt: Flux Method 2274.6.5 Verneuil Flame Fusion Method 228

5 Crystallography and Diffraction Techniques 2295.1 General Comments: Molecular and Non-Molecular Solids 229

5.1.1 Identification of Crystalline Solids 2295.1.2 Structure of Non-Molecular Crystalline Solids 2295.1.3 Defects, Impurities and Stoichiometry of Crystalline Solids 230

5.2 Characterisation of Solids 2315.3 X-Ray Diffraction 232

5.3.1 Generation of X-Rays 2325.3.1.1 Laboratory Sources Utilising Inner Shell Electronic Transitions 2325.3.1.2 Synchrotron X-ray Sources 235

5.3.2 Interaction of X-Rays with Matter 2355.3.3 Optical Grating and Diffraction of Light 2365.3.4 Crystals and Diffraction of X-Rays 238

5.3.4.1 The Laue Equations 2385.3.4.2 Bragg’s Law 239

5.3.5 X-Ray Diffraction Methods 2405.3.6 The Powder Method – Principles and Uses 240

5.3.6.1 Focusing of X-rays: Theorem of a Circle 2435.3.6.2 Crystal Monochromators 2445.3.6.3 Powder Diffractometers 2445.3.6.4 Guinier Focusing Cameras 2455.3.6.5 A Powder Pattern of a Crystalline Phase is its ‘Fingerprint’ 2465.3.6.6 Powder Patterns and Crystal Structures 247

5.3.7 Intensities 2485.3.7.1 Scattering of X-rays by an Atom: Atomic Scattering Factors or Form

Factors 2495.3.7.2 Scattering of X-rays by a Crystal – Systematic Absences 2505.3.7.3 General Equation for Phase Difference, δ 253

Contents xii

5.3.7.4 Intensities and Structure Factors 2555.3.7.5 Temperature Factors 2585.3.7.6 R-Factors and Structure Determination 2595.3.7.7 Structure Refinement from Powder Data: Rietveld Refinement 259

5.3.8 X-Ray Crystallography and Structure Determination – What is Involved? 2605.3.8.1 The Patterson Method 2635.3.8.2 Fourier Methods 2645.3.8.3 Direct Methods 2645.3.8.4 Electron Density Maps 265

5.4 Electron Diffraction 2655.5 Neutron Diffraction 266

5.5.1 Crystal Structure Determination 2675.5.2 Magnetic Structure Analysis 2685.5.3 Inelastic Scattering, Soft Modes and Phase Transitions 269

6 Other Techniques: Microscopy, Spectroscopy, Thermal Analysis 2716.1 Diffraction and Microscopic Techniques: What Do They Have in Common? 2716.2 Optical and Electron Microscopy Techniques 272

6.2.1 Optical Microscopy 2726.2.1.1 Polarising Microscope 2736.2.1.2 Reflected Light Microscope 276

6.2.2 Electron Microscopy 2766.2.2.1 Scanning Electron Microscopy 2806.2.2.2 Electron Probe Microanalysis, EPMA, and Energy-Dispersive X-ray

Spectroscopy, EDS or EDX 2816.2.2.3 Auger Electron (Emission) Microscopy and Spectroscopy, AES 2826.2.2.4 Cathodoluminescence, CL 2846.2.2.5 Transmission Electron Microscopy, TEM, and Scanning

Transmission Electron Microscopy, STEM 2876.2.2.6 Electron Energy Loss Spectroscopy, EELS 2886.2.2.7 High-Angle Annular Dark Field, HAADF/Z-Contrast STEM 289

6.3 Spectroscopic Techniques 2916.3.1 Vibrational Spectroscopy: IR and Raman 2936.3.2 Visible and Ultraviolet (UV) Spectroscopy 2966.3.3 Nuclear Magnetic Resonance (NMR) Spectroscopy 2986.3.4 Electron Spin Resonance (ESR) Spectroscopy 3016.3.5 X-Ray Spectroscopies: XRF, AEFS, EXAFS 303

6.3.5.1 Emission Techniques 3036.3.5.2 Absorption Techniques 305

6.3.6 Electron Spectroscopies: ESCA, XPS, UPS, AES, EELS 3086.3.7 Mossbauer Spectroscopy 312

6.4 Thermal Analysis (TA) 3146.4.1 Thermogravimetry (TG) 3156.4.2 Differential Thermal Analysis (DTA) and Differential Scanning

Calorimetry (DSC) 3156.4.3 Applications 317

6.5 Strategy to Identify, Analyse and Characterise ‘Unknown’ Solids 321

xiii Contents

7 Phase Diagrams and their Interpretation 3257.1 The Phase Rule, the Condensed Phase Rule and Some Definitions 3257.2 One-Component Systems 330

7.2.1 The System H2O 3317.2.2 The System SiO2 3327.2.3 Condensed One-Component Systems 333

7.3 Two-Component Condensed Systems 3337.3.1 A Simple Eutectic System 333

7.3.1.1 Liquidus and Solidus 3357.3.1.2 Eutectic 3357.3.1.3 Lever Rule 3357.3.1.4 Eutectic Reaction 3367.3.1.5 The Liquidus, Saturation Solubilities and Freezing Point Depression 337

7.3.2 Binary Systems with Compounds 3377.3.2.1 Congruent Melting 3377.3.2.2 Incongruent Melting, Peritectic Point, Peritectic Reaction 3377.3.2.3 Non-Equilibrium Effects 3397.3.2.4 Upper and Lower Limits of Stability 340

7.3.3 Binary Systems with Solid Solutions 3407.3.3.1 Complete Solid Solution 3407.3.3.2 Fractional Crystallisation 3417.3.3.3 Thermal Maxima and Minima 3427.3.3.4 Partial Solid Solution Systems 342

7.3.4 Binary Systems with Solid–Solid Phase Transitions 3447.3.5 Binary Systems with Phase Transitions and Solid Solutions: Eutectoids

and Peritectoids 3457.3.6 Binary Systems with Liquid Immiscibility: MgO–SiO2 3477.3.7 Some Technologically Important Phase Diagrams 348

7.3.7.1 The System Fe–C: Iron and Steel Making 3487.3.7.2 The System CaO–SiO2: Cement Manufacture 3497.3.7.3 The System Na–S: Na/S Batteries 3507.3.7.4 The System Na2O–SiO2: Glass Making 3517.3.7.5 The System Li2O–SiO2: Metastable Phase Separation and Synthetic

Opals 3527.3.7.6 Purification of Semiconducting Si by Zone Refining 3537.3.7.7 The System ZrO2–Y2O3: Yttria-Stabilised Zirconia, YSZ, Solid

Electrolyte 3547.3.7.8 The System Bi2O3–Fe2O3: Multiferroic BiFeO3 354

7.4 Some Tips and Guidelines for Constructing Binary Phase Diagrams 355

8 Electrical Properties 3598.1 Survey of Electrical Properties and Electrical Materials 3598.2 Metallic Conductivity 361

8.2.1 Organic Metals: Conjugated Systems 3628.2.1.1 Polyacetylene 3628.2.1.2 Poly-p-Phenylene and Polypyrrole 364

8.2.2 Organic Metals: Charge-Transfer Complexes 365