Physics and Chemistry of Nanosolids

Frank J. Owens, PhD, is a Senior Research Scientist of the U.S. Army's Armament Research, Development, and Engineering Center, and a Professor of Physics in the graduate school of Hunter College of the City University of New York.Charles P. Poole Jr., PhD, is Professor Emeritus in the Department of Physics and Astronomy at the University of South Carolina and is a member of the USC Nanotechnology Center. Both authors are Fellows of the American Physical Society.

• Preface xv1. Physics of Bulk Solids 11.1 Structure 11.1.1 Size Dependence of Properties 11.1.2 Crystal Structures 21.1.3 Face-Centered Cubic Nanoparticles 71.1.4 Large Face-Centered Cubic Nanoparticles 91.1.5 Tetrahedrally Bonded Semiconductor Structures 101.1.6 Lattice Vibrations 141.2 Surfaces of Crystals 161.2.1 Surface Characteristics 161.2.2 Surface Energy 171.2.3 Face-Centered Cubic Surface Layers 181.2.4 Surfaces of Zinc Blende and Diamond Structures 211.2.5 Adsorption of Gases 231.2.6 Electronic Structure of a Surface 251.2.7 Surface Quantum Well 261.3 Energy Bands 261.3.1 Insulators, Semiconductors, and Conductors 261.3.2 Reciprocal Space 271.3.3 Energy Bands and Gaps of Semiconductors 281.3.4 Effective Mass 341.3.5 Fermi Surfaces 351.4 Localized Particles 361.4.1 Donors, Acceptors, and Deep Traps 361.4.2 Mobility 371.4.3 Excitons 38Problems 40References 412. Methods of Measuring Properties of Nanostructures 432.1 Introduction 432.2 Structure 442.2.1 Atomic Structures 442.2.2 Crystallography 452.2.3 Particle Size Determination 502.2.4 Surface Structure 542.3 Microscopy 542.3.1 Transmission Electron Microscopy 542.3.2 Field Ion Microscopy 592.3.3 Scanning Microscopy 592.4 Spectroscopy 662.4.1 Infrared and Raman Spectroscopy 662.4.2 Photoemission, X-Ray, and Auger Spectroscopy 722.4.3 Magnetic Resonance 782.5 Various Bulk Properties 812.5.1 Mechanical Properties 812.5.2 Electrical Properties 812.5.3 Magnetic Properties 822.5.4 Other Properties 82Problems 82References 833. Properties of Individual Nanoparticles 853.1 Introduction 853.2 Metal Nanoclusters 863.2.1 Magic Numbers 863.2.2 Theoretical Modeling of Nanoparticles 883.2.3 Geometric Structure 913.2.4 Electronic Structure 943.2.5 Reactivity 973.2.6 Fluctuations 1003.2.7 Magnetic Clusters 1003.2.8 Bulk-to-Nano Transition 1033.3 Semiconducting Nanoparticles 1043.3.1 Optical Properties 1043.3.2 Photofragmentation 1063.3.3 Coulomb Explosion 1073.4 Rare-Gas and Molecular Clusters 1073.4.1 Inert-Gas Clusters 1073.4.2 Superfluid Clusters 1083.4.3 Molecular Clusters 1093.4.4 Nanosized Organic Crystals 1113.5 Methods of Synthesis 1113.5.1 RF Plasma 1113.5.2 Chemical Methods 1113.5.3 Thermolysis 1123.5.4 Pulsed-Laser Methods 1143.5.5 Synthesis of Nanosized Organic Crystals 1143.6 Summary 118Problems 1184. The Chemistry of Nanostructures 1214.1 Chemical Synthesis of Nanostructures 1214.1.1 Solution Synthesis 1214.1.2 Capped Nanoclusters 1224.1.3 Solgel Processing 1244.1.4 Electrochemical Synthesis of Nanostructures 1254.2 Reactivity of Nanostructures 1254.3 Catalysis 1274.3.1 Nature of Catalysis 1274.3.2 Surface Area of Nanoparticles 1274.3.3 Porous Materials 1314.4 Self-Assembly 1354.4.1 The Self-Assembly Process 1354.4.2 Semiconductor Islands 1364.4.3 Monolayers 139Problems 1415. Polymer and Biological Nanostructures 1435.1 Polymers 1435.1.1 Polymer Structure 1435.1.2 Sizes of Polymers 1465.1.3 Nanocrystals of Polymers 1485.1.4 Conductive Polymers 1515.1.5 Block Copolymers 1525.2 Biological Nanostructures 1545.2.1 Sizes of Biological Nanostructures 1545.2.2 Polypeptide Nanowire and Protein Nanoparticles 1605.2.3 Nucleic Acids 1625.2.3.1 DNA Double Nanowire 1625.2.3.2 Genetic Code and Protein Synthesis 1665.2.3.3 Proteins 1675.2.3.4 Micelles and Vesicles 1695.2.3.5 Multilayer Films 172Problems 174References 1746. Cohesive Energy 1776.1 Ionic Solids 1776.2 Defects in Ionic Solids 1836.3 Covalently Bonded Solids 1856.4 Organic Crystals 1866.5 Inert-Gas Solids 1906.6 Metals 1916.7 Conclusion 193Problems 1937. Vibrational Properties 1957.1 The Finite One-Dimensional Monatomic Lattice 1957.2 Ionic Solids 1977.3 Experimental Observations 1997.3.1 Optical and Acoustical Modes 1997.3.2 Vibrational Spectroscopy of Surface Layers of Nanoparticles 2017.3.2.1 Raman Spectroscopy of Surface Layers 2017.3.2.2 Infrared Spectroscopy of Surface Layers 2017.4 Phonon Confinement 2077.5 Effect of Dimension on Lattice Vibrations 2097.6 Effect of Dimension on Vibrational Density of States 2117.7 Effect of Size on Debye Frequency 2157.8 Melting Temperature 2167.9 Specific Heat 2187.10 Plasmons 2207.11 Surface-Enhanced Raman Spectroscopy 2227.12 Phase Transitions 223Problems 226References 2278. Electronic Properties 2298.1 Ionic Solids 2298.2 Covalently Bonded Solids 2328.3 Metals 2348.3.1 Effect of Lattice Parameter on Electronic Structure 2358.3.2 Free-Electron Model 2358.3.3 The Tight-Binding Model 2398.4 Measurements of Electronic Structure of Nanoparticles 2428.4.1 Semiconducting Nanoparticles 2428.4.2 Organic Solids 2488.4.3 Metals 250Problems 2519. Quantum Wells, Wires, and Dots 2539.1 Introduction 2539.2 Fabricating Quantum Nanostructures 2539.2.1 Solution Fabrication 2549.2.2 Lithography 2579.3 Size and Dimensionality Effects 2619.3.1 Size Effects 2619.3.2 Size Effects on Conduction Electrons 2639.3.3 Conduction Electrons and Dimensionality 2649.3.4 Fermi Gas and Density of States 2659.3.5 Potential Wells 2689.3.6 Partial Confinement 2729.3.7 Properties Dependent on Density of States 2739.4 Excitons 2759.5 Single-Electron Tunneling 2769.6 Applications 2809.6.1 Infrared Detectors 2809.6.2 Quantum Dot Lasers 280Problems 285References 28510. Carbon Nanostructures 28710.1 Introduction 28710.2 Carbon Molecules 28710.2.1 Nature of the Carbon Bond 28710.2.2 New Carbon Structures 28910.3 Carbon Clusters 28910.3.1 Small Carbon Clusters 28910.3.2 Buckyball 29210.3.3 The Structure of Molecular C60 29310.3.4 Crystalline C60 29610.3.5 Larger and Smaller Buckyballs 30010.3.6 Buckyballs of Other Atoms 30010.4 Carbon Nanotubes 30110.4.1 Fabrication 30110.4.2 Structure 30410.4.3 Electronic Properties 30610.4.4 Vibrational Properties 31210.4.5 Functionalization 31410.4.6 Doped Carbon Nanotubes 32210.4.7 Mechanical Properties 32510.5 Nanotube Composites 32710.5.1 Polymer–Carbon Nanotube Composites 32710.5.2 Metal–Carbon Nanotube Composites 32910.6 Graphene Nanostructures 330Problems 33511. Bulk Nanostructured Materials 33711.1 Solid Methods for Preparation of Disordered Nanostructures 33711.1.1 Methods of Synthesis 33711.1.2 Metal Nanocluster Composite Glasses 34011.1.3 Porous Silicon 34311.2 Nanocomposites 34711.2.1 Layered Nanocomposites 34711.2.2 Nanowire Composites 34911.2.3 Composites of Nanoparticles 35011.3 Nanostructured Crystals 35111.3.1 Natural Nanocrystals 35111.3.2 Crystals of Metal Nanoparticles 35211.3.3 Arrays of Nanoparticles in Zeolites 35511.3.4 Nanoparticle Lattices in Colloidal Suspensions 35711.3.5 Computational Prediction of Cluster Lattices 35811.4 Electrical Conduction in Bulk Nanostructured Materials 35911.4.1 Bulk Materials Consisting of Nanosized Grains 35911.4.2 Nanometer-Thick Amorphous Films 36411.5 Other Properties 364Problems 36512. Mechanical Properties of Nanostructured Materials 36712.1 Stress–Strain Behavior of Materials 36712.2 Failure Mechanisms of Conventional Grain-Sized Materials 37012.3 Mechanical Properties of Consolidated Nano-Grained Materials 37112.4 Nanostructured Multilayers 37412.5 Mechanical and Dynamical Properties of Nanosized Devices 37612.5.1 General Considerations 37612.5.2 Nanopendulum 37812.5.3 Vibrations of a Nanometer String 38012.5.4 The Nanospring 38112.5.5 The Clamped Beam 38212.5.6 The Challenges and Possibilities of Nanomechanical Sensors 38512.5.7 Methods of Fabrication of Nanosized Devices 387Problems 39013. Magnetism in Nanostructures 39313.1 Basics of Ferromagnetism 39313.2 Behavior of Powders of Ferromagnetic Nanoparticles 39813.2.1 Properties of a Single Ferromagnetic Nanoparticle 39813.2.2 Dynamics of Individual Magnetic Nanoparticles 40013.2.3 Measurements of Superparamagnetism and the Blocking Temperature 40213.2.4 Nanopore Containment of Magnetic Particles 40513.3 Ferrofluids 40613.4 Bulk Nanostructured Magnetic Materials 41313.4.1 Effect of Nanosized Grain Structure on Magnetic Properties 41313.4.2 Magnetoresistive Materials 41613.4.3 Carbon Nanostructured Ferromagnets 42413.5 Antiferromagnetic Nanoparticles 429Problems 43014. Nanoelectronics, Spintronics, Molecular Electronics, and Photonics 43314.1 Nanoelectronics 43314.1.1 N and P Doping and PN Junctions 43314.1.2 MOSFET 43514.1.3 Scaling of MOSFETs 43614.2 Spintronics 44014.2.1 Definition and Examples of Spintronic Devices 44014.2.2 Magnetic Storage and Spin Valves 44014.2.3 Dilute Magnetic Semiconductors 44514.3 Molecular Switches and Electronics 44914.3.1 Molecular Switches 44914.3.2 Molecular Electronics 45314.3.3 Mechanism of Conduction through a Molecule 45814.4 Photonic Crystals 459Problems 465Reference 46615. Superconductivity in Nanomaterials 46715.1 Introduction 46715.2 Zero Resistance 46715.2.1 The Superconducting Gap 46915.2.2 Cooper Pairs 47015.3 The Meissner Effect 47215.3.1 Magnetic Field Exclusion 47215.3.2 Type I and Type II Superconductors 47415.4 Properties of Flux 47815.4.1 Quantization of Flux 47815.4.2 Vortex Configurations 47915.4.3 Flux Creep and Flux Flow 48015.4.4 Vortex Pinning 48415.5 Dependence of Superconducting Properties on Size Effects 48415.6 Resistivity and Sheet Resistance 48415.7 Proximity Effect 48815.8 Superconductors as Nanomaterials 49015.9 Tunneling and Josephson Junctions 49115.9.1 Tunneling 49115.9.2 Weak Links 49115.9.3 Josephson Effect 49315.9.4 Josephson Junctions 49415.9.5 Ultrasmall Josephson Junctions 49415.10 Superconducting Quantum Interference Device (Squid) 49515.11 Buckministerfullerenes 49615.11.1 The Structure of C60 and Its Crystal 49615.11.2 Alkali-Doped C60 49615.11.3 Superconductivity in C60 497Problems 498References 499Appendix A Formulas for Dimensionality 501A.1 Introduction 501A.2 Delocalization 501A.3 Square and Parabolic Wells 502A.4 Partial Confinement 503Appendix B Tabulations of Semiconducting Material Properties 507Appendix C Face-Centered Cubic and Hexagonal Close-Packed Nanoparticles 515C.1 Introduction 515C.2 Face-Centered Cubic Nanoparticles 515C.3 Hexagonal Close-Packed Nanoparticles 519Index 521

"This book would be an excellent choice for a one- or two-semester course in a materials science, chemistry, or physics course. It would also be of interest to any of our readers interested in learning about nanotechnology. It is written to provide the reader with a sound foundation for understanding the key fundamentals of nanotechnology. This book will be popular." (IEEE Electrical Insulation Magazine, January/February 2009)