Treatise on Solid State Chemistry Volume 6A Surfaces I

The last quarter-century has been marked by the extremely rapid growth of the solid-state sciences. They include what is now the largest subfield of physics, and the materials engineering sciences have likewise flourished. And, playing an active role throughout this vast area of science and engineer­ ing have been very large numbers of chemists. Yet, even though the role of chemistry in the solid-state sciences has been a vital one and the solid-state sciences have, in turn, made enormous contributions to chemical thought, solid-state chemistry has not been recognized by the general body of chemists as a major subfield of chemistry. Solid-state chemistry is not even well defined as to content. Some, for example, would have it include only the quantum chemistry of solids and would reject thermodynamics and phase equilibria; this is nonsense. Solid-state chemistry has many facets, and one of the purposes of this Treatise is to help define the field. Perhaps the most general characteristic of solid-state chemistry, and one which helps differentiate it from solid-state physics, is its focus on the chemical composition and atomic configuration of real solids and on the relationship of composition and structure to the chemical and physical properties of the solid. Real solids are usually extremely complex and exhibit almost infinite variety in their compositional and structural features.

of Volume 6A.- 1 The Structure and Thermodynamics of Clean Surfaces—Principles.- 1. Introduction.- 2. Thermodynamics of Surfaces.- 2.1. Estimation of Specific Surface Free Energies.- 2.2. The Effect of Surface Tension on Growth and Surface Reactions.- 2.3. Surface Tension of Multicomponent Systems.- 2.4. The Surface Composition of an Ideal Binary Solution.- 2.5. Thermodynamic Properties of Curved Surfaces.- 3. The Structure of Surfaces.- 4. The Atomic Structure of Clean Surfaces.- 4.1. Nomenclature.- 4.2. Unreconstructed Surfaces That Exhibit Contraction (Expansion) Perpendicular to the Surface Plane or Changes in Chemical Composition.- 4.3. Surface Reconstruction.- 4.4. Stepped High-Miller-Index Surfaces.- 4.5. Detection of Surface Disorder on an Atomic Scale.- 5. The Electronic Structure of Surfaces.- 5.1. The Theory of Electron Surface States.- 5.2. Changes of Work Function.- 5.3. The Studies of Electronic Structure at Surfaces by Emission and Recombination Involving Inner Shell Electrons.- Acknowledgment.- References.- 2 Surface Structure—Experimental Methods.- 1. Introduction.- 1.1. Scope and Organization.- 1.2. Importance of Surface Purity and Surface Order.- 1.3. Experimental Methods.- 2. Chemical Structure.- 2.1. Core-Level Spectroscopies.- 2.2. Ion Scattering Spectroscopy.- 2.3. Secondary Ion Emission and Desorption Methods.- 3. Geometric Structure.- 3.1. Field Ion Microscopy.- 3.2. Reflection Electron Diffraction.- 3.3. Ion and Atom Scattering.- 3.4. High-Resolution Electron Spectroscopy.- 4. Surface Electronic Structure.- 4.1. Characterization of Electronic Structure.- 4.2. Kinds of Experimental Methods.- 4.3. Electron Spectroscopies for Filled States.- 4.4. Electron Spectroscopies for Unfilled States.- 4.5. Basic Characteristics of Surface Electron Spectroscopies.- 4.6. Optical Methods of Studying Surface Electronic Structures.- 4.7. Methods Based on the Semiconductor Space-Charge Layer.- 4.8. Inelastic LEED and Surface Plasmon Dispersion.- Acknowledgments.- References.- 3 Evaporation from Solids.- 1. Introduction.- 2. Principles.- 2.1. Introduction to Kinetic Principles.- 2.2. Vaporization, Condensation, and Thermal Accommodation Coefficients.- 2.3. Introduction to Thermodynamic Principles.- 2.4. Free Evaporation.- 2.5. Systems with More than One Vapor Species.- 3. Experimental Methods.- 3.1. Measurements of Vaporization Rates Far from Equilibrium.- 3.2. Measurements of Vaporization Rates Near Equilibrium.- 3.3. Measurements of Vaporization Coefficients.- 3.4. Supplemental Experiments.- 4. Evaporation Mechanisms of Single Crystals.- 4.1. The Terrace-Ledge-Kink Model.- 4.2. Elements and Isotropic Molecular Solids.- 4.3. Nondissociating Ionic Solids.- 4.4. Dissociating Solids.- 4.5. Associating Vapors.- 5. Sources of Information on Evaporation Rates.- 5.1. Compilations of Vaporization Coefficients for Solids.- 5.2. Sources of Vapor Pressure Data for Solids.- Acknowledgments.- References.- 4 Molecular Beam Deposition of Solids on Surfaces: Ultrathin Films.- 1. Introduction.- 2. Kinetic Impediments for Condensation.- 2.1. Atom—Surface Interaction.- 2.2. Molecule—Surface Interaction.- 3. Nucleation of Solids and Liquids on Surfaces: Theory.- 3.1. Adsorption and Nucleation: Classification of Interfacial Interactions into Four Types.- 3.2. Type I Deposition: Weak Interaction with the Substrate.- 3.3. Type II Deposition: Medium Strong Interaction with the Substrate and Small Lattice Mismatch.- 3.4. Type III Deposition: Strong Interaction, Large Misfit; and Type IV, Reactive Deposition.- 3.5. Computer Simulation of Vapor Deposition.- 4. Experimental Techniques.- 4.1. Molecular Beam Methods.- 4.2. In Situ Transmission Electron Microscopy.- 4.3. Scanning High-Energy Electron Diffraction (SHEED).- 4.4. Multiple Ion Reflection.- 4.5. Field Ion Microscopy (FIM) and Field Emission Microscopy (FEM).- 5. Deposition of Semiconductors.- 5.1. Silicon.- 5.2. Germanium.- 5.3. Gallium Arsenide and Gallium Phosphide.- 5.4. II–VI Compound Semiconductors.- 6. Deposition of Metals.- 6.1. Deposition onto Ionic Substrates and Layered Compounds.- 6.2. Metals on Nonrefractory Metals.- 6.3. Refractory Metal Substrates.- 6.4. Metals on Semiconductors.- 7. Deposition of Thin Films of Noble Gases and Saturated Molecules.- 7.1. Structure of Adsorbed Layers.- 7.2. Kinetics of Nucleation and Growth.- 8. Summary.- List of Symbols.- Acknowledgments.- References.- 5 Adsorption of Gases on Solids.- 1. Introduction.- 1.1. Objectives and Approach.- 1.2. Nature and Development of the Subject.- 1.3. Microscopic Adsorption Properties.- 2. Phenomenological Models and Atomistic Concepts.- 2.1. Nature of Adsorbed Layers.- 2.2. Atomic Composition of Surface Layers.- 2.3. Surface Coverage Measurement.- 2.4. Energetics and Kinetics of Adsorption.- 2.5. Change in Work Function.- 2.6. Atomic Geometry of Surface Layers.- 2.7. Collective Interactions in Adsorption.- 2.8. Vibrational Properties of Adsorbed Layers.- 3. Electronic Properties of Adsorbed Layers.- 3.1. Theoretical Approaches to Chemisorption.- 3.2. Experimental Approaches to Chemisorption.- 4. Some Prototype Adsorption Systems.- 4.1. Adsorption of Diatomic Gases on Tungsten.- 4.2. Adsorption of Oxygen, Sulfur, Selenium, and Tellurium on Nickel.- 5. Summary and Conclusions.- 5.1. Status of Present Work.- 5.2. Directions for Future Study.- Acknowledgments.- References.