The theory of the chemical interaction of molecules with surfaces has advanced handsomely in the last few years. This is due in part to the application of the entire arsenal of bulk solid-state theory and molecular quantum chemistry methods. This considerable activity was stimulated by an outpouring of experimental data, particularly of photoemission spectra. In many cases the theoretical techniques are now such that accurate, atomistic pictures of chemisorption phenomena are computed from first principles. This level of capability has been reached only recently, and has not been described anywhere in a comprehensive manner. The purpose of this monograph is to review these recent advances and, at the same time, to indicate a number of important questions which have not been answered. We discuss chemisorption on oxides, semiconductors, and both simple and transition metals. Solid surfaces as well as clusters are considered. While the review should be valuable to workers in the field, care has been taken to make the chapters understandable to the nonspecialist.

Table of Contents:
1. Introduction..- 2. Density Functional Theory of Chemisorption on Simple Metals.- 2.1 Background Information.- 2.1.1 Importance of Self-Consistency.- 2.1.2 Density Functional Theory.- 2.2 Statistical Approach.- 2.2.1 Linear Response Function.- 2.2.2 Chemisorption on Jellium: Hydrogen and the Alkalies.- 2.2.3 Effect of Field Emission Fields on Chemisorption.- 2.2.4 Perturbative Introduction of Single Crystal Lattice Structure for the Substrate: Application to Aluminum Substrate.- 2.2.5 Nonlinear Response for Sodium Chemisorption.- 2.3 Approach Based on the Solution of Effective One-Electron Schrodinger Equation.- 2.3.1 Methods of Solving the Kohn-Sham Equation for Chemi-sorption Systems.- 2.3.2 Single-Atom Chemisorption on Jellium; H, Li, 0, Na, Si and Cl.- 2.3.3 Reintroduction of Single-Crystal Lattice Structure; Si, 0, and H on Al.- 2.3.4 Core Hole and Relaxation Effects; 0, Na, Si and Cl.- 2.4 Concluding Remarks.- References.- 3. Chemisorption on Semiconductor Surfaces.- 3.1 Background Information.- 3.2 Bulk Properties.- 3.3 General Surface Properties.- 3.4 Computational Approaches.- 3.5 Clean Semiconductor Surfaces.- 3.6 H Chemisorption on Si Surfaces.- 3.6.1 H on Si (111) -Simple Phase.- 3.6.2 H on Si (111)-Disordered.- 3.6.3 H on Si (111)-Trihydride Phase.- 3.6.4 H Chemisorbed on 2 x 1 Si (100).- 3.6.5 H Interacting with lxl Si (100).- 3.7 Cl Chemisorption on Si (111) and Ge(lll).- 3.8 Al Chemisorption on Si (111).- 3.9 Al Chemisorption on GaAs(llO).- References.- 4. Chemisorption on d-Band Metals.- 4.1 Moments Method.- 4.2 Muffin-Tin Methods.- 4.3 Parametrized LCA0 Methods.- 4.3.1 Slater-Koster Method for Clean Surfaces.- 4.3.2 Extended Huckel Theory.- 4.3.3 Parametrized LCA0 for Chemisorption.- 4.3.4 Tight Binding.- 4.4 Linear Combination of Muffin-Tin Orbitals (LCMT0) Method.- 4.5 Self-Consistent Methods.- 4.5.1 Gaussian Expansion Method.- 4.5.2 Numerical Basis Set Method.- 4.6 Fully Self-Consistent Methods.- 4.6.1 Pseudopotential Method.- 4.6.2 Self-Consistent Local Orbital Method.- 4.7 Summary.- References.- 5. Cluster Chemisorption..- 5.1 Ideal Choice of Problem for Cluster Simulation.- 5.2 Methods of Obtaining a Solution.- 5.3 Interaction of Cluster and Environment.- 5.4 Examples of Cluster Calculations.- References.- 6. Concepts of Surface States and Chemisorption on d-Band Perovskites.- 6.1 Introductory Remarks.- 6.1.1 General Comments.- 6.1.2 The Perovskites.- 6.2 Cluster Models of Transition Metal Oxides.- 6.3 Bulk and Surface Electronic Properties of the Perovskites.- 6.3.1 Bulk Electronic Properties.- 6.3.2 Surface Electronic Properties.- 6.3.3 Qualitative Features of Chemisorption.- 6.3.4 Effect of Electron-Electron Interactions.- 6.4 Surface Oxygen Vacancy States (SOVS).- 6.5 Photoemission Experiments on SrTi03.- 6.5.1 Surface State Emission.- 6.5.2 Comparisons with Theory.- 6.5.3 Oxygen Adsorption on (100) SrTi03.- 6.6 Summary.- References.- 7. Theoretical Issues in Chemisorption.- 7.1 Local Density Approximations and Generalizations.- 7.1.1 Excitation Spectrum.- 7.2 The Anderson Model Picture.- 7.2.1 Hartree-Fock Calculations for Simple Tight-Binding Model Substrates: Surface Densities of States.- 7.2.2 Improvements of the Anderson Model.- 7.3 Beyond the Hartree-Fock Theory.- 7.3.1 The Valence-Bond Picture.- 7.3.2 Spin Fluctuation Model.- 7.3.3 Interpolative Decoupling Methods.- 7.3.4 Variational Methods.- 7.4 Adatom-Adatom Interactions.- 7.5 Photoemission.- 7.6 Concluding Remarks.- References.