1. Ground-State Potential Surfaces and Thermochemistry.- 1. Introduction.- 2. Macroscopic Properties from Molecular Calculations.- 3. Semiempirical Molecular Orbital Theory for Closed Shells.- 4. Exploring Potential Energy Surfaces.- 5. Selected Results and Comparisons.- 6. Conclusions and an Opinion.- References.- 2. Electronic Excited States of Organic Molecules.- 1. Introduction.- 2. The Hamiltonian Operator.- 3. The Zeroth-Order Approximation.- 4. The Electronic Wave Function.- 5. The Interaction of Matter and Electromagnetic Fields.- 6. Spin-Orbit and Spin-Spin Coupling.- 7. Vibrationally Induced Transitions.- 8. Application of ZDO Methods.- 9. Conclusions.- References.- 3. Photochemistry Josef Michl.- 1. Introduction.- 2. Photochemical Processes.- 3. Semiempirical Methods.- 4. Examples of Application.- 5. Summary and Outlook.- References.- 4. Approximate Methods for the Electronic Structures of Inorganic Complexes.- 1. Inorganic Complexes Contrasted to Organic Molecules.- 2. TheOrbitals.- 3. The Ligand Field and the Crystal Field Methods.- 4. Koopmans’ Theorem.- 5. Spin-Orbit Coupling.- 6. NonempiricalCNDO and INDO Methods.- 7. Semiempirical CNDO and INDO Methods.- 8. The Excited States.- 9. The Crystal Field Theory.- 10. Extended Hückel Theory. Angular Overlap Model.- 11. An Example, Ni(CN)4~. Conclusions.- References.- 5. Approximate Molecular Orbital Theory of Nuclear and Electron Magnetic Resonance Parameters.- 1. Introduction.- 2. Magnetic Resonance Parameters.- 3. Molecular Quantum Mechanics.- 4. NMR Shielding Constants and Chemical Shifts.- 5. NMR Nuclear Spin Coupling Constants.- 6. ESRg-Tensors.- 7. ESR Electron-Nuclear Hyperfine Tensors.- 6. The Molecular Cluster Approach to Some Solid-State Problems.- 1. Introduction.- 2. Solid-State TheoryApproaches to Surface Problems.- 3. Molecular Cluster Approach to Surface Problems.- 4. Summary.- References.- 7. Electron Scattering Donald G. Truhlar.- 1. Introduction.- 2. Explicit Inclusion of Electronic Excitations.- 3. Neglect of Electronic Excitation Except for Final State.- 4. Inclusion of Effect of Omitted Electronic States by Approximate Polarization Potentials.- References.- Author Index.- Molecule Index.