Electron-Molecule Collisions

1. Introduction to Electron-Molecule Collisions.- 1. Introduction.- 2. Cross Sections.- 2.1. Concept of Cross Sections.- 2.2. Experimental Arrangements.- 2.3. Theoretical Studies of Electron-Molecule Collisions.- 2.4. Examples of the Electron-Molecule Collision Cross Sections.- 3. Electron-Molecule Interactions.- 3.1. Long-Range Interactions.- 3.2. Short-Range Interactions.- 4. Resonance Effect.- 5. Calculation of the Total Cross Section as a Potential Scattering Problem.- 5.1. Summary of the Theory for Scattering from a Central Field.- 5.2. Independent-Atom Model.- 5.3. One-Center Expansion of Nonspherical Potential.- 5.4. Separable Potentials.- 5.5. Polyatomic Molecules.- 6. Theoretical Formulation of Inelastic Scattering Processes.- 6.1. Outline of the General Theory.- 6.2. Born Approximation.- 6.3. Some Consequences of the Born Approximation. I: Elastic Collisions and Rotational Transitions.- 6.4. Some Consequences of the Born Approximation. II: Vibrational Transitions.- 6.5. Some Consequences of the Born Approximation. III: Electronic Transitions.- 6.6. Electron Exchange.- 6.7. Distorted-Wave Approximations.- 6.8. Adiabatic Approximations.- References and Notes.- 2. Rotational Excitation of Molecules by Slow Electrons.- 1. Introduction.- 2. Classical Sudden Collisions and Angular-Momentum Transfer.- 2.1. Linear Rotators.- 2.2. Nonlinear Rotators.- 3. Quantum-Mechanical Sudden Collisions and Angular-Momentum Transfer.- 3.1. Elementary Theory of Angular Momentum.- 3.2. Sudden Approximation.- 3.3. General Relations for the Cross Sections.- 4. Division of the Configuration Space.- 4.1. Dynamics in Different Regions.- 4.2. Frame Transformation.- 4.3. R-Matrix Theory.- 5. Physics in the Potential Scattering Region.- 5.1. General Trend of the Cross Sections.- 5.2. Single-Center Expansion of the Interaction Potential.- 5.3. Charge-Dipole Interaction.- 5.4. Charge-Quadrupole Interaction.- 5.5. Interaction of Shorter Range.- 6. Physics in the Compound-System Region.- 6.1. Multicenter Electrostatic Field.- 6.2. Indistinguishability of All Electrons.- 6.3. Representation in Terms of Adiabatic Angular Basis Set.- Appendix: Summary of Formulas.- References and Notes.- 3. Vibrational Excitation of Molecules by Slow Electrons.- 1. Introduction.- 2. Virtual States and Resonances.- 2.1. Introduction.- 2.2. Potential Well Scattering with l = 0.- 2.3. Potential Well Scattering with l > 0.- 2.4. Singularities in Potential-Well Scattering.- 2.5. Time Delay.- 2.6. General Resonances.- 3. Vibrational Excitation. I: Wave-Function Enhancement without Trapping.- 4. Vibrational Excitation. II: Electron Scattering at a Shape Resonance; Impulse Limit.- 5. Vibrational Excitation. III: Long-Lived Resonances and Nuclear Relaxation.- 5.1. The Nuclear Wave Equation.- 5.2. Solutions of the Nuclear Wave Equation-Qualitative Features.- 5.3. The Complex Potential Surface.- 5.4. Semiempirical Calculations.- 5.5. Ab Initio Calculations in the Born-Oppenheimer Approximation.- 5.6. Other Calculations.- 6. Current Developments.- 6.1. Electronic Excitation.- 6.2. High Excitation Energies.- 6.3. More Complicated Targets.- 6.4. Rotational Effects.- Appendix A: Resonance Scattering of Electrons by a Target with Fixed Nuclei.- Appendix B: Resonance Scattering of an Electron by a Molecule with Relaxing Nuclei.- Appendix C: The Impulse Approximation.- Appendix D: Wave Packets.- References and Notes.- 4. Dissociation of Molecules by Slow Electrons.- 1. Introduction.- 2. Dissociation of Molecules into Ground Electronic State Fragments.- 3. Dissociation into Excited Fragments.- 3.1. Dissociation of Molecules into Fragments Which Emit Radiation.- 3.2. Metastable Fragments.- 3.3. High Rydberg Fragments.- 4. Dissociative Ionization.- 5. Dissociative Attachment.- 5.1. H2 and D2.- 5.2. N2 and NO.- 5.3. O2.- 5.4. F2, C12, Br2, and I2.- 5.5. Hydrogen Halides.- 5.6. Triatomic Molecules.- 5.7. Halogenated Methanes.- 6. Dissociative Attachment to Ultracold Molecules and Molecular Clusters.- 7. Dissociative Recombination.- 7.1. Plasmas.- 7.2. Colliding Beams.- 7.3. Ion Trap.- 7.4. Theoretical Calculations and Experimental Results.- References and Notes.- 5. Molecular Spectroscopy By Electron Scattering.- 1. Introduction.- 2. Resonance Spectroscopy of Molecules.- 2.1. The Grandparent Model and Feshbach Resonances.- 2.2. Coupling Mechanisms of Feshbach Resonances. I: Electronic Coupling.- 2.3. Coupling Mechanisms of Feshbach Resonances. II: Dynamic Coupling.- 2.4. Potential Curves of Feshbach Resonances in H2.- 2.5. Resonance Symmetry and Differential Cross Sections.- 2.6. Resonance Symmetry and Rotational Structure.- 2.7. Core-Excited Shape Resonances. I: Valence States.- 2.8. Core-Excited Shape Resonances. II: Rydberg States.- 3. Electron Energy-Loss Spectroscopy.- 3.1. Molecular Outer-Shell Spectroscopy at High Incident Electron Energies.- 3.2. Inner-Shell Excitation.- 3.3. Electron Scattering Spectroscopy at Intermediate Energies.- 3.4. Electron Scattering Spectroscopy at Near-Threshold Energies.- References.- 6. Experimental Techniques for Cross-Section Measurements.- 1. Introduction.- 2. Definition of Cross Sections.- 3. Measurement of Total, Integral, and Momentum-Transfer Cross Sections.- 3.1. Total Cross Sections.- 3.2. Integral Cross Sections.- 3.3. Momentum-Transfer Cross Sections.- 4. Measurement of Differential Cross Sections.- 4.1. Instrumentation.- 4.2. Relation between Cross Section and Scattering Signal Intensity in Beam-Beam Experiments.- 4.3. Normalization Procedures.- 4.4. Experimental Techniques and Procedures.- 4.5. Discussion of Experimental Uncertainties.- 5. Electron Collision Measurements at High Energies; Generation of Optical Data.- 6. Electron Scattering in Electromagnetic Fields.- 7. Closing Remarks.- References.- 7. Computational Methods for Low-Energy Electron-Molecule Collisions.- 1. Introduction.- 2. Derivation of the Radial Equations.- 2.1. Electronic and Rotational Degrees of Freedom.- 2.2. The Vibrational Motion.- 3. Numerical Solution of the Fixed-Nuclei Equations.- 3.1. Single-Center Expansion Methods.- 3.2. Expansion in Prolate Spheroidal Coordinates.- 3.3. Separable Exchange Potentials.- 3.4. Model Exchange Potentials.- 3.5. Polarization Potentials.- 3.6. Continuum Multiple-Scattering Method.- 3.7. L2 Methods.- 3.8. R-Matrix Method.- 3.9. T-Matrix Method.- 4. Vibrational Excitation and Dissociative Attachment.- 4.1. Adiabatic Nuclei Approximation.- 4.2. Hybrid Theory.- 4.3. Resonance Theory.- 4.4. R-Matrix Method.- 5. Electronic Excitation.- 5.1. Excitation of H+2.- 5.2. Excitation of H2.- 5.3. Excitation of N2.- 6. Conclusions.- References.