Collision Spectroscopy

1. The Subject.- 2. Metastable Ions.- 3. Types of Collisions.- 4. Collision Cross Sections.- 5. Energy Interconversions.- 6. Energy Resolution and Angular Resolution.- 7. Laboratory and Center-of-Mass Coordinate Systems.- 8. Guideposts to the Contents.- References.- 1 Collisional Excitation of Simple Systems.- 1. Introduction.- 1.1 Types of Collisions.- 1.2. Elements of Collision Theory.- 1.3. Experimental Methods.- 2. Determination of Excitation Cross Sections from Ion Energy- Loss Spectrometry.- 2.1. Apparatus.- 2.2. Analysis of the Energy-Loss Spectrometric Method.- 3. Determination of Excitation Cross Sections from Photon Emission Data.- 3.1. Incident Particle Flux Determination.- 3.2. Target Density Determination.- 3.3. Photon Flux Determination.- 4. The Excitation of Atomic Hydrogen.- 4.1. Modulated Crossed-Beam Technique.- 4.2. Energy-Loss Spectra of Atomic Hydrogen.- 5. Excitation of Helium.- 5.1. Energy-Loss Spectra of Helium.- 5.2. Optical Studies of the Excitation of Helium.- 6. Differential Cross-Section Measurements.- 7. Excitation of Simple Molecules.- 7.1. Excitation of Molecular Hydrogen.- 7.2. Excitation of Molecular Nitrogen.- 7.3. Excitation of Molecular Oxygen.- 7.4. Excitation of Singlet-Triplet Transitions.- 8. Discussion.- References.- 2 Charge Transfer in Atomic Systems.- 1. Introduction.- 2. Theory.- 2.1. Introduction.- 2.2. Semiclassical Cross Sections Differential in Angle and Energy.- 2.3. Transition Probabilities and Energy-Loss Spectra.- 2.4. General Considerations.- 3. Experimental Methods.- 3.1. Introduction.- 3.2. Pressure Measurement.- 3.3. Detectors.- 3.4. Beam Production.- 3.5. Cross-Section Measurements.- 4. Experimental Data and Interpretation.- 4.1. Introduction.- 4.2. Integrated Cross Sections.- 4.3. Energy-Loss Spectra with Doubly Charged Ions.- 4.4. Angular Differential Cross Sections.- 4.5. Cross Sections Differential in Angle and Energy.- 5. Summary.- References.- 3 Inelastic Energy Loss: Newer Experimental Techniques and Molecular Orbital Theory.- 1. Introduction.- 2. The Molecular Orbital Model.- 2.1. Molecular Orbitals for Collision Processes.- 2.2. Transitions between Molecular Orbitals.- 3. Experimental Techniques and Results.- 3.1. Energy-Loss Measurements.- 3.1.1. A Typical Scattered-Particle Apparatus.- 3.1.2. Time-of-Flight Measurements.- 3.1.3. The Use of Molecular Targets.- 3.1.4. Inner-Shell Excitations.- 3.2. Ion-Photon and Ion-Electron Coincidence Measurements.- 3.2.1 Introduction.- 3.2.2. Experimental Principles.- 3.2.3. Charge-Exchange Measurements Using Coincidence Techniques.- 3.2.4. Stueckelberg Oscillations.- 3.2.5. Rosenthal Oscillations and Long-Range Couplings.- 3.2.6. Polarization and Angular Distribution Measurements in Coincidence.- 3.2.7. Ion-Molecule Coincidence Measurements.- 4. Summary and Conclusion.- References.- 4 Double Electron Transfer and Related Reactions.- 1. Introduction.- 2. Cross Sections.- 3. Experimental Techniques of Double-Charge-Transfer Spectroscopy.- 3.1. The Instrument.- 3.2. The Energy-Loss Scale.- 3.3. An Apparatus with Higher Energy Resolution.- 3.4. Target Pressure Dependences of the Negative Ion Intensities.- 4. (H+, M) Spectra and the Study of the States of the Target Species.- 4.1. The Spin Conservation Rule.- 4.2. The Applicability of the Franck-Condon Principle.- 4.3. Selection Rules for the Symmetry of the Molecular States.- 4.4. Observation of Double-Charge-Transfer Processes at Different Scattering Angles.- 4.5. Determination of the Double-Ionization Potentials of Some Molecules.- 4.6. Observation of Radiative Transitions without Detection of thePhoton.- 5. (A+, Ar) Spectra: An Insight into Future Possible Developments.- 5.1. Determination of the State Composition of the A+Bearn.- 5.2. Determination of the Geometric Structure of a Polyatomic A+orA-Ion.- 5.3. The Electron Affinity of the Projectile Species A.- 5.4. Dissociative Double-Charge-Transfer Spectra.- Appendix: Energy Loss of the Projectile in an Inelastic Collision.- References.- 5 Ionic Collisions as the Basis for New Types of Mass Spectra.- 1. Introduction.- 2. 2E Mass Spectra.- 3. -E Mass Spectra.- 4. E/2 Mass Spectra.- 5. +E Mass Spectra.- 6. Other Types of Spectra.- References.- 6 Collision-Induced Dissociation of Diatomic Ions.- 1. Introduction.- 2. Dynamics of Dissociation.- 2.1. The Two-Step Model.- 2.2. Electronic Excitation.- 2.3. Vibrational/Rotational Dissociation.- 2.4. Predissociation.- 3. Experimental Techniques.- 3.1. The Aston Band Method.- 3.2. Initial-State Preparation.- 3.3. Final-State Analysis.- 3.4. The Apparatus Function.- 4. Direct Dissociation in Heavy-Particle Collisions.- 4.1. The Dissociation of H+2.- 4.2. The Dissociation of HeH+.- 4.3. Discussion.- 5. Translational Spectroscopy.- 5.1. Collisional Dissociation of 4-10 keV N+2 Ions.- 5.2. Collisional and Unimolecular Dissociation of 10-keV HeH+ Ions.- 5.3. Photodissociation of H+2.- 6. Concluding Remarks.- References.- 7 Collision-Induced Dissociation of Polyatomic Ions.- 1. Introduction.- 1.1. Scope of Chapter.- 1.2. Comparison with Metastable Ions.- 1.3. Development of CID Studies.- 2. The Reaction.- 2.1. The Basic Phenomenon and Its Experimental Characterization.- 2.2. Mechanism.- 2.3. Cross Section.- 2.4. Effects of Experimental Variables.- 3. Experimental Procedures.- 3.1. Instrumentation and Scanning Methods.- 3.2. Energy Resolution and Kinetic Energy Measurement.- 3.3. Other Considerations.- 4. Applications.- 4.1. Ion Structure Determination.- 4.2. Thermochemical Determinations.- 4.3. Fragmentation Mechanisms.- 4.4. Molecular Structure Determination.- 4.5. Analysis of Mixtures and Isotope Incorporation.- 4.6. Product Characterization in Ion-Molecule Reactions and Other Applications.- 5. Related Reactions.- 5.1. Negative Ions.- 5.2. Dissociative Charge Transfer.- 5.3. Related Ion-Surf ace Reactions.- 5.4. Related Photodissociations.- 5.5. CID Studied by Ion-Cyclotron Resonance Spectrometry.- 5.6. CID of Neutral Molecules.- 6. Prospects.- References.