Topics in Current Physics

1. Introduction.- References.- 2. Inelastic Vibrational and Rotational Quantum Collisions.- 2.1 General Computational Techniques.- 2.1.1 The Scattering Equations.- 2.1.2 Boundary Conditions.- 2.1.3 Asymptotic Approximations.- 2.2 A Higher-Order Coupled States Approximation.- 2.2.1 The Phase in the Body Fixed Coordinate System.- 2.2.2 Correcting the Coupled States Approximation.- References.- 3. Quasiclassical Trajectory Studies of State to State Collisional Energy Transfer in Polyatomic Molecules.- 3.1 Background.- 3.2 Semiclassical Vibration-Rotation Motions of Polyatomic Molecules.- 3.2.1 Classical Molecular Hamiltonian.- 3.2.2 Rotational-Vibrational Partitioning.- 3.2.3 Vibrational Semiclassical Eigenstates: Classical Perturbation Theory.- 3.2.4 Rotational Motions and Eigenstates.- 3.3 Trajectory Studies of Polyatomic Molecule Collisions.- 3.3.1 Trajectory Initial Conditions.- 3.3.2 Trajectory Final Conditions.- 3.3.3 Assignment of Final Quantum States.- 3.4 Collisional Excitation in He + SO2.- 3.4.1 Details of Trajectory Calculations.- 3.4.2 Trajectory Results.- 3.5 Conclusion.- References.- 4. Rotational Rainbows in Atom-Diatom Scattering.- 4.1 Background.- 4.1.1 Experiment.- 4.1.2 Theory.- 4.1.3 Outline.- 4.2 Review of Rainbows in Isotropic Potential Scattering.- 4.3 Classical Limit of the IOS Approximation.- 4.3.1 Basic IOS Formulas.- 4.3.2 Classical Limit of (4.14) for j = 0.- 4.3.3 Uniform Approximation.- 4.3.4 Qualitative Behavior of Cross Sections.- 4.3.5 Relationship to Other Work.- 4.4 Numerical Examples.- 4.4.1 Homonuclear Case.- 4.4.2 Heteronuclear Case.- 4.5 Recent Experiments and Comparison with Theory.- 4.5.1 State-Unresolved Experiments.- 4.5.2 State-Resolved Experiments.- 4.6 Approximate Analytical Expressions for X(?,?),J(?,?) and the Rainbow Curve jR(?).- 4.6.1 Hard Shell Scattering.- 4.6.2 High Energy Approximation.- 4.7 Conclusion and Prognosis.- References.- 5. Quantum Mechanical Treatment of Electronic Transitions in Atom-Molecule Collisions.- 5.1 The General Approach.- 5.1.1 The Diabatic Representation.- 5.1.2 The Adiabatic Representation.- 5.1.3 The Adiabatic-Diabatic Transformation.- 5.1.4 The Adiabatic-Diabatic Transformation in Three Dimensions.- 5.2 Numerical Examples.- 5.2.1 Reactive Systems.- (a) The (H2 + H)+ System.- (b) The (Ar + H2)+ System.- (c) The Ba + N2O System.- (d) The F + H2 System.- 5.2.2 Nonreactive Systems.- 5.3 Electronic Nonadiabatic Processes Among Potential Curves.- 5.3.1 Reducing the Surface Crossing Problem to a Curve Crossing Problem.- 5.3.2 The Two-Curve Model.- 5.3.3 A Multi-Curve Crossing Model for Reactions.- (a) The Model.- (b) The Simplified Models.- 5.4 Electronic Nonadiabatic Processes in Strong Laser Fields.- 5.5 Summary and Conclusions.- References.