This monograph covers a broad spectrum of topics in the very broad field of gas phase molecular collision dynamics. The Introduction previews each of the four fol­ lowing topics and attempts to sew them together with a common thread. In addition, a brief review of quantum reactive scattering is given there along with some gen­ eral remarks which highlight the difficulties in doing quantum reactive scatter­ ing calculations. The chapters are all written by theoreticians who are, of course, experts in the subjects they have written about. Three chapters, the ones by Secrest, Schatz, and the one by Schinke and Bowman deal with non-reactive atom-molecule scattering. Col­ lectively, they describe nearly the full breadth of scattering methods in use to­ day, from fully quantum mechanical to semiclassical and quasiclassical. The chapter by Baer is the only one dealing with quantum reactive scattering with the additional complexity of the coupling of two potential energy surfaces. The one simplifying feature of the treatment is that the reaction is constrained to be collinear. Overall, this monograph is mainly a review of the recent advances in the field of molecular collision dynamics, with, however, a considerable amount of new material. It is hoped that workers and students in the field will find reading the mono­ graph both enlightening and enjoyable.

1. Introduction.- References.- 2. Inelastic Vibrational and Rotational Quantum Collisions.- 2.1 General Computational Techniques.- 2.2 A Higher-Order 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.- 3.3 Trajectory Studies of Polyatomic Molecule Collisions.- 3.4 Collisional Excitation in He + SO2.- 3.5 Conclusion.- References.- 4. Rotational Rainbows in Atom-Diatom Scattering.- 4.1 Background.- 4.2 Review of Rainbows in Isotropic Potential Scattering.- 4.3 Classical Limit of the IOS Approximation.- 4.4 Numerical Examples.- 4.5 Recent Experiments and Comparison with Theory.- 4.6 Approximate Analytical Expressions for X(?,?),J(?,?) and the Rainbow Curve jR(?).- 4.7 Conclusion and Prognosis.- References.- 5. Quantum Mechanical Treatment of Electronic Transitions in Atom-Molecule Collisions.- 5.1 The General Approach.- 5.2 Numerical Examples.- 5.3 Electronic Nonadiabatic Processes Among Potential Curves.- 5.4 Electronic Nonadiabatic Processes in Strong Laser Fields.- 5.5 Summary and Conclusions.- References.