The statistical theory of unimolecular reactions is now universally known as RRKM theory. This textbook covers the basics necessary for the understanding of RRKM theory in its original and variational, phase-space and angular momentum-conserved incarnations. After a review of the Kassel quantum model and the theory of Slater, the specific-energy RRKM rate constant k(E) is derived. The argument is then extended to the angular momentum-dependent rate constant k(E,J), to non-classical effects (tunneling and non-adiabatic transition), and the general problem of angular momentum conservation. A long chapter is devoted to the counting of quantum states. The chapter on thermal systems discusses both analytical and numerical solutions and is later extended to include the variational approach and discussion of exit channel effects. Containing many problem sets and solutions, the book is targeted at graduate and advanced undergraduate students studying chemical dynamics, chemical kinetics and theoretical chemistry.

• Highly illustrated • Contains numerous problem sets and worked solutions • Numerous appendices containing more detail on much of the mathematics contained in the main text

### Contents

Introduction; 1. The RRK model; 2. Outline of the theory of Slater; 3. The RRKM rate constant; 4. Calculation of energy level densities; 5. Unimolecular reactions in a thermal system; 6. Non-classical effects near barrier maximum; 7. A variational transition state theory; 8. Unimolecular decomposition under a central potential; 9. Non-central potential and exit channel effects; Appendices; Answers to selected problems.

### Review

'The striking element of this book is its elegant, yet simple, presentation of the unimolecular reactions … Students will appreciate the readability and clarity of the presentation of this book. This will surely become the modern day "classic".' ChemPhysChem