This textbook for graduate students and advanced undergraduates in physics and physical chemistry covers the major areas of statistical mechanics and concludes with a demonstration of applications of statistical mechanics at the level of current research. Intended for a one-semester course, the text includes several "asides" on topics that are usually omitted from introductory courses, as well as numerous problems at the ends of chapters.

I Fundamentals: Separable Classical Systems.- Lecture 1. Introduction.- Lecture 2. Averaging and Statistics.- Lecture 3. Ensembles: Fundamental Principles of Statistical Mechanics.- Lecture 4. The One-Atom Ideal Gas.- Aside A. The Two-Atom Ideal Gas.- Lecture 5. N-Atom Ideal Gas.- Lecture 6. Pressure of an Ideal Gas.- Aside B. How Do Thermometers Work-The Polythermal Ensemble.- Lecture 7. Formal Manipulations of the Partition Function.- Aside C. Gibbs's Derivation of.- Lecture 8. Entropy.- Lecture 9. Open Systems; Grand Canonical Ensemble.- II Separable Quantum Systems.- Lecture 10. The Diatomic Gas and Other Separable Quantum Systems.- Lecture 11. Crystalline Solids.- Aside D. Quantum Mechanics.- Lecture 12. Formal Quantum Statistical Mechanics.- Lecture 13. Quantum Statistics.- Aside E. Kirkwood-Wigner Theorem.- Lecture 14. Chemical Equilibria.- III Interacting Particles and Cluster Expansions.- Lecture 15. Interacting Particles.- Lecture 16. Cluster Expansions.- Lecture 17. ? via the Grand Canonical Ensemble.- Lecture 18. Evaluating Cluster Integrals.- Lecture 19. Distribution Functions.- Lecture 20. More Distribution Functions.- Lecture 21. Electrolyte Solutions, Plasmas, and Screening.- IV Correlation Functions and Dynamics.- Lecture 22. Correlation Functions.- Lecture 23. Stability of the Canonical Ensemble.- Aside F. The Central Limit Theorem.- Lecture 24. The Langevin Equation.- Lecture 25. The Langevin Model and Diffusion.- Lecture 26. Projection Operators and the Mori-Zwanzig Formalism.- Lecture 27. Linear Response Theory.- V A Research Problem.- Aside G. Scattering of Light, Neutrons, X-Rays, and Other Radiation.- Lecture 28. Diffusion of Interacting Particles.- Lecture 29. Interacting Particle Effects.- Lecture 30. Hidden Correlations.