This Physical Chemistry textbook addressed the study of macroscopic, and particulate phenomena in chemical systems in terms of the principles, practices, and concepts of physics such as motion, energy, force, time, thermodynamics, quantum chemistry, statistical mechanics, analytical dynamics and chemical equilibria. In contrast to chemical physics, physical chemistry is predominantly (but not always) a macroscopic or supra-molecular science, as the majority of the principles on which it was founded relate to the bulk rather than the molecular/atomic structure alone. Front Matter 1: The Dawn of the Quantum Theory 2: The Classical Wave Equation 3: The Schrödinger Equation and a Particle in a Box 4: Postulates and Principles of Quantum Mechanics 5: The Harmonic Oscillator and the Rigid Rotor 6: The Hydrogen Atom 7: Approximation Methods 8: Multielectron Atoms 9: Chemical Bonding in Diatomic Molecules 10: Bonding in Polyatomic Molecules 11: Computational Quantum Chemistry 12: Group Theory - The Exploitation of Symmetry 13: Molecular Spectroscopy 14: Nuclear Magnetic Resonance Spectroscopy 15: Lasers, Laser Spectroscopy, and Photochemistry 16: The Properties of Gases 17: Boltzmann Factor and Partition Functions 18: Partition Functions and Ideal Gases 19: The First Law of Thermodynamics 20: Entropy and The Second Law of Thermodynamics 21: Entropy and the Third Law of Thermodynamics 22: Helmholtz and Gibbs Energies 23: Phase Equilibria 24: Solutions I - Volatile Solutes 25: Solutions II - Nonvolatile Solutes 26: Chemical Equilibrium 27: The Kinetic Theory of Gases 28: Chemical Kinetics I - Rate Laws 29: Chemical Kinetics II- Reaction Mechanisms 30: Gas-Phase Reaction Dynamics 31: Solids and Surface Chemistry 32: Math Chapters 33: Appendices Back Matter Thumbnail: Space-filling model of the LUMO of pyridine. Structure calculated and image produced using HF/6-31G*. (Public Domain; Ben Mills via Wikipedia )