Physical Chemistry III covers the introduction of quantum chemistry and molecular spectroscopy. In quantum chemistry, students are exposed to the basic principles that govern the structure and properties of individual atoms and molecules. The experimental results that overthrew the concepts of classical mechanics will also be discussed. In molecular spectroscopy, students will learn the fundamental concepts of rotational and vibrational spectroscopy, the electronic spectra of diatomic and polyatomic molecules, and the fundamental concepts of magnetic resonance spectroscopy.