48:35 6. Electron Shell Model, Quantum Numbers, and PES (Intro to Solid-State Chemistry) MIT OpenCourseWare
49:23 8. Ionization Energy and Potential Energy Surface (PES) (Intro to Solid-State Chemistry) MIT OpenCourseWare
49:36 Additional Lecture 2. The Chemistry of Batteries (Intro to Solid-State Chemistry 2019) MIT OpenCourseWare