Interested in learning more about photochemistry? Here are Spencer's lecture notes from his graduate course, CHEM 6420: Introduction to Photochemistry.
Lecture 1 Molecular Photochemistry of Organic Compounds  Lecture 2 Electronic Vibrational and Spin Configurations of Electronically Excited States  Lecture 3 Transitions between States Photophysical Processes 
 Lecture 4 Radiative Transitions between Electronic States  Lecture 5 Energy and Electron Transfer  Lecture 6 The Photochemistry of Rubpy32
 Lecture 7 Instrumentation and Experimental Techniques  Lecture 8 Photoredox Catalysis