Chemistry
How Electron Paramagnetic Resonance Detects Radicals in Chemical Reactions
Quick fact
EPR is so sensitive to unpaired electrons that it can detect radical concentrations as low as 10^-10 molar, and it can even follow the formation and decay of radicals in a reaction in real time.
Why this is interesting
You’ve probably heard of MRI and NMR, but did you know that a related technique can actually 'see' the unpaired electrons that drive many chemical reactions? How does it work?