Photoionization and Photochemiluminescence of Luminol in Aqueous Solution

UV photolysis of luminol (5-amino-2,3-dihydrophthalazine-1,4-dione) in aqueous solution via one-photon photoionization gives the luminol radical and an hydrated electron, which reacts with the dissolved oxygen to form the superoxide radical; recombination of the luminol radical with superoxide leads to chemiluminescence