Production of hydrated electrons from photoionization of dissolved organic matter in natural waters.

Under UV irradiation, an important primary photochemical reaction of colored dissolved organic matter (CDOM) is electron ejection to produce hydrated electrons (e-aq). The efficiency of this process has been studied in both fresh water and seawater samples with both steady-state scavenger (S-SS) and time-resolved laser flash photolysis (LFP) methods. However, the apparent quantum yields (AQYs) of e-aq for the same samples using the two methods differ by as much as a factor of 100, necessitating a closer re-examination of how the process is measured.