Abstract :
Based on the hypothesis that a mobile (quasi-free) precursor of the localized “infrared” electron exists in water, a new mechanism of photoionization of liquid water is proposed to describe the data on picosecond and femtosecond laser photolysis. According to this mechanism, the fast recombination of the mobile electron with its parent ion governs both the quantum yield and absorption kinetics of the localized electrons. The proposed mechanism is consistent with experiment at the mobile electron diffusion length Ld = (6D0t0)12 = 1.6–3.0 nm where D0 is the diffusion coefficient of the mobile electron and t0 is its localization time. A new physical interpretation of the time dependent electron absorption dynamics on the time scale ≈10−13 s is given.
