Pump-probe optical spectroscopy

Pulse radiolysis stroboscopic detection

The short pulse of ionization radiation initiates radical reactions. In this case, 5 ps electron pulse ionizes water and form several radicals. One can easily follow after solvated electron concentration in a solution by following its absorption spectrum change in time using the sequence of short laser probe pulses, e.g., white-light (supercontinuum), at different time-delays between probes and initial electron pulse.  

C₃₇ – value determination

C37 - is the value that represents the concentration of a solute when 37% of the initial concentration for a given molecule, that reacts with a solute. Often in radiation chemistry, this concept is applied to the solvated electron when necessary to study the reactivity of presolvated electrons with a solute with a limited time-resolution. This happens quite often due to short solvation times of excess electron, e.g., in water, solvation occurs within 1ps time-scale.
Below, the scheme explains how the C37 can be determined based on an example of a presolvated electron interacting with a solute.