Postcollision interaction in the liquid phase: The role of electron scattering

We report a detailed study of postcollision interaction (PCI) in a liquid medium. We investigate PCI for the Auger KLL electrons of solvated ${\mathrm{Cl}}^{\ensuremath{-}}, {\mathrm{K}}^{+}$, and ${\mathrm{Ca}}^{2+}$. All three isoelectronic ions exhibit a very similar PCI behavior, which is little affected by changing the solvent from water to methanol or ethanol. The two main factors modifying the PCI interaction in condensed media are the screening of Coulombic interactions and scattering of the electrons. The experimental results are compared with the predictions of a previously reported semiclassical PCI theory modified to account for screening and scattering. We show that a better agreement with experiment can be obtained by instead modeling scattering using electron transport Monte Carlo simulations. We suggest that, in turn, PCI experimental data could be used as another experimental constraint to refine the currently insufficiently well-known scattering parameters of low-energy electrons in water, which are crucial in many fields.