Molecular dynamics simulations of the temperature and density dependence of the absorption spectra of hydrated electron and solvated silver atom in water

We report mixed quantum-classical molecular dynamics simulations of the optical absorption spectrum of the solvated silver atom and electron in liquid water. The simple one electron model is shown to be able to reproduce the strong temperature dependence of the absorption spectra of hydrated electron as well as the much weaker dependence for the silver atom. A qualitative explanation is provided for this experimental fact. When extending these simulations to very low densities corresponding to supercritical conditions the results display a progressive 'desolvation' of the hydrated electron. Two other distinct theoretical models lead to results similar to those of the present QCMD simulations.