Photodestruction spectra of the anionic water clusters, (H2O)−n, n=18 and 30: Absorption to the red of e−aq

We report absolute photodestruction cross sections of mass selected, anionic water clusters (H2O)−n, n=18 and 30, in order to compare the photoabsorption of the clusters with that of the bulk hydrated electron. The cluster absorptions are similar in magnitude to that of e−aq, but red shifted by about 0.75 eV relative to 298 K e−aq and are observed to rapidly increase in the vicinity of the vertical electron detachment energies of the clusters.