Field detachment of (H2O)2− clustered with rare gases

Abstract

The electron affinity of (${\mathrm{H}}_2$O${)}_2$ ${\mathrm{}}^{\mathrm{-}}$ is estimated to be 17 meV, based on electric-field-detachment measurements. The shift of the electric field necessary for electron detachment from (${\mathrm{H}}_2$O${)}_2$ ${\mathrm{}}^{\mathrm{-}}$ clustered with Ar, Kr, and Xe is interpreted in terms of Fermi’s theory of the pressure shift of Rydberg spectra, extended to a dipole-bound electron. The implications of these results for electron localization in gaseous and bulk water are briefly discussed.