OH3- and O2H5- double Rydberg anions: Predictions and comparisons with NH4- and N2H7-

Abstract

A low barrier in the reaction pathway between the double Rydberg isomer of OH3 − and a hydride-water complex indicates that the former species is more difficult to isolate and characterize through anion photoelectron spectroscopy than the well known double Rydberg anion DRA, tetrahedral NH4 − . Electron propagator calculations of vertical electron detachment energies VEDEs and isosurface plots of the electron localization function disclose that the transition state’s electronic structure more closely resembles that of the DRA than that of the hydride-water complex. Possible stabilization of the OH3 − DRA through hydrogen bonding or ion-dipole interactions is examined through calculations on O2H5 − species. Three O2H5 − minima with H− H2O2, hydrogen-bridged, and DRA-molecule structures resemble previously discovered N2H7 − species and have well separated VEDEs that may be observable in anion photoelectron spectra.