Photoelectron imaging spectroscopy of molecular and cluster anions: CS2− and OCS−(H2O)1,2

We report the photoelectron imaging study of molecular and cluster anions CS2− and OCS−(H2O)1,2 at 800, 529, and 400 nm, comparing the results for the hydrated OCS− cluster ions to CS2−. The photoelectron angular distributions are interpreted qualitatively using group theory in the framework of the one-electron, electric-dipole approximations. The energetics of OCS−(H2O)1,2 are compared to the theoretical predictions. The vertical detachment energies of OCS−⋅H2O and OCS−(H2O)2 are determined to be 2.07±0.07 and 2.53±0.07 eV, respectively. An indirect estimate of the adiabatic electron affinity of OCS yields a value of −0.04 eV.