Further evidence for resonant photoelectron-solvent scattering in nitrous oxide cluster anions

The effects of anion solvation by N₂O on photoelectron angular distributions are revisited in light of new photoelectron imaging results for the NO-(N₂O)_n, n = 0-4 cluster anions at 266 nm. The new observations are examined in the context of the previous studies of O- and NO- anions solvated in the gas phase by nitrous oxide [Pichugin; et al. J. Chem. Phys. et al. 2008, 129, 044311.; Velarde; et al. J. Chem. Phys. et al. 2007, 127, 084302.]. The photoelectron angular distributions collected in the three separate studies are summarized and analyzed using bare O- and NO- as zero-solvation references. Solvent-induced deviations of the angular distributions from the zero-solvation reference are scaled by solvation number (n) to yield solvent-induced anisotropy differentials. These differentials, calculated identically for the O-(N₂O)_n and NO-(N ₂O)_n cluster series, show remarkably similar energy dependences, peaking in the vicinity of a known electron-N₂O scattering resonance. The results support the conclusion that the solvation effect on the photoelectron angular distributions in these cases is primarily due to resonant interaction of photoelectrons with the N₂O solvent, rather than a solvent-induced perturbation of the parent-anion electronic wave function.