Anion solvation at the microscopic level: Photoelectron spectroscopy of the solvated anion clusters, NO−(Y)n, where Y=Ar, Kr, Xe, N2O, H2S, NH3, H2O, and C2H4(OH)2

The negative ion photoelectron spectra of the gas-phase, ion-neutral complexes; NO−(Ar)n=1–14, NO−(Kr)1, NO−(Xe)n=1–4, NO−(N2O)n=3–5, NO−(H2S)1, NO−(NH3)1, and NO−(EG)1 [EG=ethylene glycol] are reported herein, building on our previous photoelectron studies of NO−(N2O)1,2 and NO−(H2O)1,2. Anion solvation energetic and structural implications are explored as a function of cluster size in several of these and as a result of varying the nature of the solvent in others. Analysis of these spectra yields adiabatic electron affinities, total stabilization (solvation) energies, and stepwise stabilization (solvation) energies for each of the species studied. An examination of NO−(Ar)n=1–14 energetics as a function of cluster size reveals that its first solvation shell closes at n=12, with an icosahedral structure there strongly implied. This result is analogous to that previously found in our study of O−(Ar)n. Inspection of stepwise stabilization energy size dependencies, however, suggests drastically different st...