FORMATION OF N3O3- ANION IN (NO)(N)(-) - PHOTOELECTRON-SPECTROSCOPY AND AB-INITIO CALCULATIONS

Photoelectron spectra of (NO)(n)(-) (1 less than or equal to n less th an or equal to 7) were recorded at a photon energy of 4.66 eV, and the vertical detachment energies (VDEs) were determined as a function of the cluster size. The VDE shows an abrupt increase from 2.93 +/- 0.05 eV for n = 2 to 3.70 +/- 0.02 eV for n = 3. This large VDE shift is at tributed to the formation of the N3O3- molecular anion, which acts as a core in the larger clusters; hence, the (NO)(n)(-) clusters with n g reater than or equal to 3 are well described as N3O3-.(NO)(n-3). Ab in itio calculations at the MP2/6-31 + G level predict that the N3O3- mo lecular anion occurs with isomeric forms having either normal or branc hed chain configuration. (C) 1998 Elsevier Science B.V. All rights res erved.