Electronic structure of Al3On and Al3On- (n=1-3) clusters

Density functional, quadratic configuration interaction and electron propag ator calculations have yielded structures, isomerization energies, and anio n vertical electron detachment energies pertaining to Al3On- and Al3On, whe re n = 1, 2, or 3. These data suffice for an accurate assignment of recent anion photoelectron spectra. Peaks whose relative intensities vary with exp erimental conditions of ion preparation and transport are associated with i somers whose energies are close to those of the lowest singlet structures. Dyson orbitals associated with the lowest electron detachment energies are dominated by Al-centered functions with antibonding relationships to nearby O centers.