ELECTRON-BINDING ENERGIES OF LINEAR C-3, C-5, C-7, AND C-9 CLUSTERS

Electron propagator calculations are performed on the vertical ionization energies and electron affinities of linear C-3, C-5, C-7, and C-9 clusters with a variety of correlation approximations and basis sets. Estimates of adiabatic electron affinities are made as well, and are in excellent agreement with experiment. A bound, excited state of C-9(-) has been found. Correlation effects are large for the electron affinity calculations and for many vertical ionization energies. The Koopmans description of final states is valid for the Feynman-Dyson amplitudes, but for many cationic states there is considerable shakeup character.