Single-reference electron propagator calculations on vertical ionization energies of ozone

Abstract

Vertical ionization energies of ozone are calculated with electron propagator methods that employ a single reference configuration. Reference determinantal wavefunctions are defined by Hartree–Fock orbitals or by approximate Brueckner orbitals from a coupled-cluster wavefunction. An accurate description of the lowest 2 A 1 , 2 B 2 and 2 A 2 cationic states requires retention of terms in the superoperator Hamiltonian matrix that have been safely neglected in calculations on the ionization energies of typical, closed-shell molecules.