The electronic structure of molecules by a many-body approach: VI. The assignment of the HeII photoelectron spectrum of SF 6

Abstract

The ionization potentials of SF 6 are studied by an ab initio many-body approach which includes the effects of electron correlation and reorganization beyond the one-particle approximation. The ordering of the ionization potentials in the energy range of the HeII line obtained in the SCF approximation is 1t 1g 5t 1u, 3e g + 1t 2u, 1t 2g, 4t 1u, 5a 1g (the “+” sign denotes nearly equal ionization potentials), whereas in the many-body calculation it is 1t 1g, 5t 1u + 1t 2u, 3e g, 1t 2g, 4t 1u, 5a 1g. The second band in the photoelectron spectrum thus corresponds to two ionization potentials and the third one to only one.