Ionic states of S2N2 and assignment of its photoelectron spectrum

Abstract

The valence ionic states of the S₂N₂ molecule are calculated by a many-body Green's function method in the energy range up to 45 eV and the photoelectron spectrum of this molecule is interpreted on the basis of these results. Whereas the molecular-orbital model of ionization can be used to interpret the states below 13 eV, this model is seen to break down at higher energies. Comparison is made with a previous Green's function study and with a recent CI calculation on the low-energy ionic states. A qualitative explanation of the complex band structure in the photoelectron spectrum is attempted based on the bonding properties of the orbitals.