Fragment appearance energies in dissociative ionization of a sulfur hexafluoride molecule by electron impact

Theoretical analysis of the fragment appearance energies corresponding to possible channels of formation of SFk+ fragments in dissociative ionization of the SF6 molecule by an electron impact is carried out. The total energies of neutral and ion molecular and atomic fragments are calculated using the theoretical methods of the GAMESS program complex. It is concluded that apart from dissociative ionization via autoionizing repulsive electronic states of the SF6 molecule, the excitation channels for SFk+ fragments and F2 molecules play a significant role, which leads to higher values of the observed fragment appearance energy as compared to theoretical values. The dependence of the energy corresponding to the formation of SFk+ c fragments on the number k of fluorine atoms is considered.