ELECTRON-CAPTURE BY SF6 AND SUBSEQUENT DISSOCIATION - A CHEMICAL ACTIVATION MECHANISM

The electron attachment to SF6 and subsequent fragmentation of the SF6 - ion to form SF5- is discussed in terms of a chemical activation mech anism resulting from the formation of the ion with an energy similar t o 1 eV above the thermal energy distribution. Rate constants for elect ron detachment and fragmentation as a function of energy are calculate d using RRKM theory. A suitable choice of rate constants leads to valu es of the SF5-/SF6- ion ratio that are in reasonable agreement with fl owing afterglow experiments carried out at similar to 1 Torr.