Collision-Induced Decomposition of Multiatomic Ions

Abstract

The dependence upon ion mass of the loss of translational energy suffered by an ion with kiloelectron volt energy as a result of collision with helium has been investigated over the mass range 400 u to 1600 u. At masses below about 1500 u and an incident ion energy of 8 keV, there is forward-scattering in the centre-of-mass frame: at mass 1620 u at the same energy, there is backscattering in the centre-of-mass frame. The uptake of internal energy by an ion is at a maximum in the region in which the change from forward-scattering to back-scattering occurs.