Fragmentation dynamics of CS₂^q+ (q=3-10) molecular ions

Abstract

Dissociative ionization of highly charged CS₂^q+ (q=3-10) molecular ions produced in collisions of CS₂ with Ar⁸⁺ ions is studied at 120 keV energy. Triple coincidence techniques have been applied to measure the velocity components of all three ionic fragments produced in the fragmentation process. The velocity measurements have been used to deduce the total kinetic energy released (KER) in the fragmentation of the molecular ion for each particular product channel. KER values were found to be similar to those predicted by a pure Coulomb explosion model, revealing the apparent unimportance of binding electronic interactions in highly charged, multielectron molecular systems. The propensity of fragmentation into symmetric and asymmetric channels depends only on energetics, with the most exothermic channel being favored. The velocity vectors of the ion fragments yield information on ion structure prior to fragmentation; results indicate that the ionization is impulsive and fragmentation is simultaneous.