Double photoionization and dication fragmentation of CF3I: Experiment and theory.

The double photoionization of CF(3)I and the electronic structure and the dissociation dynamics of the CF(3)I(++) dication have been investigated using large ab initio calculations and coincidence techniques. The double photoionization spectrum of CF(3)I consists of a continuous background with a number of narrow bands superimposed. The spectrum is attributed here to the population of groups of close lying electronic states interacting mutually by spin-orbit, spin-spin, and rovibronic couplings. At energies near the vertical double ionization threshold, CF(3) (+)+I(+) ionic fragments are produced. At higher energies, a very specific dissociation with double charge retained on one fragment, CF(3)I(++)-->CF(2)I(++)+F becomes dominant and is attributed to a specific group of dication electronic states.