DISSOCIATIVE DOUBLE-IONIZATION FOLLOWING VALENCE AND SI-2P CORE-LEVELPHOTOEXCITATION OF SICL4 IN THE RANGE 38-133 EV

The photoionization of SiCl4 has been investigated in the valence and Si:2p inner-shell region using time-of-flight mass spectrometry and sy nchrotron radiation in the range 38-133 eV, Ion yields and branching r atios are reported for charged species arising from the dissociative p hotoionization processes. Various monocations such as Cl+, Cl-2(+), an d SiCln+ (n = 0-4) are observed together with doubly charged species s uch as Si2+, Cl2+, and SiCl2+. The photoion-photoion coincidence (PIPI CO) technique has been employed to investigate a variety of dissociati on processes via Coulomb explosion and to elucidate the dissociation m echanisms. Ion pairs of Si+ + Cl+ and SiCl+ + Cl+ are observed dominan tly in the Si:2p edge. Variation of the ionic fragmentation its a func tion of photon energy is discussed in conjunction with the relevant el ectronic states.