Revealing femtosecond multiphoton induced multichannel molecular ionization and fragmentation dynamics by photoelectron–photoion coincidence imaging

Abstract

We report on photoelectron–photoion coincidence imaging after single-color (400 nm) multiphoton excitation of CF 3 I at laser intensities of about 10 12 Watt / cm 2 . The dominant ionic species are the parent CF 3 I + and the CF 3 + fragment from four-photon excitation. Photoelectrons are ejected leaving the parent ion at an internal energy above the dissociation limit leading to fragmentation in CF 3 + + I with low kinetic energy. Weaker dissociation channels of fast CF 3 + + I fragments or fast I + + CF 3 fragments result from the absorption of a fifth photon by the ionized CF 3 I + parent. We propose a new assignment of 7s, 8s intermediate Rydberg levels in CF 3 I resonant at the three-photon level.