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

We report on photoelectron-photoion coincidence imaging after single-color (400 nm) multiphoton excitation of CF3I at laser intensities of about 10(12) Watt/cm(2). The dominant ionic species are the parent CF3I+ and the CF3+ fragment from four-photon excitation. Photoelectrons are ejected leaving the parent ion at an internal energy above the dissociation limit leading to fragmentation in CF3+ + I with low kinetic energy. Weaker dissociation channels of fast CF3+ + I fragments or fast I+ + CF3 fragments result from the absorption of a fifth photon by the ionized CF3I+ parent. We propose a new assignment of 7s, 8s intermediate Rydberg levels in CF3I resonant at the three-photon level. (C) 2009 Elsevier B. V. All rights reserved.