Fragmentation competing with energy relaxation in core-excited CF3CN

Total photoabsorption cross-sections and peak assignments were presented for C(1s) excited CF3CN. It was found that fragmentation of the core-excited CF3CN molecule competes with intramolecular energy redistribution on the basis of two measurements: One is the analysis of the kinetic energies of the CF3+, CF2+, CF+, F+ and CN+ fragment ions in angle-resolved mass spectra observed by using a linear time-of-flight mass spectrometer. This is the first observation that the kinetic energy distribution of fragment ions depends on the site of excitation. The other is site-selective photofragmentation by use of a reflectron type mass spectrometer. These experiments strongly suggest that the CF3 group acts as an effective internal energy reservoir. (C) 2002 Elsevier Science B.V. All rights reserved.