Energy relaxation through the π *-state in C, F and O K-shell excited CF 3COCH 3

Abstract

Total photoabsorption spectra of CF 3COCH 3 were measured in the C, F and O K-shell regions and the peak assignments were tentatively given. The K-shell electrons of C, F and O atoms were selectively excited into the π * orbital. The kinetic energy (KE) distribution of CF 3 + formed through the π * states gave the maxima at KE = 0 and 0.43 eV. The yield of CF 3 + with KE = 0 eV increased from 10 to 50% by changing the excitation sites from F 1s to O 1s. This finding was reasonably understood by considering that intramolecular energy flows from the initially excited K-shell electron to vibrational modes of CF 3 group. The KE distribution of CH 3 + showed a mirror image of that for CF 3 +.