Femtosecond Time- and Spectrally Resolved Ion Photofragmentation Spectroscopy: Case Studies of Two Alkylbenzene Cations.

ABSTRACT: Ultrafast photoionization-induced ionic relaxation dynamics in n-propylbenzene and 2,2-dimethylpropylbenzene cations were investigated using time- and spectrally resolved ion photofragmentation spectroscopy with a femtosecond photoionization-photofragmentation (PI-PF) detection scheme. Photoionization was initiated via 1 + 1 REMPI using femtosecond UV pump pulses well below the strong-field ionization regime, and the evolving ionic systems were probed by delayed visible-wavelength probe pulses to induce photofragmentation. Despite substantial ionic fragmentation induced by UV photoionization, the observed parent ion depletion transient signals can be attributed exclusively to the relaxation dynamics of intact parent cations generated at the two-photon level. Highly excited cationic

SUBMITTER: Chu CY 

PROVIDER: S-EPMC12319915 | biostudies-literature | 2025 Jul

REPOSITORIES: biostudies-literature