Acetylacetone Photolysis at 280 nm Studied by Velocity-Map Ion Imaging.

ABSTRACT: The photolysis of acetylacetone (AcAc) has been studied using velocity-map ion imaging with pulsed nanosecond lasers. The enolone tautomer of AcAc (CH₃C(O)CH═C(OH)CH₃) was excited in the strong UV absorption band by UV pulses at 280 nm, preparing the S₂(ππ*) state, and products were probed after a short time delay by single-photon VUV ionization at 118.2 nm. Two-color UV + VUV time-of-flight mass spectra show enhancement of fragments at m/z = 15, 42, 43, 58, and 85 at the lowest UV pulse energies and depletion of the parent ion at m/z = 100. Ion images of the five major fragments are all isotropic, indicating dissociation lifetimes that are long on the timescale of molecular rotation but shorter than the laser pulse duration (<6

SUBMITTER: Rinaman JE 

PROVIDER: S-EPMC10440790 | biostudies-literature | 2023 Aug

REPOSITORIES: biostudies-literature