JOURNAL OF CHEMICAL PHYSICS, v.109, no.14, pp.5812 - 5822
Abstract
We report [1+1 ′] picosecond time-resolved pump-probe photoelectron spectra of the UV bands of the allyl radical. The experiments are performed in a molecular beam of allyl radicals, generated by supersonic jet flash pyrolysis. Photoelectron spectroscopy in a magnetic bottle is shown to be a suitable method for investigating the photophysics of organic radicals. Lifetimes were obtained for all vibronic bands between 250 and 238 nm previously assigned by MPI spectroscopy to the electronically excited B 2A 1, C 2B 1, and D 2B 2 states, with values ranging from 20 ps to 9 ps. The nonradiative decay is due to internal conversion to the electronic ground state. Information on the structure of the allyl cation is deduced from the photoelectron spectrum.