title: Excited-state decay of hydrocarbon radicals, investigated by femtosecond time-resolved photoionization: ethyl, propargyl, and benzyl.
abstract: The excited state decay of the hydrocarbon radicals ethyl, C(2)H(5); propargyl, C(3)H(3); and benzyl, C(7)H(7) was investigated by femtosecond time-resolved photoionization. Radicals were generated by flash pyrolysis of n-propyl nitrite, propargyl bromide, and toluene, respectively. It is shown that the 2 (2)A(') (3s) Rydberg state of ethyl excited at 250 nm decays with a time constant of 20 fs. No residual signal was observed at longer delay times. For the 3 (2)B(1) state of propargyl excited at 255 nm a slower decay with a time constant 50+/-10 fs was determined. The 4 (2)B(2) state of benzyl excited at 255 nm decays within 150+/-30 fs.
authors.affiliation: Institute of Physical Chemistry, University of Würzburg, Am Hubland, D-97074 Würzburg, Germany.
authors.forename: Matthias
authors.initials: M
authors.lastname: Zierhut
authors.forename: Bastian
authors.initials: B
authors.lastname: Noller
authors.forename: Thomas
authors.initials: T
authors.lastname: Schultz
authors.forename: Ingo
authors.initials: I
authors.lastname: Fischer