Journal of Physical Chemistry A, Vol.117, No.39, 9331-9342, 2013
Photoionization Cross Section of the Propargyl Radical and Some General Ideas for Estimating Radical Cross Sections
A combination of velocity map ion imaging, mass spectrometry, and a laser-based vacuum ultraviolet light source was used to perform a new measurement of the absolute photoionization cross section of the propargyl radical. The measurements are in good agreement with the recent determination of Savee et al. [J. Chem. Phys. 2012, 136, 134307], and significantly larger than an earlier determination. The results are discussed and rationalized in terms of some general ideas about absolute photoionization cross sections. The potential utility of these ideas is illustrated by using recent cross section measurements for a number of molecular radicals, including methyl, allyl and 2-propenyl, phenyl, and vinyl.