Observation of vibronic emission spectrum of jet-cooled 3-chloro-4-fluorobenzyl radical.

We observed the vibronic emission spectrum of 3-chloro-4-fluorobenzyl radical using a corona-excited supersonic jet expansion (CESE) from the precursor 3-chloro-4-fluorotoluene. From an analysis of the observed spectrum, we investigate the formation of the 3-chloro-4-fluorobenzyl and 4-fluorobenzyl radicals and explained the reaction paths with an ab initio study. The D → D transition energy and the frequencies of vibrational mode of the 3-chloro-4-fluorobenzyl radical were determined with a Franck-Condon simulation from density functional theory calculations in the D and D states.