15min:

SEUNG WOON LEE, GI WOO LEE, SANG KUK LEE, Department of Chemistry and the Chemistry Institute of Functional Materials,Pusan National University, Pusan 609-735, Republic of Korea.

We report the first spectroscopic identification of the p -fluoro- -methylbenzyl radical in the gas phase. Precursor p -fluoro-ethylbenzene seeded in a large amount of inert carrier gas helium was electrically discharged to produce the benzyl-type radicals in a corona excited supersonic expansion using a pinhole-type glass nozzle, from which the vibronic emission spectrum was recorded in the visible region using a long path monochromator. From an analysis of the spectrum observed, we found the formation of p -fluoro- -methylbenzyl radical as well as p -fluorobenzyl radical in the jet from the precursor. After eliminating the bands belonging to p -fluorobenzyl radical using the known data, we identified spectroscopically the formation of the p -fluoro- -methylbenzyl radical, in which the energy of the D₁ D₀ electronic transition and a few vibrational mode frequencies in the ground electronic state were determined by comparison with those from an ab initio calculation and with those from the known data of the precursor.