We produced the vibronically excited but jet-cooled 2-fluoro-5-chlorobenzyl radical by corona discharge of precursor 2-fluoro-5-chlorotoluene with a large amount of carrier gas He using a pinhole-type glass nozzle in a technique of corona excited supersonic jet expansion. The vibronic emission spectrum was recorded using a long-path double monochromator in the visible region. From an analysis of the spectrum, we determined the electronic energy of the D-1 -> D-0 transition and vibrational mode frequencies in the ground electronic state of the 2-fluoro-5-chlorobenzyl radical for the first time. In addition, substituent effect on electronic transition energy was discussed for substituents on the benzene ring. (c) 2014 Elsevier B.V. All rights reserved.