GENERATION AND IR SPECTROSCOPIC STUDY OF BENZYL RADICAL

The benzyl radical C6H5CH2 has been obtained by gas phase pyrolysis of two different precursors, benzyl bromide and dibenzyl, and studied in an argon matrix at 12 K by IR spectroscopy. Similarly, the deuterosubstituted benzyl radicals, C6H5CD2 and C6D5CH2, have been investigated. The assignment of the IR bands of the benzyl radical and its deuteroanalogs to fundamental modes and a calculation of the valence force field have been performed. The obtained data give evidence of sp2 hybridization of the methylene carbon atom and delocalization of the electron density between the ring and the CH2 group, and are in good agreement with the planar structure of the radical.