RADICAL INTERMEDIATES IN THE PHOTOINDUCED FORMATION OF BENZENE CATION-RADICALS OVER H-ZSM-5 ZEOLITES

Radical particles are shown to appear under irradiation (hv greater th an or equal to 2.8 eV) of H-ZSM-5 zeolites with adsorbed benzene. The particles appeared to be benzene cation-radical precursors over the ze olite. Heating resulted in irreversible destruction of the particles a nd emergence of a benzene cation-radical spectrum. The obtained radica ls have no detectable hyperfine splittings on the protons, their spect rum remaining almost the same when deuterobenzene was used. The possib le structure of the particles is discussed.