Radiolysis of benzene vapour by low-energy heavy ions

Abstract

Radiolysis of benzene vapour has been studied using 60 keV Ne⁺, Ar⁺, Kr⁺, Xe⁺, and Pb⁺ ion beams from an electromagnetic isotope separator. Radiolytic products have heen investigated both directly by emission spectroscopy and indirectly with e.s.r. spectroscopy and chemical analysis of the deposits formed by condensing the irradiated vapour. H atoms are detected in the gas-phase, C₆H₅ and C₆H₇ in the condensate. No products are detected after dissolution of the condensates. Results from irradiation of C₆H₅D vapour indicate that all H-atoms in the phenyl radical are equivalent with a hyperfine coupling constant of 4.1 G. The ratio between C₆H₅ and C₆H₇ increases with increasing mass of the radiolyzing ion. Relative and absolute cross-sections for production of radicals with the ions mentioned above are compared with theoretical calculations for the reaction C₆H₆+ ion→C₆H₅+ H + ion.