Photodetachment of electrons from large molecular systems: Benzyl anion. An upper limit to the electron affinity of C6H5CH2

The relative cross section for the gas phase photodetachment of electrons has been determined for the benzyl anion in the wavelength region 870–1330 nm (1.43–0.93 eV). An ion cyclotron resonance spectrometer was used to generate, trap, and detect the negative ions and a 1000 W xenon arc lamp with a grating monochromator was employed as the light source. An upper limit to the electron affinity of the benzyl radical was determined to be 0.88±0.06 eV (20.4±1.5 kcal/mole).