Electron stimulated desorption of excited OH radicals from SrF₂ surfaces

Electron stimulated desorption (ESD) of OH radicals from H2O adsorbed on SrF2 surfaces was investigated in order to determine the energy distribution of desorbed excited radicals. Kinetic energies were determined by measuring the spatial extent of the fluorescence above the surface and vibrational and rotational energies were determined by analysing the intensity distribution of the rovibrational spectra. Comparable kinetic and vibrational energies were found (Etr = 0.2 eV, Evib = 0.17 eV), where the rotational energy was measured to be much smaller (Erot = 0.04 eV). These results are discussed in terms of possible dissociation channels of the adsorbed molecule. © 1986.