Optical Radiation from Electron Sputtering of Alkali Halides
Electron-surface collisions have been observed to result in the emission of optical radiation from excited atoms and molecules desorbed from alkali halide single crystal surfaces. The detected radiation included Na and Li resonance lines, hydrogen Balmer emission, and OH molecular radiation. Much previous experimental and theoretical effort has been devoted to electron stimulated desorption (ESD) of ground state neutrals and ions , and in particular from alkali halides [2,3,4]. The few studies concerned with excited particles have dealt primarily with ejected metastable neutrals . In one case involving electron bombardment fluorescence of ice, a tentative identification has been made of OH molecular radiation . The results reported here include a) the first definitive work on optical radiation from electron bombardment induced emission of excited free substrate particles , and b) the first observations of characteristic radiation from previously adsorbed free atoms and molecules.
KeywordsOptical Radiation Alkali Halide Photon Spectrum Single Crystal Surface Electron Bombardment
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