Electron-Impact Spectroscopy of Molecules

摘要: Electrons and ions have been used for the excitation of matter ever since Franck-Hertz experiment in 1914 (see [1]). Although it is not useful to speak beam experiments those early years, soon became obvious that use a monochromatic electron or ion would open up new avenues experimental theoretical advancement. In 1925, Goudsmit Uhlenbeck [2] discovered spin were thereby able explain multiplet structures their spectra. (This especially important low-energy electron-impact experiments, where also determines transition probabilities.) A third development, Bethe theory (1930), must be mentioned: This provided basis analysis interaction between high-energy electrons [3]. The initial formalism explaining results was now complete; operational when, after World War II, technical improvements allowed study single-particle collision processes. Better vacuum systems, optics solid-state electronics permitted an enormous increase results. These concerned only beams gas-phase spectroscopic research but many other applications as well.