Quantum-chemical Remarks about the Continuum

This interpretation is no conceptual difficulty in the case of the lowest I (by the way, it corresponds to the Einstein threshold of photo-electron emission from metallic surfaces, and to Franck s determination of I of gaseous atoms resulting in the name ionization potential which is now disappearing) but the interesting point is that I of penultimate MO (molecular orbitals) and of inner shells also can be determined. 

However, for chemists, it is fascinating that the penultimate MO also can be detected. It was very difficult previously to connect the eigen-values of an effective one-electron operator in an approximate MO calculation (rarely attain- 

The primary ionization process follows Franck and Condon s principle of unchanged intemuclear distances, like visible and ultra-violet spectra (8). Hence, the centre of gravity (barycentre) of the vibrational structure frequently seen in photo- 

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