Determination of Bond Dissociation Energies by Electron Impact and Spectroscopic Methods

Some of the excited electronic states are not stable i,e, the interaction between atoms is repulsive at all interatomic distances, and 

To obtain a dissociation energy in this way is a much more complex process than to obtain it from a thermal equilibrium measurement. The amount of information required is much greater, involving as it does a knowledge of the properties of excited or ionized molecules, atoms, and radicals, as well as of normal molecules. 

Although the Franck-Condon principle was first stated for electronic excitation due to the absorption of radiation, it was soon 

The identification of m e for particles In the mass spectrometer is a standard technique discussed in the text-books, but in view of the fact that there is at present much interest in dissociation energies measured by electron impact and relatively little general discussion of the measurements, we shall devote the two follo ving short sections to the discussion of measurement of appearance potential and of kinetic energy, and follow them by examples of the use of the method in Section 5.2.4. 

Molecule Ion Spectroscopic ionization potential V Electron impact result 

---

DETERMINATION OF BOND DISSOCIATION ENERGIES BY ELECTRON IMPACT AND SPECTROSCOPIC METHODS... 

---