is of a magnitude such that for each of the electrons the centrifugal force balances the radial force due to the attraction of the nuclei and the repulsion of the other electrons. Denoting this force by
, we get from the condition of the universal constancy of the angular momentum of the electrons, as shown in Part II. [p. 28],
The total energy necessary to remove all the charged particles to infinite distances from each other is equal to the total kinetic energy of the electrons and is given by
For the system in question we have
where
