, mentioned in the former section. As we have seen, the necessary condition for the formation of a configuration of this kind is that one of the atoms in the molecule is able to bind three electrons in the outer ring. According to the theory, this condition is not satisfied for a hydrogen or a helium atom, but is for an oxygen atom. With the symbols used in [Part II.] the configuration suggested for the oxygen atom was given by
. From a calculation, as that indicated in [Part II.], we get for this configuration
, while for the configuration
we get
. Since the latter value for
