On the constitution of atoms and molecules

by Niels Bohr

.)

For a configuration of a helium nucleus and three electrons, we get

Since

for this configuration is smaller than for the configuration

, the theory indicates that a helium atom cannot acquire a negative charge. This is in agreement with experimental evidence, which shows that helium atoms have no “affinity” for free electrons[33].

In a later paper it will be shown that the theory offers a simple explanation of the marked difference in the tendency of hydrogen and helium atoms to combine into molecules.