Atoms in Molecules

The molecular structure hypothesis - that a molecule is a collection of atoms linked by a network of bonds - was forged in the crucible of nineteenth century experimental chemistry and has continued to serve as the principal means of ordering and classifying the observations of chemistry. There is a difficulty with the hypothesis, however, in that it is not related directly to the physics which governs the motions of the nuclei and electrons that make up the
atoms and the bonds.