A triple bond consists of three shared electron pairs, forming one sigma and two pi bonds.

There are no shared electron pairs to repel each other, the ions should simply be packed as efficiently as possible.

Boranes are electron-deficient and pose a problem for conventional descriptions of covalent bonding that involves shared electron pairs.

Lewis did not publish his theory of the cubic atom, but in 1916 it became an important part of his theory of the shared electron pair bond.

While the idea of shared electron pairs provides an effective qualitative picture of covalent bonding, quantum mechanics is needed to understand the nature of these bonds and predict the structures and properties of simple molecules.