Metallic Bond
The attraction between a lattice of metal cations and the delocalised electrons that move freely throughout the structure.
Unit
kJ/mol
In depth
Because the bonding electrons belong to the whole crystal rather than to any pair of atoms, metals conduct heat and electricity, reflect light and deform without shattering — layers of cations can slide past one another while the electron sea keeps holding them together. Strength rises with the number of delocalised electrons per atom.
Examples in the real world
Sodium is soft with one electron per atom; tungsten melts at 3422 °C with six, and is used for lamp filaments.